2-Fluoro-2-deoxy-D-glucose positron emission tomography imaging is predictive of pathologic response and survival after preoperative chemoradiation in patients with esophageal carcinoma

BACKGROUND: The current study was performed to assess the value of 2-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) in predicting the pathologic response and survival of patients with esophageal carcinoma treated with preoperative chemoradiation (CRT) and tumor resection. Preliminary reports suggest that FDG-PET may be predictive of the response of esophageal carcinoma patients to preoperative CRT. METHODS: Eighty-three patients with resectable esophageal carcinoma who underwent preoperative CRT and FDG-PET and tumor resection were evaluated for pathologic response to CRT, percent residual tumor, and survival. RESULTS: The majority of patients in the current study were men (74 of 83 patients; 89%). Most tumors were adenocarcinomas (73 of 83 tumors; 88%) and clinical (EUS)T3/4 (69 tumors; 83%) or N1 (46 tumors; 55%). FDG-PET after preoperative CRT identified pathologic responders but failed to rule out microscopic residual tumor in 13 of 73 cases (18%). Pathologic response was found to correlate with the post-CRT FDG-PET standardized uptake value (SUV) (P = 0.03) and a post-CRT FDG-PET SUV of or 4 was found to be the only preoperative factor to correlate with decreased survival (2-year survival rate of 33% vs. 60%; P = 0.01). On univariate Cox regression analysis, only post-CRT FDG-PET was found to be correlated with post-CRT survival (P = 0.04). CONCLUSIONS: Post-CRT FDG-PET was found to be predictive of pathologic response and survival in patients with esophageal carcinoma who undergo preoperative CRT. Esophagectomy should still be considered even if the post-CRT FDG-PET scan is normal because microscopic residual disease cannot be ruled out.     

The metabolic response using F-fluorodeoxyglucose-positron emission tomography/computed tomography and the change in the carcinoembryonic antigen level for predicting response to pre-operative chemoradiotherapy in patients with rectal cancer

Background and purpose

To predict tumor regression in pre-operative chemoradiotherapy (CRT) using ¹⁸F-fluorodeoxyglucose-positron emission tomography/computed tomography (PET/CT) and serum carcinoembryonic antigen (CEA) in patients with rectal cancer.

Materials and methods

The metabolic response of the tumor was assessed by determining the maximal standardized uptake value (SUV_max), absolute difference (ΔSUV_max), and SUV reduction ratio (SRR) on pre- and post-CRT PET/CT scans. The serum CEA, absolute difference (ΔCEA), and the CEA reduction ratio (CRR) were also determined. A receiver-operating characteristic (ROC) curve was generated.

Results

Of all seventy two patients, mean pre- and post-CRT SUV_max was 14.9 and 5.8, respectively. The mean pre- and post-CRT CEA level was 15.5 ng/ml and 5.4 ng/ml, respectively. Forty-three patients (59.8%) were classified as responders (Dworak’s tumor regression grade 3-4) and 36 patients (50%) achieved tumor down-staging. ROC analysis showed that both post-CRT SUV_max and SRR were predictive factors for responders (p = 0.03 and p = 0.02, respectively). A threshold of post-CRT SUV_max was 5.4 and that of SRR was 53.1%. Pre-CRT SUV_max, ΔSUV_max, and all parameters in regard to CEA were not significant in ROC analysis.

Conclusions

The post-CRT SUV_max and SRR are potential factors for predicting tumor response in pre-operative CRT. The patients with lower post-CRT SUV_max and higher SRR could be expected to achieve maximum tumor regression after pre-operative CRT in this study.     

Survivin expression can predict the effect of chemoradiotherapy for advanced lower rectal cancer

Background

Chemoradiotherapy (CRT) has been used to improve local control and survival in patients with advanced rectal carcinoma. However, a significant proportion of patients show poor response to adjuvant CRT. We thus investigated the usefulness of survivin expression as a predictive marker of the CRT response and its characteristics.

