Characteristics of Primary Papillary Thyroid Carcinoma with False-Negative Findings on Initial 18F-FDG PET/CT

Background

We often observe that uptake of tracer is not detected in the primary cancer focus in patients with histologically proven papillary thyroid carcinoma (PTC) on preoperative ¹⁸F-fluorodeoxyglucose positron emission tomography-computed tomography (¹⁸F-FDG PET/CT). Therefore, we analyzed the clinical and pathologic variables affecting false-negative findings in primary tumors on preoperative ¹⁸F-FDG PET/CT.

Methods

We retrospectively reviewed the medical records of 115 consecutive patients who underwent ¹⁸F-FDG PET/CT for initial evaluation and were diagnosed with PTC by postoperative permanent biopsy. The clinical and pathologic characteristics that influence the ¹⁸F-FDG PET/CT findings in these patients were analyzed with respect to the following variables: age, gender, tumor size, multifocality of the primary tumor, perithyroidal invasion, lymphovascular or capsular invasion, and central lymph node metastasis-based final pathology.

Results

Twenty-six (22.6%) patients had false-negative ¹⁸F-FDG PET/CT findings. In patients with negative ¹⁸F-FDG PET/CT findings, tumor size, and perithyroidal and lymphovascular invasion were significantly less than in patients with positive ¹⁸F-FDG PET/CT findings. Tumors >1 cm in size were correlated with ¹⁸F-FDG PET/CT positivity. On multivariate analysis, perithyroidal invasion (P = 0.026, odds ratio = 7.714) and lymphovascular invasion (P = 0.036, odds ratio = 3.500) were independent factors for ¹⁸F-FDG PET/CT positivity. However, there were no significant differences between ¹⁸F-FDG PET/CT positivity and age, gender, capsular invasion, and central lymph node metastasis based on final pathology.

Conclusions

Tumor size and perithyroidal and lymphovascular invasion of papillary carcinoma can influence ¹⁸F-FDG PET/CT findings. Absence of perithyroidal and lymphovascular invasion were independent variables for false-negative findings on initial ¹⁸F-FDG PET/CT in patients with PTC.     

18F-FAMT-PET Is Useful for the Diagnosis of Lymph Node Metastasis in Operable Esophageal Squamous Cell Carcinoma

Background

The role and potential usefulness of positron emission tomography (PET) scanning in certain tumors has been widely investigated in recent years. ¹⁸F-FAMT (L-[3-¹⁸F]-α-methyltyrosine) is an amino acid tracer for PET. This study investigated whether PET/CT with ¹⁸F-FAMT provides additional information for preoperative diagnostic workup of esophageal squamous cell carcinoma compared with that obtained by ¹⁸F-FDG (fluorodeoxyglucose) PET or CT.

Methods

PET/CT studies with ¹⁸F-FAMT and ¹⁸F-FDG were performed as a part of the preoperative workup in 21 patients with histologically confirmed esophageal squamous cell carcinoma.

Results

For the detection of primary esophageal cancer, ¹⁸F-FAMT-PET exhibited a sensitivity of 76.2%, whereas the sensitivity for ¹⁸F-FDG-PET was 90.5% (P = 0.214). ¹⁸F-FAMT uptake in primary tumors showed significant correlation with depth of invasion (P = 0.005), lymph node metastasis (P = 0.045), stage (P = 0.031), and lymphatic invasion (P = 0.029). In the evaluation of individual lymph node groups, ¹⁸F-FAMT-PET exhibited 18.2% sensitivity, 100% specificity, 71.9% accuracy, 100% positive predictive value, and 70.0% negative predictive value, compared with 24.2%, 93.7%, 69.8%, 66.6%, and 70.2%, respectively, for ¹⁸F FDG-PET. CT exhibited 39.4% sensitivity, 85.7% specificity, 69.8% accuracy, 59.1% positive predictive value, and 73.0% negative predictive value. The specificity of ¹⁸F-FAMT-PET is significantly higher than that of ¹⁸F-FDG-PET (P = 0.042) and CT (P = 0.002). ¹⁸F-FAMT-PET did not have any false-positive findings compared to those with ¹⁸F-FDG-PET.

Conclusions

Our findings suggest that the addition of ¹⁸F-FAMT-PET to ¹⁸F-FDG-PET and CT would permit more precise staging of esophageal cancer.     

