The standardized uptake value for F-18 fluorodeoxyglucose is a sensitive predictive biomarker for cervical cancer treatment response and survival

BACKGROUND: The objective of this study was to evaluate cervical tumor uptake of F-18 fluorodeoxyglucose (FDG) measured as the maximal standardized uptake value (SUV(max)) by positron emission tomography (PET) and its association with treatment response and prognosis in patients with cervical cancer. METHODS: The study population consisted of 287 patients with stage IA2 through IVB cervical cancer who underwent pretreatment FDG-PET studies. SUV(max), tumor volume, and sites of lymph node metastasis were recorded. Therapy included surgery, chemoradiation, or palliation. RESULTS: The mean SUV(max) was 11.4 (range, 1-50.4). The mean tumor volume by stage was 42.1 cm(3) for stage I tumors (using International Federation of Gynecology and Obstetrics [FIGO] staging criteria), 63.7 cm(3) for stage II tumors, 129.2 cm(3) for stage III tumors, and 166.2 cm(3) for stage IV tumors. There was no correlation between tumor volume and SUV(max) (correlation coefficient [R(2)] = 0.01). No significant difference in SUV(max) was observed between squamous histology (n = 247 patients) and nonsquamous histology (n = 40 patients; P = .089). Higher SUV(max) was associated with an increased risk of lymph node metastasis at diagnosis (P = .0009). A Cox proportional-hazards model for death from cervical cancer was used to evaluate tumor histology, lymph node metastasis, tumor volume, and SUV(max). The results indicated that SUV(max) was the only significant independent factor (P = .0027). Three prognostic groups were established using SUV(max). The overall survival rates at 5 years were 95% for an SUV(max) 5.2 and 13.3 (P < .0001). Increasing SUV(max) was associated with persistent abnormal FDG uptake in the cervix on 3-month FDG-PET studies in 238 patients who received curative chemoradiation (P = .04). CONCLUSIONS: The SUV(max) of the cervical tumor at diagnosis was a sensitive biomarker of treatment response and prognosis for patients with cervical cancer.     

False-Positive Mediastinal Lymphadenopathy on 18F-Fluorodeoxyglucose Positron Emission Tomography and Computed Tomography after Rectal Cancer Resection: A Case Report of Thoracoscopic Surgery in the Prone Position

(18)F-fluorodeoxyglucose (FDG) positron emission tomography and computed tomography (integrated FDG PET/CT) has been used to diagnose recurrence and differentiate postoperative changes from lymph node metastasis in colorectal cancer, although its accuracy is questionable. We report a prone thoracoscopic surgery for a rectal cancer patient in which false-positive mediastinal lymph nodes were found on FDG-PET/CT. A 60-year-old man underwent a laparoscopic high anterior resection and D3 lymph node dissection for rectal cancer. The histopathological diagnosis was moderately differentiated adenocarcinoma of the rectum, stage IIIB (pT3N1M0), necessitating oral fluoropyrimidine agent S-1. After the primary surgery, a solitary mediastinal lymph node measuring 30 mm in diameter was detected, and abnormal accumulation was confirmed by FDG-PET/CT (SUV(max), 11.7). Thoracoscopic resection was performed in the prone position, but histopathological results showed no metastasis. He was subsequently diagnosed with reactive lymphadenitis. The patient was discharged on postoperative day 4 in good condition and is alive without recurrence 12 months after surgery. PET/CT is useful for the detection of colorectal cancer recurrence; however, it does have a high false-positive rate for mediastinal lymph nodes. There is a limit to its diagnostic accuracy, and one must determine the indication for surgical treatment carefully. Surgery in the prone position is a useful and minimally invasive approach to the mediastinum and allows aggressive resection to be performed.     

Pilot study of F(18)-Fluorodeoxyglucose Positron Emission Tomography/computerised tomography in Wilms' tumour: correlation with conventional imaging, pathology and immunohistochemistry

Wilms’ tumour is the second most common paediatric solid tumour. Prognosis is good although higher stage disease carries significant mortality and treatment related morbidity. In the UK, risk stratification is based on histological response to pre-operative chemotherapy. F¹⁸-Fluorodeoxyglucose Positron Emission Tomography (F¹⁸FDG-PET) is an emerging functional imaging technique in paediatric oncology. Little is known about the relationship between F¹⁸FDG-PET images and the disease process of Wilms’ tumour. We performed F¹⁸FDG-PET/CT scans in seven children with Wilms’ tumour after induction chemotherapy, immediately before surgery. The standard uptake values (SUV) of F¹⁸FDG-PET/CT images were related to conventional imaging and histopathological findings. In total seven children were studied. F¹⁸FDG-PET/CT was consistently safely performed. All tumours showed F¹⁸FDG activity. Four tumours had activity with SUV/bw max >5 g/ml. Histological examination of these active areas revealed viable anaplastic Wilms’ tumour. Furthermore, in these four tumours GLUT-1 and Ki67 immunostaining was strongly positive. Three further tumours demonstrated lower uptake (SUV/bw max <5 g/ml), which represented areas of microscopic foci of residual viable tumour mixed with post chemotherapy change. Metastatic disease was F¹⁸FDG avid in two of four children with stage four diseases. In conclusion, following chemotherapy, active Wilms’ tumour is F¹⁸FDG avid and higher SUV was seen in histologically high risk disease.     