Methods

Forty-three patients with lower rectal cancer who underwent CRT were investigated. All patients received preoperative CRT consisting of TS-1 concurrent with 40 Gy of pelvic irradiation followed by curative resection. The relationship between clinical response, or pathological response, and the expression of survivin of pre-CRT biopsy specimens was evaluated by immunohistochemistry and compared with post-CRT expression.

Results

Positive expression of survivin was observed in 26 of 43 patients (60 %) in pre-CRT specimens. Survivin was positively expressed in 77 % of stable disease cases, and 43 % of partial response (p < 0.05). Regarding the correlation between pathological response and survivin expression, positive expression of survivin was recognized in 75 % (18 of 24) of Grade 0 + 1 cases, 50 % (7 of 14) of Grade 2 cases, and 20 % (1 of 5) of Grade 3 cases. A reverse correlation was recognized between pathological responses and survivin expression (p < 0.05). There were differences in the tumor differentiation between the survivin-positive group and the negative group (p < 0.05). The expression concordance rate was 66 % between pre- and post-CRT tissues. In post-CRT tissues, nuclear survivin expression disappeared completely and cytoplasmic expression increased, especially in responder cases.

Conclusion

Survivin expression in biopsy could be an important predictive factor of preoperative CRT response.     

Monitoring of Tumor Response to Neoadjuvant Radio-Chemotherapy of Esophageal Carcinoma by F-18-FDG-PET

Introduction Esophageal carcinoma is an aggressive malignancy. Thelong-term survival of patients with locoregionally advanceddisease treated with surgery alone ranges between 40%and 4% with median times of survival of 9–29 months[1?6].Because of such poor results additional chemotherapy andradiotherapy have been evaluated[7?10]. There is contin-uing discussion under which conditions such multimodaltherapy regimens can mean a bene?t in terms of longersurvival[4,8?11]. A multimodal therapy o…     

Regional radiotherapy versus an axillary lymph node dissection after lumpectomy: a safe alternative for an axillary lymph node dissection in a clinically uninvolved axilla in breast cancer. A case control study with 10 years follow up

Background

To correlate the metabolic changes with size changes for tumor response by concomitant PET-CT evaluation of lung cancers after radiotherapy.

Methods

36 patients were studied pre- and post-radiotherapy with¹⁸FDG PET-CT scans at a median interval of 71 days. All of the patients were followed clinically and radiographically after a mean period of 342 days for assessment of local control or failure rates. Change in size (sum of maximum orthogonal diameters) was correlated with that of maximum standard uptake value (SUV) of the primary lung cancer before and after conventional radiotherapy.

Results

There was a significant reduction in both SUV and size of the primary cancer after radiotherapy (p < 0.00005). Among the 20 surviving patients, the sensitivity, specificity, and accuracy using PET (SUV) were 94%, 50%, 90% respectively and the corresponding values using and CT (size criteria) were 67%, 50%, and 65% respectively. The metabolic change (SUV) was highly correlated with the change in size by a quadratic function. In addition, the mean percentage metabolic change was significantly larger than that of size change (62.3 ± 32.7% vs 47.1 ± 26.1% respectively, p = 0.03)

Conclusion

Correlating and incorporating metabolic change by PET into size change by concomitant CT is more sensitive in assessing therapeutic response than CT alone.     

Mutational and Clinical Predictors of Pathologic Complete Response in the Treatment of Locally Advanced Rectal Cancer

Purpose

Preoperative chemoradiation (CRT) for locally advanced rectal adenocarcinoma achieves pathologic complete response (pCR) in 8–20 % of patients. Mutations in critical cancer genes may contribute to lack of pCR. We retrospectively evaluated our institutional experience to determine potential mutational and clinical predictors of pCR in patients treated with CRT.

Methods

Patients with locally advanced rectal adenocarcinoma treated with preoperative CRT (n?=?79) were identified. A clinical cancer genotyping assay evaluated 140 hotspot mutation sites across 15 cancer genes in 47 patients with sufficient tissue. Mutational profiles were compared in pre- and post-CRT specimens and with pCR rate. Clinical variables were evaluated using logistic regression.