18F-FDG Uptake at Initial Staging of the Adrenocortical Cancers: A Diagnostic Tool but Not of Prognostic Value

Background

Adrenocortical carcinoma (ACC) is a rare cancer for which little level evidence exists to guide management. ¹⁸F-FDG PET (¹⁸F-fluorodeoxyglucose positron emission tomography) is an increasingly used diagnostic tool in patients with suspicious or indeterminate adrenal tumors. In some other solid tumors, ¹⁸F-FDG PET may offer prognostic information that can guide optimal patient treatment. The aim of the present study was to evaluate whether preoperative ¹⁸F-FDG PET based on SUVs assessments has a prognostic value in ACC patients.

Methods

A retrospective analysis was performed in patients who underwent ¹⁸F-FDG PET/CT for the evaluation of ACC. Inclusion criteria were an unequivocal diagnosis of ACC; all data from primary diagnosis available; ¹⁸F-FDG PET/CT performed prior to surgery or other treatment of the primary tumor; a minimum of 6-months follow-up for surviving patients. All ¹⁸F-FDG PET/CT procedures were reinterpreted in a blind fashion.

Results

Thirty-seven patients (23 without metastasis [M0], 14 with metastasis [M1]) fulfilled the study criteria. Median uptake values were tumor standardized uptake values (SUV)_max = 11 (range: 3–56) and a tumor/liver SUV_max ratio = 4.2 (range: 1.3–15). Median follow-up was 20 months. Although classic risk factors (tumoral stage, Weiss score) were associated with poor outcome, there was no correlation between primary tumor FDG uptake with overall survival (OS) and disease free survival (DFS) in M0 patients and with overall survival in M1 patients. ¹⁸F-FDG uptake correlated inconsistently with sinister histological features, such as atypical mitoses or necrosis.

Conclusions

At initial staging, primary tumor FDG uptake in ACC patients does not correlate with OS and DFS at 2 years. Patient prognosis and treatment strategy should not be based on uptake values.     

Early Assessment of Axillary Response with 18F-FDG PET/CT during Neoadjuvant Chemotherapy in Stage II–III Breast Cancer: Implications for Surgical Management of the Axilla

Background

If all initially node-positive patients undergo axillary lymph node dissection (ALND) after neoadjuvant chemotherapy (NAC), overtreatment may occur in patients with complete response. Positron emission tomography–computed tomography (PET/CT) during NAC may predict axillary response and select patients appropriate for less invasive treatment after NAC. We evaluated the value of sequential ¹⁸F fluorodeoxyglucose (FDG) PET/CTs during NAC for axillary response monitoring in stage II–III breast cancer.

Methods

A total of 219 PET/CTs were performed in 80 patients with cytology-proven, node-positive disease at baseline (PET/CT1, n = 80) and twice during NAC (PET/CT2 n = 62, PET/CT3, n = 77). The relative changes in maximum standardized uptake value (SUV_max) of axillary nodes were examined for their ability to assess pathological response. All patients underwent ALND after chemotherapy, and complete axillary response (pCR), defined as absence of isolated tumor cells and of micro- and macrometastases, served as the reference standard.

Results

A total of 32 (40 %) patients experienced axillary pCR. The relative decrease in SUV_max was significantly higher in patients with pCR than in those without, both on PET/CT2 (p < 0.001) and PET/CT3 (p = 0.025). The area under the receiver operating characteristic curve values for PET/CT2 and PET/CT3 were 0.80 (95 % confidence interval 0.68–0.92) and 0.65 (95 % confidence interval 0.52–0.79), respectively. A relative decrease of ≥60 % on PET/CT2 had an excellent specificity (35 of 37, 95 %), a high positive predictive value (12 of 14, 86 %), and a sensitivity of 48 %—that is, it accurately identified histologic pCR in 12 of 25 patients with disease that responded to therapy.

Conclusions

¹⁸F-FDG PET/CT early during NAC is useful for axillary response monitoring in cytology-proven node-positive breast cancer because it identifies pathological response, thus permitting ALND to be spared.     

18F-FDG-PET/CT to Select Patients with Peritoneal Carcinomatosis for Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

Background

Cytoreductive surgery followed by hyperthermic intraperitoneal chemotherapy (HIPEC) is associated with significantly longer survival in patients with peritoneal carcinomatosis (PC). So far, no morphological imaging method has proven to accurately assess the intra-abdominal tumor spread. This study was designed to predict tumor load in patients with PC using dual-modality ¹⁸FDG-PET/CT and to compare the results with those of PET and CT alone by correlating imaging findings with intraoperative staging.