Standardised FDG uptake: a prognostic factor for inoperable non-small cell lung cancer

The aim of this study was to investigate the relationship between standardised uptake value (SUV) obtained from [(18)F]fluorodeoxyglucose positron emission tomography (FDG PET) and treatment response/survival of inoperable non-small cell lung cancer (NSCLC) patients treated with high dose radiotherapy. Fifty-one patients were included recording stage, performance, weight loss, tumour volume, histology, lymph node involvement, SUV, and delivered radiation dose. The maximum SUV (SUV(max)) within the primary tumour was a sensitive and specific factor for predicting treatment response. Apart from SUV(max), stage and performance were also independent predictive factors for treatment response. In a multivariate disease-specific survival (DSS) analysis, SUV(max) (P = 0.01), performance status (P = 0.008) and stage (P = 0.04) were prognostic factors. For overall survival (OS), SUV(max) (P = 0.001) and performance (P = 0.06) were important prognostic factors. SUV(max) was an important prognostic factor for survival of inoperable NSCLC patients and a predictive factor for treatment response. Although the number of patients was small, the treatment was not homogeneous and the use of FDG SUV may have had constraints, we still conclude that the FDG SUV is potentially a good indicator for selecting patients for different treatment strategies.     

EGFR gene copy number in adenocarcinoma of the lung by FISH analysis: investigation of significantly related factors on CT, FDG-PET, and histopathology

It has been suggested that a high EGFR gene copy number may be an indicator of good response to EGFR tyrosine kinase inhibitor therapy and a marker of poor prognosis in NSCLC. However, imaging features related to EGFR gene copy number status in adenocarcinoma are still unknown. We therefore retrospectively analyzed CT, FDG-PET, and histopathologic slides of surgical resected lung adenocarcinoma in 132 patients. Tumor characteristics on preoperative chest-CT, such as, GGO proportions, tumor diameters, and cavitation; FDG-PET SUV(max); and histopathologically determined differentiation degrees and tumor subtypes were evaluated. EGFR gene copy number status was categorized as FISH-positive or -negative. FISH-positivity was found in 53 patients (40.2%) and was significantly more frequent in tumors with a SUV(max)>7.0 (P=0.007). Furthermore, FISH-negativity was found to be more frequent in tumors with a GGO>50% (P=0.023) and diameter <15.5mm (P=0.006) on CT, or a well-differentiated histopathology (P=0.002). Moreover, the frequency of FISH-positivity increased as SUV(max) increased (P=0.0008) and as the proportion of GGO decreased (P=0.01). SUV(max)>7.0 was an independent predictor of FISH-positive results (odds ratio, 3.941; 95% CI, 1.691-9.182; P=0.01). In conclusion, a high SUV(max) on FDG-PET was significantly related to FISH-positive results. A high proportion of GGO, small tumor diameter on CT, and a well-differentiated histopathology were more frequent in FISH-negative adenocarcinomas.     

Effects of hyperoxygenation on FDG-uptake in head-and-neck cancer.

PURPOSE: Tumor hyperoxygenation results in high response rates to ARCON (accelerated radiotherapy with carbogen and nicotinamide). The effect of hyperoxygenation on tumor metabolism using [(18)F]fluorodeoxyglucose (FDG) positron emission tomography (PET) was investigated. METHODS: Within one week, FDG-PET was performed without and with hyperoxygenation by carbogen breathing and/or nicotinamide administration in 22 patients, eligible for ARCON for head-and-neck cancer. Maximum standardized uptake values (SUV(max)) in both scans and the relative change were calculated in the primary tumor and in normal muscle. RESULTS: Alteration of the tumor oxygenation state induced profound, but variable, metabolic changes (median DeltaSUV(max) -4%; range -61% to +30%). Metabolism in normal muscle was not affected. In three patients who did not achieve local tumor control, the SUV(max) after hyperoxygenation differed less than 5% change as compared to baseline, whereas 13 of the 16 patients with local tumor control showed a larger difference (p<0.05). CONCLUSION: Given the heterogeneous response pattern of nicotinamide and carbogen on FDG-uptake in head-and-neck carcinoma, the prognostic significance of semiquantitative FDG-PET before and after hyperoxygenation remains uncertain and requires confirmation in larger clinical studies before introducing the procedure as a predictive tool for oxygenation modifying treatments.     