Results

Genotyping identified mutations in KRAS (43 %), APC (17 %), BRAF (4 %), NRAS (4 %), PIK3CA (4 %), and TP53 (11 %). In the entire cohort, 21.5 % had a pCR. No patients with BRAF, NRAS, APC, or TP53 achieved a pCR. pCR rate was 23.5 % (4/17) in wild-type tumors versus 3.3 % (1/30) in those with a mutation. There was no difference in the mutation rates in pre- versus post-CRT specimens. On univariate analysis, clinical predictors of pCR included post-RT carcinoembriogenic antigen level of ≤2.5 and smaller tumor size. No patients with a pCR developed recurrence.

Conclusion

Patients without mutations in commonly mutated cancer genes may be associated with a higher likelihood of having a pCR after preoperative CRT. This should be confirmed in a prospective study.     

18F-FDG PET-CT全身显像肠道高浓聚的临床意义分析

目的：评价PET-CT全身显像肠道摄取18F-FDG的临床意义.方法：本研究回顾性分析我院PET/CT中心2010年7月-2011年6月2387例检查者中肠道出现18F-FDG高代谢灶的227例检查者,通过病理结果及相关影像学检查及临床随访,确定最终结果.结果：227例肠道高浓聚中,局灶性浓聚165例,其中恶性病灶49例,总恶性率为29.70％,分组恶性率分别为体检组为8.51％,肠外原发肿瘤组为13.11％,查找原发病灶组为43.59％,临床怀疑为肠道肿瘤组为68.97％.弥漫性肠道代谢增高者62例,全部为生理性摄取或炎性改变.局灶性病灶中良性与恶性组SUV无统计学差异.结论：18F-FDG PET-CT全身显像对肠道肿瘤检出具有重要的意义,但其良恶性鉴别不能单纯依靠SUV,其病史在诊断中也具有非常重要的作用,最终诊断依靠肠镜活检.     

Whole body 18FDG-PET and the response of esophageal cancer to induction therapy: results of a prospective trial.

PURPOSE: Whole-body 18F-fluorodeoxyglucose ([18F]FDG) positron emission tomography (PET) imaging before and after induction therapy was prospectively evaluated in patients with esophageal cancer to determine whether changes in PET images could measure response to therapy. PATIENTS AND METHODS: Between April 1997 and April 1999, 39 patients (34 men and five women; median age, 59 years; range, 36 to 76 years) with esophageal cancer were prospectively enrolled in a single-institution clinical trial of staging, including PET, induction therapy, restaging including PET, and esophagectomy. All patients undergoing esophagectomy after induction therapy (n = 17) were followed either to recurrence, to death, or through a disease-free interval of at least 24 months. RESULTS: PET after standard staging studies and before therapy imaged undetected sites of metastatic disease in six patients (15%). Restaging (including PET) after induction therapy did not identify any patients with disease progression or any patients with loco-regionally unresectable disease at exploration. The median decrease in the standardized uptake value (SUV) during induction therapy was 59%. After R0 esophagectomy, the 2-year disease-free and overall survival was 38% and 63%, respectively, among patients who had a less than 60% decrease in SUV, and 67% and 89%, respectively, among patients who had a greater than 60% decrease in SUV (P =.055 and P =.088, respectively). CONCLUSION: Compared with conventional imaging, PET detects additional sites of metastatic disease at initial evaluation. After induction therapy, PET did not add to the estimation of loco-regional resectability and did not detect new distant metastases. However, changes in [18F]FDG PET may predict disease-free and overall survival after induction therapy and resection in patients with esophageal cancer. Further evaluation in larger trials is warranted.     

Neck dissection after chemoradiotherapy for oropharyngeal and hypopharyngeal cancer: the correlation between cervical lymph node metastasis and prognosis

Background

Recently, the role of chemoradiotherapy (CRT) for preserving organs in the treatment of head and neck cancer has been increasing. However, the indication for post-CRT neck dissection (ND) and its surgical extent is still controversial. The purpose of this study was to discuss the indications for post-CRT ND and the proper extent of the surgical procedure.