Methods

Twenty-two patients with PC from gastrointestinal (n = 13), ovarian cancer (n = 8), and mesothelioma (n = 1) underwent contrast-enhanced ¹⁸FDG-PET/CT before surgery and HIPEC. In a retrospective analysis PET, CT, and fused PET/CT were separately and blindly reviewed for the extent of peritoneal involvement using the Peritoneal Cancer Index (PCI). Imaging results were correlated with the intraoperative PCI using Pearson’s correlation coefficient and linear regression analysis.

Results

There was a strong correlation between the PCI obtained with PET/CT and the surgical PCI with respect to the total score (r = 0.951) as well as in the regional analysis (small bowel, r = 0.838; other, r = 0.703). The correlation was slightly lower for CT alone (total score, r = 0.919; small bowel, r = 0.754; other, r = 0.666) and significantly lower (p = 0.002) for PET alone (total score, r = 0.793; small bowel, r = 0.553, other, 0.507).

Conclusions

Contrast-enhanced CT is superior compared with PET alone to predict the extent of PC. In our patient group, the combination of both modalities (contrast enhanced PET/CT) yielded the best results and proved to be a useful tool for selecting candidates for peritonectomy and HIPEC.     

Metabolic Response to Preoperative Chemotherapy Predicts Prognosis for Patients Undergoing Surgical Resection of Colorectal Cancer Metastatic to the Liver

Background

Biological characteristics of colorectal cancer liver metastases (CRCLM) are increasingly recognized as major determinants of patient outcome. The purpose of this study was to evaluate the prognostic value of metabolic response to preoperative chemotherapy as quantified by ¹⁸F-FDG positron emission tomography (PET) for patients undergoing liver resection of CRCLM.

Methods

All patients (n = 80) who had staging PET before liver resection for CRCLM at Austin Health in Melbourne between 2004 and 2011 were included. Thirty-seven patients had PET and CT imaging before and after preoperative chemotherapy. Semiquantitative PET parameters—maximum standardized uptake variable (SUV_max), metabolic tumour volume (MTV), and total glycolytic volume (TGV)—were derived. Metabolic response was determined by the proportional change in PET parameters (?SUV_max, ?MTV, ?TGV). Prognostic scores, CT RECIST response, and tumour regression grading (TRG) were also assessed. Correlation to recurrence-free (RFS) and overall survival (OS) was assessed using Kaplan–Meier survival and multivariate analysis.

Results

Semiquantitative parameters on staging PET before chemotherapy were not predictive of prognosis, whereas all parameters after chemotherapy were prognostic for RFS and OS. Only ?SUV_max was predictive of RFS and OS on multivariate analysis. Patients with metabolically responsive tumours had an OS of 86 % at 3 years vs. 38 % with nonresponsive or progressive tumours (p = 0.003). RECIST and TRG did not predict outcome.

Conclusions

Tumour metabolic response to preoperative chemotherapy as quantified by PET is predictive of prognosis in patients undergoing resection of CRCLM. Assessing metabolic response uniquely characterizes tumour biology, which may allow future optimization of patient and treatment selection.     

Acute exacerbation of interstitial lung disease with lung cancer after surgery: evaluation with 2-[18]-fluoro-2-deoxy-d-glucose positron emission tomography

Purpose

Interstitial lung disease (ILD) has been associated with primary lung cancer and an increased risk of postoperative acute exacerbation (AE). The effectiveness of 2-[18]-fluoro-2-deoxy-d-glucose (¹⁸F-FDG) positron emission tomography (PET) for staging lung cancer is well established. This study investigates the association of FDG uptake on PET in patients with AE of ILD.

Methods

The subjects of this retrospective study were 1309 patients with lung cancer, who underwent pulmonary resection at Shizuoka Cancer Center between September, 2002 and January, 2011. ILD was diagnosed with chest computed tomography in 95 patients, 81 of whom underwent ¹⁸F-FDG PET before surgery. Six patients suffered from AE after surgery (AE group), while the remaining 75 (non-AE group) did not. We investigated the clinico-pathological findings and the results of FDG uptake on PET using the value of the I/M ratio, which is the ratio of the peak of standardized uptake value (SUV) of the ILD area to the mean SUV of the mediastinum.

Results

There was no significant difference in clinico-pathological findings, but a significance difference in the I/M ratio (P = 0.0102).

Conclusion

The FDG uptake in PET may be a predictive factor for AE of ILD in patients who have undergone lung cancer surgery.     

Diagnostic value of 18F-FDG PET/CT for lymph node metastasis of esophageal squamous cell carcinoma

Purpose

This study investigated the diagnostic accuracy of hybrid positron-emission tomography/computed tomography (PET/CT) for lymph node (LN) metastasis of esophageal cancer. We also investigated the correlation between the size of metastatic nests and the detection by PET/CT.