Composite lymphoma of Hodgkin lymphoma and mycosis fungoides: previously undescribed in the same extracutaneous site.

Mycosis fungoides (MF), diagnosed and limited to the skin, has been associated with the subsequent development of Hodgkin lymphoma (HL), most commonly of the nodular sclerosing (NS) subtype. In the previously described cases, there are none in which the extracutaneous tissue was simultaneously involved by HL and residual/relapsing MF. Here we report a case of HL, mixed cellularity (MC) subtype, arising in an inguinal lymph node in a patient with a previous diagnosis of MF. We describe the immunophenotypic, histologic and immunohistochemical findings of a composite lymphoma containing the HL, MC subtype and MT. The importance of detecting MF in addition to the HL in the extracutaneous site with available diagnostic modalities is highlighted.     

[18F]-Fluorodeoxyglucose positron emission tomography in children with neurofibromatosis type 1 and plexiform neurofibromas: correlation with malignant transformation

The objective of this study was to investigate the predictive value of [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET) in detecting malignant transformation of plexiform neurofibromas in children with neurofibromatosis type 1 (NF1). An electronic search of the medical records was performed to determine patients with NF1 who had undergone FDG-PET for plexiform neurofibroma between 2000 and 2011. All clinical, radiologic, pathology information and operative reports were reviewed. Relationship between histologic diagnosis, radiologic features and FDG-PET maximum standardized uptake value (SUV(max)) was evaluated. This study was approved by the Institutional Review Board of our institution. 1,450 individual patients were evaluated in our Multidisciplinary Neurofibromatosis Program, of whom 35 patients underwent FDG-PET for suspected MPNST based on change or progression of clinical symptoms, or MRI findings suggesting increased tumor size. Twenty patients had concurrent pathologic specimens from biopsy/excision of 27 distinct lesions (mean age 14.9 years). Pathologic interpretation of these specimens revealed plexiform and atypical plexiform neurofibromas (n = 8 each), low grade MPNST (n = 2), intermediate grade MPNST (n = 4), high grade MPNST (n = 2), GIST (n = 1) and non-ossifying fibroma (n = 1). SUV(max) of plexiform neurofibromas (including typical and atypical) was significantly different from MPNST (2.49 (SD = 1.50) vs. 7.63 (SD = 2.96), p < 0.001). A cutoff SUV(max) value of 4.0 had high sensitivity and specificity of 1.0 and 0.94 to distinguish between PN and MPNST. FDG-PET can be helpful in predicting malignant transformation in children with plexiform neurofibromas and determining the need for biopsy and/or surgical resection.     

Imbalances of chemokines,chemokine receptors and cytokines in Hodgkin lymphoma: classical Hodgkin lymphoma vs. Hodgkin-like ATLL

Classical Hodgkin lymphoma (HL) is characterized by the presence of Hodgkin and Reed-Sternberg cells (H&RS) and a prominent lymphocytic infiltration. We previously reported Hodgkin-like adult T-cell leukemia/lymphoma (HL-like ATLL) (new WHO classification). Various CXC and CC chemokines are expressed on H&RS cells and the relationships between chemokines and the chemokine receptor (R) are thought to be important for selectivity of local immunity of Th1 and Th2 T cells. To clarify the role of T-cell immunity in classical HL and Hodgkin-like ATLL, we performed gene expression profiling (chemokine, chemokine R and cytokine DNA chips) in 12 cases [classical HL, 8 cases [mixed cellularity (MC) type, 4; nodular sclerosis (NS) type, 4]; Hodgkin-like ATLL, 4 cases] and immunohistochemical staining in 29 cases (MC, 10; NS, 10; Hodgkin-like ATLL, 9). EBV-infected H&RS cells were detected in 9 of 10 cases of HL MC, 5 of 9 of HL-like ATLL and 2 of 10 HL NS. T-cell-directed chemokine thymus- and activation-regulated chemokine (TARC)- and/or macrophage-derived chemokine (MDC)-positive H&RS cells were detected in all 20 cases of HL MC and HL NS but only in 5 of 9 cases of HL-like ATLL. Interferon-gamma-inducible protein-10 (IP10)- and monokine induced by interferon-gamma (MIG)-positive H&RS cells were detected in all 10 HL MC but only in 5 of 10 cases of HL NS and 2 of 9 cases of HL-like ATLL. However, 2 of 5 cases of HL-like ATLL with EBV infection and 2 of 2 HL NS with EBV had IP10/MIG-positive H&RS cells. The chemokine expressions in H&RS cells seemed to be associated with EBV infection rather than histologic subtypes. In the DNA chip expression analysis, classical HL and HL-like ATLL had a mixed Th1/Th2-type profile, and HL MC (EBV-positive) and HL NS (EBV-negative) were differentially clustered. However, 2 cases of HL-like ATLL clustered with HL MS and the other 2 cases of HL-like ATLL clustered with HL NS. The former HL-like ATLL had EBV infection in H&RS cells, whereas the latter did not have EBV infection. This finding also suggests that EBV might influence local expression of chemokines rather than HL subtypes. Our results indicate that local immunologic disorder or imbalance appears to influence the formation of H&RS cells and that in HL-like ATLL, HTLV-1 infection might not be necessary for H&RS cell formation.     