Methods

We performed a retrospective analysis on N2–3 oropharyngeal and hypopharyngeal squamous cell carcinoma (OHSCC) patients treated with CRT in our institute from 1995 to 2008, and determined the prognostic impact of post-CRT ND and the distribution of cervical lymph node (CLN) metastasis based on the pathological results of ND.

Results

The patients without pathological CLN metastases had good prognoses, whereas patients with pathological CLN metastases exhibited a significantly high recurrence rate (P = 0.033). Based on the pathological results of ND, performing selective ND at levels II–IV can contain 88 and 85 % of CLN metastasis of the oropharynx and hypopharynx, respectively. In all cases, when pathological CLN metastases were found at level V in ND following CRT, distant metastases developed.

Conclusions

The presence of pathological CLN metastasis affects prognosis, but also a diffuse distribution of CLN metastasis worsens prognosis; that is, the presence of CLN metastasis at level V after CRT appears to be an indicator of distant metastasis. Post-CRT ND may not make sense as a salvage intervention for improving the prognosis in such situations. We concluded that the proper extent of post-CRT ND of OHSCC is selective ND including levels II–IV.     

Response to chemotherapy estimates by FDG PET is an important prognostic factor in patients with Ewing sarcoma

Background

Response to chemotherapy is a prognostic factor in patients with Ewing sarcoma (ES); the role of FDG PET to predict response in these patients has not been thoroughly investigated. We evaluated the diagnostic accuracy and the potential of FDG PET to predict response to chemotherapy (CHT).

Materials and methods

We analyzed data of 50 patients with ES (median age 12.6 years). All patients were treated with neoadjuvant CHT, and underwent surgery for local control. All patients had ¹⁸F-FDG PET/CT at diagnosis and after induction CHT, prior to local control. We compared response assessed by histopathology with FDG PET using standard uptake values (SUVs).

Results

Median SUV at diagnosis (SUV I) was 5 (range 1.2–17), and median SUV after neoadjuvant chemotherapy (SUV II) was 1.8 (range 0–8.4). Median SUV II/I ratio was 0.3 (range 0–1). SUV at diagnosis was significantly lower in patients with good histological response than in patients with poor histological response (median 3.8 vs. 7.2, p 0.02). We found a significant correlation between SUV II and outcome; the positive predictive value of an SUV II ≤ 2.5 for favorable response was 84.21 %, and the median SUV II was significantly higher in patients with disease progression (2.3 vs. 1.6, p = 0.04). In multivariate analysis, necrosis and SUV II were significant predictors of outcome.

Conclusions

¹⁸F-FDG PET demonstrates high diagnostic accuracy for response to initial chemotherapy in patients with ES and it correlates with outcome. The role of FDG PET in predicting response and outcome should be further investigated.

     

Predictive and prognostic value of early response assessment using 18FDG-PET in advanced non-small cell lung cancer patients treated with erlotinib

Background

[18F]fluorodeoxyglucose (FDG)-PET is being evaluated as a tool for the early detection of response to various targeted agents in solid tumors. The aim of this study was to evaluate the predictive value of PET response after 2 days of erlotinib in unselected pretrated patients with stage IV NSCLC.

Patients and methods

FDG-PET/CT scans were conducted at baseline and after 2 days of erlotinib, with a CT evaluation performed at baseline and after 45–60 days of therapy. PET responses were evaluated by quantitative changes on SUVmax tumor/non-tumor ratio and classified according to EORTC criteria. PET responses were compared with RECIST responses and related to progression-free (PFS) and overall (OS) survival. Erlotinib effects on glucose uptake were also studied in a panel of NSCLC cell lines.