Methods

Two hundred and fifty-eight patients with esophageal squamous cell carcinoma who underwent esophagectomy with two- or three-field radical lymphadenectomy were analyzed retrospectively. We compared the diagnosis of preoperative PET/CT to the postoperative histopathological examination by each anatomical field (n = 1,231) in all 258 patients. The metastatic LNs resected from PET/CT positive fields were classified as belonging to the PET/CT-N-positive group (n = 229) and those from negative fields as belonging to the PET/CT-N-negative group (n = 352). The cross-sectional areas of metastatic nests were measured in each metastatic LN.

Results

Of the 1,231 fields, 275 (22 %) were positive for metastasis, including 581 LNs from 408 regional LN stations. The sensitivity and specificity of PET/CT examined by each anatomical field were 25.8 and 97.8 %, respectively. The median area of metastatic nests was 17.7 mm² in the PET/CT-N-positive group, and 7.7 mm² in the PET/CT-N-negative group (p < 0.001).

Conclusions

A significant correlation was suggested between the nest size and detection by PET/CT. Because of its low sensitivity, PET/CT alone is insufficient to determine the surgical procedures, especially when considering reduction surgery.     

Preoperative Consolidation-to-Tumor Ratio and SUVmax Stratify the Risk of Recurrence in Patients Undergoing Limited Resection for Lung Adenocarcinoma ≤2 cm

Purpose

Limited resection is an increasingly utilized option for treatment of clinical stage IA lung adenocarcinoma (ADC) ≤2 cm (T1aN0M0), yet there are no validated predictive factors for postoperative recurrence. We investigated the prognostic value of preoperative consolidation/tumor (C/T) ratio [on computed tomography (CT) scan] and maximum standardized uptake value (SUVmax) on ¹⁸F-fluorodeoxyglucose-positron emission tomography (PET) scan.

Methods

We retrospectively reviewed 962 consecutive patients who underwent limited resection for lung cancer at Memorial Sloan-Kettering between 2000 and 2008. Patients with available CT and PET scans were included in the analysis. C/T ratio of 25 % (in accordance with the Japan Clinical Oncology Group 0201) and SUVmax of 2.2 (cohort median) were used as cutoffs. Cumulative incidence of recurrence (CIR) was assessed.

Results

A total of 181 patients met the study inclusion criteria. Patients with a low C/T ratio (n = 15) had a significantly lower 5-year recurrence rate compared with patients with a high C/T ratio (n = 166) (5-year CIR, 0 vs. 33 %; p = 0.015), as did patients with low SUVmax (n = 86) compared with patients with high SUVmax (n = 95; 5-year CIR, 18 vs. 40 %; p = 0.002). Furthermore, within the high C/T ratio group, SUVmax further stratified risk of recurrence [5-year CIR, 22 % (low) vs. 40 % (high); p = 0.018].

Conclusions

With the expected increase in diagnoses of small lung ADC as a result of more widespread use of CT screening, C/T ratio and SUVmax are widely available markers that can be used to stratify the risk of recurrence among cT1aN0M0 patients after limited resection.     

18-Fluorodeoxyglucose Positron Emission Tomography Predicts Recurrence in Resected Pancreatic Ductal Adenocarcinoma

Background

We aimed to determine whether treatment should be stratified according to 18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) maximum standardized uptake values (SUV_max) in pancreatic ductal adenocarcinoma.

Methods

Patients who underwent preoperative 18F-FDG PET/CT between 2006 and 2014 (n = 138) were stratified into high (≥ 4.85) and low (< 4.85) PET groups. The clinicopathological characteristics and prognostic outcomes were analyzed retrospectively.

Results

The primary tumor SUV_max was positively correlated with preoperative CA19-9 levels (P < 0.001). The high PET group failed to achieve postoperative CA19-9 normalization (P = 0.014). Disease-specific (P < 0.001), recurrence-free (P < 0.001), liver recurrence-free (P < 0.001), and peritoneal recurrence-free (P = 0.020) survivals were significantly shorter in the high PET group. The primary tumor SUV_max was an independent predictive risk factor for liver metastasis (hazard ratio 3.46, 95% confidence interval 1.61–7.87; P = 0.001) and peritoneal recurrence (hazard ratio 3.36, 95% confidence interval 1.18–10.89; P = 0.023).

Conclusions

Surgical resection failed to achieve CA19-9 normalization in the high PET group and distant recurrence was frequent. This suggests the potential for residual cancer at distant sites, even after curative resection. Stronger preoperative systemic chemotherapy is preferred for the high PET group patients.