Results

Fifty-three patients were enrolled. At 2 days of erlotinib, 20 (38 %) patients showed partial metabolic response (PMR), 25 (47 %) had stable metabolic disease (SMD) and 8 (15 %) had progressive metabolic disease (PMD). All patients with PMD had confirmed RECIST progression at 45–60 days. Patients with early PMR and SMD had significantly longer PFS (p < 0.001 and p = 0.001, respectively) and OS (p = 0.001 for both) than PMD patients.

Conclusions

FDG-PET assessment after 2 days of erlotinib could be useful to identify early resistent patients and to predict survival in unselected NSCLC pretreated population.     

The clinical application of 18F‐fluorodeoxyglucose positron emission tomography to predict survival in patients with operable esophageal cancer

BACKGROUND:

Metabolic tumor activity using ¹⁸F‐fluorodeoxyglucose positron emission tomography (FDG‐PET) was believed to have a predictive value for patient outcome in malignancies. The objective of the current study was to assess the prognostic effectiveness of the highest standardized uptake value (SUV) in the primary or regional area (peak SUV) and the number of PET‐positive lymph nodes in esophageal cancer.

METHODS:

The authors retrospectively reviewed their experience with 184 consecutive esophageal cancer patients imaged preoperatively using FDG‐PET scanning.

RESULTS:

The median peak SUV was 4.5 (range, 1.4‐21.9). The survival curve was analyzed using the median peak SUV as the cutoff value. Comparison of each group and clinicopathologic characteristics revealed significant associations between peak SUV and each of the following factors: tumor status (P < .001), lymph node status (P < .001), metastatic status (P < .05), stage of disease (P < .001), number of PET‐positive lymph nodes (P < .001), and the number of histologically positive lymph nodes (P < .001). The 5‐year overall survival (OS) rate for patients having FDG uptake with a peak SUV ≥4.5 was 47% and that for patients with a peak SUV <4.5 was 76% (P < .0001). On multivariate survival analysis using the Cox proportional hazards model, peak SUV and the number of PET‐positive lymph nodes were found to be independent predictive factors for OS. The number of PET‐positive lymph nodes was a single prognostic factor predicting both disease‐free survival and OS.

CONCLUSIONS:

Pretreatment PET cannot only potentially diagnose the extent of disease, but also may be predictive of patient survival after esophageal cancer resection. Cancer 2009. © 2009 American Cancer Society.     

Response to trastuzumab by HER2 expressing breast tumour xenografts is accompanied by decreased Hexokinase II, glut1 and [18F]-FDG incorporation and changes in 31P-NMR-detectable phosphomonoesters

Purpose

Trastuzumab, effective in about 15 % of women with breast cancer, downregulates signalling through the Akt/PI3K and MAPK pathways. These pathways modulate glucose and phospholipid metabolism which can be monitored by [¹⁸F]FDG-PET and ³¹P-NMR spectroscopy, respectively. Here, the relationship between response of HER-2 overexpressing tumours and changes in [¹⁸F]-FDG incorporation and ³¹P-NMR-detectable phosphomonoesters were examined.

Experimental

Xenografts derived from HER2-overexpressing MDA-MB-453 human breast tumour cells were grown in SCID mice, treated with trastuzumab for 15 days, then [¹⁸F]-FDG uptake determined and ³¹P-NMR carried out on chemical extracts of the tumours. Western blots were carried out to determine protein expression of Hexokinase II and glut1.

Results

[¹⁸F]-FDG incorporation, Hexokinase II and glut1 protein expression and the concentration of phosphocholine and phosphoethanolamine in chemical extracts subjected to ³¹P-NMR were significantly decreased in the xenografts in the trastuzumab-treated mice compared with xenografts from the PBS-injected group.

Conclusions

Changes in FDG incorporation and ³¹P-NMR spectral changes can accompany response of HER2-expressing breast cancer xenografts to trastuzumab. This is the first study to show parallel changes in [¹⁸F]FDG- and ³¹P-NMR-detectable metabolites accompany response to targeted anticancer treatment.     

Residual metabolic tumor activity after chemo-radiotherapy is mainly located in initially high FDG uptake areas in rectal cancer

Purpose

Recent literature suggests that tumor cells and areas within tumors with a high initial FDG uptake might be more resistant to (chemo)radiotherapy ((C)RT). This study was undertaken to test this hypothesis in rectal cancer using rigid and non-rigid image registration.

Patients and methods

Twenty-eight patients, diagnosed with locally advanced rectal cancer and referred for pre-operative treatment with CRT were included in this study. All patients underwent FDG-PET-CT imaging prior to and after CRT. Rigid and non-rigid image registration was performed to compensate organ deformations between the pre- and post-treatment PET-CT scans. The tumor was contoured on both PET-scans using SUV iso-contouring based on the SBR-method. The voxels with residual increased FDG uptake were studied and correlated to their pre-treatment FDG uptake level. Two SUV-volume-histograms were made based on the pre-treatment PET-data, one for the voxels within the pre-treatment tumor PET-based iso-contour and one for the voxels within the PET-based iso-contour of the residual tumor non-rigidly registered onto the pre-treatment scan.

Results

For the voxels with a pre-treatment FDG uptake of >50% of SUV_max, 70.6 ± 5.6% of the voxels were still metabolic active in the residual tumor, whereas for voxels with an FDG uptake of <50% of SUV_max only 51.1 ± 6.7% were present in the metabolic active residual tumor.

Conclusion

This study presents areas in rectal tumors with an initially high FDG uptake to be most likely to show residual disease after CRT. This could indicate a higher (C)RT-resistance for tumor regions with a high FDG uptake prior to treatment.     

18F-Fluorodeoxyglucose positron emission tomography optimizes neoadjuvant chemotherapy for primary breast cancer to achieve pathological complete response

Background

To assess the usefulness of positron emission tomography combined with computed tomography using ¹⁸F-fluorodeoxyglucose (FDG PET/CT) for optimizing chemotherapy during neoadjuvant chemotherapy for primary breast cancer.

Methods

One hundred and eight patients (110 tumors) with breast cancer (??2?cm, stages II and III) received neoadjuvant chemotherapy consisting of an anthracycline-based regimen and taxane. The maximal value of the baseline standardized uptake value (SUV) and the change in SUV after four cycles of an anthracycline-based regimen relative to baseline SUV were assessed for predicting pathological complete response (pCR) after sequential taxane.

Results

Tumors with pCR had significantly higher baseline SUV (9.3?±?3.7 SD) compared to those with non-pCR (7.2?±?3.8 SD) (p?=?0.02), but there was a considerable overlap between two groups. On PET scan after four cycles of chemotherapy, thirty-three patients (33.7%) with a 72.1% or greater reduction in SUV were considered as responders and the performance in predicting pCR had a sensitivity of 88.9% and specificity of 78.7%.

Conclusion

The baseline SUV could not be a useful indicator for predicting pCR due to the wide range in sensitivity. On the other hand, a relative change in SUV after completion of an anthracycline-based regimen could be useful for predicting pCR.     

The contribution of neck dissection for residual neck disease after chemoradiotherapy in advanced oropharyngeal and hypopharyngeal squamous cell carcinoma patients

Background

Planned neck dissection after chemoradiotherapy (CRT) has remained controversial in advanced oro- and hypopharyngeal squamous cell carcinoma (OHSCC) patients. We evaluated the survival contribution of neck dissection (ND) in OHSCC patients with residual nodal disease following CRT.

Methods

We retrospectively evaluated 84 OHSCC patients with N2–3 disease treated at Aichi Cancer Center Hospital between 1995 and 2006. ND after CRT was performed for residual neck disease in 36 patients, but not in 48 patients to achieve a complete response. These two groups were analyzed in terms of both overall survival (OS) and regional control (RC), and surgical complications were evaluated.