     

Outcome Analyses of Unusual Site Neck Recurrence in Oral Cavity Cancer

Aim

To understand the frequency, clinical significance, and benefits of salvage therapy in oral cavity squamous cell carcinoma (OSCC) patients with regional nodal recurrence at unusual sites (prelaryngeal area, parotid area, and retropharyngeal area).

Methods

We examined 178 patients with neck recurrence at levels I–V (usual group) and 26 patients outside levels I–V (unusual group). The 5-year survival rates served as the main outcome measure.

Results

Of the 26 unusual group patients, the neck recurrence sites were as follows: 5 at the prelaryngeal area, 13 at the parotid area, and 8 at the retropharyngeal area. Multivariate analyses demonstrated that poor differentiation, pN2, extracapsular spread (ECS), tumor depth ≥10 mm, relapse time ≤10 months, local recurrence, neck recurrence at unusual sites, and distant metastases were independent prognostic factors for 5-year disease-specific survival (DSS), whereas pN2, ECS, tumor depth ≥10 mm, relapse time ≤10 months, neck recurrence at unusual sites, and distant metastases were independent prognostic factors for 5-year overall survival (OS). The 6-month and 18-month survival rates after the N-relapse date for the salvaged-usual group, the salvaged-unusual group, and the nonsalvaged patients were 73 %/46 %, 40 %/0 %, and 10 %/0 % (P < 0.0001), respectively [DSS: salvaged-unusual group (hazard ratio/95 % confidence interval), 2.060/1.058–4.008, P = 0.033; salvaged-usual group, 6.420/4.340–9.496, P < 0.001; OS: salvaged-unusual group, 2.100/1.080–4.081, P = 0.029; salvaged-usual group, 6.514/4.418–9.606, P < 0.001].

Conclusions

Our findings demonstrate that OSCC patients with regional nodal recurrence at unusual sites had poor outcomes.     

BRAF V600E Mutation Independently Predicts Central Compartment Lymph Node Metastasis in Patients with Papillary Thyroid Cancer

Purpose

This study was designed to examine whether available preoperative clinical parameters, including B-type Raf kinase (BRAF) V600E mutation status, can identify patients at risk for central compartment lymph node metastasis (CLNM).

Methods

Under an institutional review board-approved protocol, we conducted a single-center, retrospective review of all patients who had initial thyroidectomy for histologic papillary thyroid carcinoma (PTC) during 2010. The presence of CLNM was examined for correlation with available preoperative clinical parameters, including tumor size, gender, age, and BRAF mutation status.

Results

Cervical lymph node resection and molecular testing on FNAB or histopathologic specimen was performed on a consecutive series of 156 study patients with histologic PTC. Overall, CLNM was diagnosed in 37 % and 46 % were BRAF-mutation-positive. BRAF positivity was the only clinical parameter associated with CLNM (BRAF, p = 0.002; tumor size ≥2 cm, p = 0.16; male gender, p = 0.1; age ≥45 years, p = 0.3) and remained an independent predictor of CLNM on multiple logistic regression analysis (odds ratio (OR) 3.2, p = 0.001). The PPV and NPV of BRAF positivity for CLNM was 50 and 74 %, respectively. When restricting the analysis to the subset of 38 patients who had molecular testing performed preoperatively on FNAB, the PPV and NPV of BRAF positivity for CLNM was 47 and 91 %, respectively, and BRAF positivity was still a significant predictor of CLNM on both univariate (OR 8.4, p = 0.01) and multivariate (OR 9.7, p = 0.02) analyses.

Conclusions

Of the commonly used clinical parameters available preoperatively, the BRAF V600E mutation is the only independent predictor of CLNM in PTC and can be utilized to guide the extent of initial surgery.     

Effects of obesity on the outcome of laparoscopic surgery for colorectal cancer

Purpose

This study evaluated the feasibility and safety of laparoscopic colorectal surgery for cancer in obese patients based on the short-term outcomes.

Methods

We conducted a retrospective analysis of 561 patients with colorectal cancer treated from April 2007 to October 2010. The surgical outcomes were compared between non-obese (BMI <25 kg/m²) and obese (BMI ≥25 kg/m²) patients.

Results

All of the enrolled patients were classified as non-obese (n = 421) or obese (n = 140). The obese group had a significantly higher proportion of male patients (72.1 vs. 57.0 %; P = 0.002), a higher incidence of left colon cancer (49.3 vs. 36.8 %; P = 0.033), and more systematic comorbidities (P < 0.001) than did the non-obese group. The length of the surgery was significantly longer in obese than in non-obese patients (221 vs. 207 min; P = 0.025). There was no significant difference in the overall incidence of postoperative complications between the two groups; however, surgical wound infections were more common in obese patients (12.1 vs. 5.2 %; P = 0.005). Obesity was not a significant-independent risk factor for total postoperative complications (odds ratio 1.330; P = 0.289).

Conclusion

Laparoscopic colorectal surgery is technically feasible and safe for obese patients and provides all the benefits of a minimally invasive approach.     

The Impact of Preoperative Lymph Node Size on Long-Term Outcome Following Curative Gastrectomy for Gastric Cancer

Background

Multidetector-row computed tomography (MDCT) is widely used to predict pathological nodal status. However, an appropriate nodal size cutoff value to predict pathological nodal status has not been determined, and the impact of preoperative lymph node size on long-term outcomes is unclear.

Methods

This study included 137 gastric cancer patients with nodal involvement who underwent R0 gastrectomy between September 2002 and December 2006. Lymph nodes with a short-axis diameter of 10 mm or more as measured by MDCT were regarded as metastasized. An appropriate cutoff value with a high positive predictive value (PPV) and high specificity also was identified, and the subsequent clinicopathological characteristics and long-term outcomes were investigated.

Results

A cutoff value of 15 mm was found to be appropriate for grouping patients into large (≥15 mm) and small (<15 mm) lymph node metastasis (LLNM and SLNM) groups, with a high PPV (98.6 %) and specificity (99.8 %). There were no differences in clinicopathological characteristics between the groups except for pathological nodal status. In the LLNM group, the 5-year survival rate was 55 %, which was significantly lower than in the SLNM group (73.2 %; P = 0.008). After stratification by tumor depth, the same trend was observed in patients with pT3 disease (46.8 % vs. 72.7 %; P = 0.015) and those with pT4 disease (14.3 % vs. 64.8 %; P = 0.035).

Conclusions

Gastric cancer patients with lymph nodes measuring 15 mm or more preoperatively have worse long-term outcomes. These patients would therefore be suitable candidates for future clinical trials investigating the efficacy of neoadjuvant chemotherapies.     

Evaluation of the Nodal Status in the 7th Edition of the UICC-TNM Classification for Esophageal Squamous Cell Carcinoma: Proposed Modifications for Improved Survival Stratification

Background

The 7th edition of the Union for International Cancer Control-TNM (UICC-TNM) classification for esophageal carcinoma made considerable modifications to the definition of N-staging by the number of involved lymph nodes and the regional node boundary. There were few validations of the regional boundary. We evaluated the nodal status of this classification for esophageal squamous cell carcinoma (ESCC).

Methods

There were 665 patients reviewed who had ESCC and underwent esophagectomy between 1997 and 2012. We evaluated the impact of the location of lymph node metastasis on overall survival.

Results

There were 414 patients (61.7 %) who had lymph node metastases. The overall 5-year survival rate was 54.7 %. There were no significant differences in survival among N2, N3, and M1 patients. Cox regression analysis revealed that common hepatic or splenic node involvements (P = 0.001), pT stage (P = 0.0002), and pN stage (P < 0.0001) were independent predictors of survival, but supraclavicular node involvement (P = 0.29) was not. We propose a modified nodal status that designates supraclavicular node as regional: m-N0 (5-year survival = 79 %; n = 251); m-N1 (5-year = 56 %; n = 212); m-N2 (5-year = 30 %; n = 114); m-N3 (5-year = 18 %; n = 52); m-M1 (5-year = 6.2 %; n = 36). This modified nodal staging predicts survival better than the current staging system.

Conclusions

The modification of supraclavicular lymph node from nonregional to regional in the 7th UICC classification of ESCC may allow for better stratification of overall survival.     

Is the laparoscopic approach to colectomy safe for the morbidly obese?

Background

The feasibility and safety of laparoscopic colectomy (LC) for morbidly obese patients has not been reported previously. This study aimed to assess the clinical outcomes of patients with a body mass index (BMI) of 40 kg/m³ or more who undergo laparoscopic colorectal surgery.

Methods

Prospectively accrued data for patients with a BMI of 40 kg/m³ or more (group A) who undergo LC were compared with those for patients with BMI lower than 30 kg/m³ (group B) matched for year of surgery, indication, operating surgeon, and type of procedure.