Results

The 5-year OS was 76.7 % [95 % confidence interval (CI) 58.8–87.6] for the ND group and 73.9 % (58.6–84.3) for the non-ND group (P = 0.883). The 5-year RC was 91.6 % (76.1–97.2) for the ND group and 81.1 % (65.4–90.2) for the non-ND group (P = 0.252). Stratified by primary tumor site, the 5-year RC was 96.3 % (76.5–99.5) for the ND group, and 78.6 % (58.0–89.9) for the non-ND group (P = 0.072) in oropharyngeal squamous cell carcinoma patients, and 77.8 % (36.5–93.9) for the ND group and 85.9 % (54.0–96.3) for the non-ND group (P = 0.541) in hypopharyngeal squamous cell carcinoma patients. In addition, the complications after ND were tolerable.

Conclusions

We demonstrated that ND was feasible, safe, and correlated with clinical outcomes in OHSCC patients with residual nodal disease after CRT.     

Correlation of molecular response as measured by 18-FDG positron emission tomography with outcome after chemoradiotherapy in patients with esophageal carcinoma

PURPOSE: To determine whether 18-fluorodeoxyglucose positron emission tomography (PET) computed tomography scans predict the pathologic complete response and disease-free and overall survival in patients with esophageal carcinoma undergoing definitive or preoperative chemoradiotherapy. METHODS AND MATERIALS: The records of patients with esophageal carcinoma presenting for definitive or preoperative treatment and undergoing pre- and post-treatment 18-fluorodeoxyglucose PET-computed tomography scans were retrospectively reviewed. The histologic type, T stage, and nodal status were the variables investigated to determine a relationship with the baseline standardized uptake value (SUV) of the primary tumor at diagnosis. We also attempted to determine whether a relationship exists between the percent decrease in SUV and a pathologic complete response, overall and disease-free survival. RESULTS: A total of 81 patients, 14 women and 67 men, underwent 18-fluorodeoxyglucose PET-computed tomography scanning before treatment and 63 also had post-treatment scans. T stage and tumor location predicted in univariate, but not multivariate, analysis for the initial SUV. Of the patients with a postchemoradiotherapy SUV of <2.5, 66% had tumor in the surgical specimen and 64% of patients had positive lymph nodes at surgery that were not imaged on the postchemoradiotherapy PET scan. A trend existed for post-treatment SUV and the days from radiotherapy to surgery to predict for a pathologic complete response (p = 0.09 and p = 0.08, respectively). The post-treatment SUV predicted for disease-free survival in the definitive chemoradiotherapy group (p = 0.01). CONCLUSIONS: A correlation was found between the depth of tumor invasion and the baseline SUV. The post-treatment SUV predicted for disease-free survival in the definitive chemoradiotherapy group. Caution should be exercised in using post-treatment PET scans to determine the necessity for surgical resection.     

Lung Carcinoma Presenting as an Obstructive Jaundice: Case Series with Literature Review

Background

The management of esophageal cancer continues to be riddled with controversies, even as more and more clinical trials are being conducted amid a remarkable change in histology and epidemiology. Significant variations exist in the surgical treatment of esophageal cancer, and there is no consensus on the best surgical approach or the extent of lymphadenectomy. Interestingly, extended esophagectomy (three-field lymphadenectomy) has not been compared with transhiatal esophagectomy in a head-to-head fashion.

Methods

We did a retrospective comparison of 111 consecutive patients who underwent curative resection for carcinoma of the esophagus, via either a transthoracic esophagectomy with three-field dissection (3F TTE) or transhiatal esophagectomy (“THE”) at a regional cancer center in South India over a period of 5 years from 2002 to 2006. The primary outcome measure was 5-year disease-free (DFS) and the overall survival (OS). An exhaustive analysis of the short-term outcomes was also made.

Results

The 5-year overall survival and disease-free survival were 52 and 49 % in the 3F TTE group and 37 and 37 %, respectively, in the “THE” group, which were not statistically significant. The short and the long-term outcomes in both the groups compared favorably with the other published series.