Results

Each group had 36 patients. The group A patients were significantly younger (54 vs. 61 years; P = 0.04), had higher American Society of Anesthesiology (ASA) scores (P = 0.001), and had diabetes mellitus (P = 0.04). The indications for surgery and the operations performed were similar. The two groups had similar operating times (177.9 vs. 136.4 min; P = 0.12), estimated blood losses (222.3 vs. 157 ml; P = 0.1), median lengths of hospital stay (LOS) (4.5 vs. 4 days; P = 0.2), and returns of bowel function (4.2 vs. 3.9 days; P = 0.45). Group A had significantly longer incisions (6.9 vs. 5 cm; P = 0.02). Conversions (5 vs. 3 patients; P = 0.7), readmissions (12 vs. 6 patients; P = 0.46), reoperations (5 vs. 3 patients; P = 0.17), wound infections (7 vs. 2 patients; P = 0.14), anastomotic leaks (3 vs. 2 patients; P = 0.7), and abdominal abscesses (3 vs. 2 patients; P = 0.7) were more predominant in group A, although the differences did not reach statistical significance.

Conclusions

Laparoscopic colectomy is feasible for morbidly obese patients and results in recovery of intestinal function and LOS equivalent to that for nonobese patients. As expected, morbidity and conversion rates are higher for morbidly obese patients undergoing LC than for nonobese patients.     

Incidental Thyroid Carcinoma by FDG-PET/CT: A Study of Clinicopathological Characteristics

Background

The rising incidence of incidental thyroid carcinoma (ITC) detected during fluoro-2-deoxy-d-glucose (FDG)-positron emission tomography (PET)/computed tomography (CT) scanning poses a challenge to clinicians. The present study aims to critically evaluate the clinicopathological characteristics of ITC detected by FDG-PET/CT.

Methods

Among the 557 patients managed at our institution, 40 (7.2%) patients were identified as having ITC. Of these, 22 patients had their tumor detected by FDG-PET/CT (PET group) and 11 by ultrasonography (USG group). Additional bedside ultrasonography ± fine-needle aspiration (FNA) was done in all patients at their clinic visit. The clinicopathological characteristics were compared between the PET and USG groups.

Results

The PET group had significantly more patients with history of nonthyroidal malignancy (P < 0.001). Papillary carcinoma was the most common histological type in both groups. Despite having similar histological and prognostic features including tumor size, tumor multifocality, capsular invasion, extrathyroidal extension, and lymph node metastases, tumor bilaterality (or presence of contralateral tumor focus) was significantly more frequent in the PET than the USG group (P = 0.04). The tumors were also more advanced by the tumor–node–metastasis (TNM) staging system in the PET group (P = 0.021). None of the contralateral tumor foci were evident preoperatively. One patient in the USG group developed metastatic thyroid carcinoma in neck lymph nodes 28 months after thyroid resection.

Conclusion

ITC by FDG-PET/CT had higher incidence of tumor bilaterality than those detected by ultrasonography. Total thyroidectomy should be considered for ITC detected by FDG-PET/CT even for tumor size <10 mm.     

Impact of total PSA, PSA doubling time and PSA velocity on detection rates of 11C-Choline positron emission tomography in recurrent prostate cancer

Purpose

To evaluate the effect of total PSA (tPSA) and PSA kinetics on the detection rates of ¹¹C-Choline PET in patients with biochemical recurrence (BCR) after radical prostatectomy (RP) or external beam radiotherapy (EBRT).

Methods

We included 185 patients with BCR after RP (PSA >0.2 ng/ml) or after EBRT (ASTRO definition). After injection of 400 MBq ¹¹C-Choline i.v., a scan was made using the ECAT HR + PET camera with CT fusion images or Siemens mCT PET/CT. Biopsy-proven histology, confirmative imaging (CT or bone scan) and/or clinical follow-up (PSA) were used as composite reference. Statistical analysis was performed using PASW Statistics 18.

Results

¹¹C-Choline PET was positive in 124/185 cases (65 %) (in 22/61 (36 %) after RP, 102/124 (82 %) after EBRT). In 79 patients a local recurrence was identified, and 45 patients showed locoregional metastases on PET/CT. In 20 cases a proven false-negative PET scan was observed. Positive PET scans were confirmed by histology in 87/124 (70 %) cases, by confirmatory imaging in 34/124 (28 %) and by clinical follow-up after salvage treatment in 3 (2 %) cases. The ROC analysis to detect a recurrence showed significant difference in area under the curve (AUC) of tPSA 0.721(p < 0.001) and PSA velocity 0.730 (p < 0.001). PSA doubling time showed no significant difference with an AUC of 0.542 (p = 0.354). Detection rates are <50 % in tPSA <2 ng/ml and/or PSA velocity <1 ng/ml/year.

Conclusions

Total serum PSA and PSA velocity have significant effect on the detection rates of ¹¹C-Choline PET/CT in men with a BCR after RP or EBRT.     

A two-centre blinded randomised control study comparing the Lichtenstein patch, Perfix® plug and ProLoop® plug in the repair of primary inguinal hernia

Introduction

Mesh plug is an established and effective method for repair of inguinal hernia. The ProLoop plug^® (Atrium) is a recently developed mesh plug with a novel configuration, which may offer advantages over the standard Prefix plug^® (Bard) or the Lichtenstein repair. This two-centre double-blinded randomised control trial assessed the short- and medium-term outcomes, comparing the above three methods.

Patients and methods

Consecutive patients over the age of 18 years with primary unilateral inguinal hernia were randomised to receive a Lichtenstein tension free mesh repair (LTFM), Perfix^® plug (Bard) (PF) or ProLoop^® plug (Atrium) (PL) repair. Follow-up was at 2 weeks, 6 months and 12 months. Endpoints were operative time, hospital stay, bodily pain scores, return to daily activity and complications.

Results

A total of 295 consecutive patients were recruited to the study. Ninety-three patients were randomised to receive PL plug repairs, 101 PF plug repairs and 101 LTFM repairs. There was no significant difference among the three groups in terms of age, sex or BMI. There was no significant difference among the groups in terms of operative time (PL vs PF P = 0.92; PL vs LTFM P = 0.52), hospital stay (PL vs PF P = 0.74; PL vs LTFM P = 0.44), bodily pain scores (at 12 months PL vs PF P = 0.84, PL vs LTFM P = 0.85, PF vs LTFM P = 0.16), complication rates or return to daily activity.

Conclusions

The ProLoop^® plug (Atrium) is a safe and effective method of repairing primary inguinal hernias. Its novel lightweight configuration does not increase the risk of recurrence when compared to thicker mesh plugs, and it may offer benefit in terms of long-term patient comfort. The ProLoop^® plug (Atrium) represents a new effective alternative to the established mesh repairs.     

Prognostic Impact of [18F] FDG-PET in Operable Breast Cancer Treated with Neoadjuvant Chemotherapy

Background

This study aimed to evaluate the usefulness of serial [¹⁸F] 2-fluoro-2-deoxy-d-glucose–positron emission tomography ([¹⁸F] FDG-PET) in potentially operable breast cancer with neoadjuvant chemotherapy.

Methods

Serial positron emission tomography was undertaken in 66 breast cancer patients who comprised a subset of the population in a phase III randomized neoadjuvant trial at National Cancer Center, Korea. We assessed the peak standardized uptake value (SUVp) in the primary tumor and axillary nodes before and after neoadjuvant chemotherapy and calculated the reduction rate (RR) of the SUVp. By means of a receiver operating characteristic curve, we identified an optimal cutoff value for the RR for predicting the pathologic response and evaluated the prognostic power of this cutoff value.

Results

Ten patients (15.2%) experienced a pathologic complete response (pCR) in the primary tumor, and 19 patients (28.8%) experienced a pCR in the axillary nodes. The mean RR of the SUVp in primary tumors was 70.3% ± 28.7%, and this value was significantly different by the pathological response (89.2% ± 11.1% in pCR vs. 66.9% ± 29.6% in non-pCR, P < .001). When 84.8% of the RR was used as a cutoff value for the pCR, sensitivity and specificity was 70.0% and 69.6%, respectively. Ten patients (15.2%) developed recurrent disease at a median follow-up period of 61.5 (range, 13.5–71.8) months. In a univariate analysis, the 5-year disease-free survival (DFS) was correlated with the clinical T stage (91.1% in T1/2 vs. 71.4% in T3/4, P = .02), HER-2 status (77.8% in positive vs. 96.9% in negative, P = .03), and the 84.8% RR of the SUVp in the primary tumor (95.8% vs. 78.5%, P = .04). HER-2 positivity was a significant independent prognosticator in the multivariate analysis (hazard ratio 8.73, 95% confidence interval 1.03–73.84, P = .04). The presence of a pCR in the primary tumor or nodes was not a prognostic factor in this subset of patients. The RR of the SUVp in the axillary nodes was not correlated with the nodal pCR and DFS.

Conclusions

The RR of the SUVp in the primary tumor was correlated with the pathologic response and DFS. This study suggests the possible prognostic value of the RR in positron emission tomography by neoadjuvant chemotherapy.