Conclusions

Our study possibly for the first time compares 3F TTE and “THE” in the management of resectable carcinoma of the esophagus. Although the survival outcomes of both the groups were not statistically different, 3F TTE did show a trend towards improved DFS and OS when compared to “THE” group. However, this being a retrospective study, the results of this analysis need to be verified in an adequately sized prospective randomized study.     

Biopsy validation of 18F-DOPA PET and biodistribution in gliomas for neurosurgical planning and radiotherapy target delineation: results of a prospective pilot study

Background

Delineation of glioma extent for surgical or radiotherapy planning is routinely based on MRI. There is increasing awareness that contrast enhancement on T1-weighted images (T1-CE) may not reflect the entire extent of disease. The amino acid tracer ¹⁸F-DOPA (3,4-dihydroxy-6-[18F] fluoro-l-phenylalanine) has a high tumor-to-background signal and high sensitivity for glioma imaging. This study compares ¹⁸F-DOPA PET against conventional MRI for neurosurgical biopsy targeting, resection planning, and radiotherapy target volume delineation.

Methods

Conventional MR and ¹⁸F-DOPA PET/CT images were acquired in 10 patients with suspected malignant brain tumors. One to 3 biopsy locations per patient were chosen in regions of concordant and discordant ¹⁸F-DOPA uptake and MR contrast enhancement. Histopathology was reviewed on 23 biopsies. ¹⁸F-DOPA PET was quantified using standardized uptake values (SUV) and tumor-to-normal hemispheric tissue (T/N) ratios.

Results

Pathologic review confirmed glioma in 22 of 23 biopsy specimens. Thirteen of 16 high-grade biopsy specimens were obtained from regions of elevated ¹⁸F-DOPA uptake, while T1-CE was present in only 6 of those 16 samples. Optimal ¹⁸F-DOPA PET thresholds corresponding to high-grade disease based on histopathology were calculated as T/N > 2.0. In every patient, ¹⁸F-DOPA uptake regions with T/N > 2.0 extended beyond T1-CE up to a maximum of 3.5 cm. SUV was found to correlate with grade and cellularity.

Conclusions

¹⁸F-DOPA PET SUV_max may more accurately identify regions of higher-grade/higher-density disease in patients with astrocytomas and will have utility in guiding stereotactic biopsy selection. Using SUV-based thresholds to define high-grade portions of disease may be valuable in delineating radiotherapy boost volumes.     

Early evaluation of neoadjuvant chemotherapy response using FDG-PET/CT predicts survival prognosis in patients with head and neck squamous cell carcinoma

Background

The purpose of this study was to investigate the possibility of early survival prediction after completion of one cycle of neoadjuvant chemotherapy (NAC) by positron emission tomography (PET)/computed tomography (CT) with ¹⁸F-fluorodeoxyglucose (FDG).

Methods

Fifty-seven patients with advanced head and neck squamous cell carcinoma (HNSCC) underwent FDG-PET/CT scans twice, before and after one cycle of NAC. We calculated the maximal standardized uptake value (SUV_max) for a primary tumor and/or metastatic lymph nodes and defined %decrease as the %difference in SUV_max between the two scans divided by that of the initial scan. Patients were classified as responders by PET (%decrease ≥55.5% or post-NAC SUV_max ≤3.5) and by RECIST (≥30% decrease in size). The local control (LC) rate and the disease-specific survival (DSS) rate were assessed between the responders and non-responders. Multivariate analysis was also performed using the Cox proportional hazards model.

Results

In univariate analysis, the PET finding of a primary site was a significant risk factor for LC and DSS rates at 2 years after completion of NAC (P = 0.03 and 0.02, respectively), but there was no difference between responders and non-responders by the RECIST criteria. In a multivariate regression analysis, the PET finding in the primary site and the definitive therapy choice were independent prognostic factors in LC, while the PET finding in the primary site was the only independent prognostic factor in DSS.

Conclusion

Our preliminary data indicate that the PET finding in the primary lesion after one cycle of NAC was an independent prognostic factor in LC and DSS in patients with HNSCC.