Biological response of nasopharyngeal carcinoma to radiation therapy: a pilot study using serial 18F-FDG PET/CT scans

We used serial (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) to evaluate tumors' maximum standardized uptake value (SUV(max)) before, during, and after radiotherapy to explore the biological behavior of and response to radiation therapy in various subtypes of nasopharyngeal carcinoma (NPC). Sixty-one patients with pathologically diagnosed NPC were prospectively enrolled into the study. WHO type II(B) disease had a higher initial SUV(max) and more significant biological response at the primary site as compared with type II(A) subtype. The two subtypes of WHO type II NPC may significantly differ in their biological behavior and response to radiotherapy.     

Comparison between positron emission tomography and computed tomography in the use of the assessment of esophageal carcinoma

BACKGROUND: The role and potential value of positron emission tomography (PET) scanning in certain tumors has been widely investigated in recent years. The authors retrospectively assessed the performance of 18-F-fluorodeoxyglucose (FDG)-PET in the assessment of esophageal squamous cell carcinoma (SCC). METHODS: The results using PET were compared with those using computed tomography (CT), and these were correlated with the pathologic findings. The authors studied 32 patients with thoracic esophageal SCC who had undergone radical esophagectomy. RESULTS: Uptake of FDG in the primary tumor was found in 25 of the 32 (78.1%) cases. Comparison of the FDG uptake and the clinicopathologic findings showed that there was a significant association between the FDG uptake and each of the depth of tumor invasion (P < 0.05), occurrence of lymph node metastasis (P < 0.01), and lymphatic invasion (P < 0.01). The survival rate in cases with high FDG uptake (standardized uptake value [SUV], >3) was significantly lower than that in cases with low FDG uptake (SUV, < 3; P < 0.05). In the evaluation of lymph node staging by the detection of lymph node metastasis, FDG-PET showed 77.8% sensitivity, 92.9% specificity, and 84.4% accuracy, and CT scanning showed 61.1% sensitivity, 71.4% specificity, and 65.6% accuracy. Positron emission tomography scanning showed a high degree of accuracy in the neck, upper thoracic, and abdominal regions. However, in the mid- and lower thoracic regions, the sensitivity was very low. The smallest lymph node metastasis that was detected by FDG-PET imaging was 6 mm. The average size of lymph node metastasis that was undetected by FDG-PET scanning was 7.3 mm (range, 1-17 mm). CONCLUSIONS: In conclusion, FDG-PET may be used as a noninvasive diagnostic technique in assessing the aggressiveness of the tumor and the prognosis in patients with esophageal SCC. During the preoperative diagnostic procedures, the sensitivity, specificity, and accuracy of lymph node staging is higher with FDG-PET than with CT imaging. In view of the high specificity of FDG-PET, it also gives useful information to guide the choice of treatment of esophageal carcinoma.     

Comparison of 99mtechnetium-pertechnetate and 123iodide SPECT with FDG-PET in patients suspicious for breast cancer

PURPOSE: Breast carcinomas express the Na(+)/I() symporter and may-albeit not a routine procedure-be imaged with (123)iodide ((123)I) and (99m)technetium-pertechnetate ((99m)TcO(4)(-)) scintigraphy. The aim of our prospective study was the comparison of (99m)TcO(4)(-)--and (123)I-single-photon emission computed tomography (SPECT) with (18)F-2-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) in patients suspicious for breast cancer. METHODS: Twenty-nine (29) untreated patients suspected of having breast carcinoma were prospectively examined with thorax SPECT with (99m)TcO(4)(-) (n=19) or (123)I (n=10), respectively, and FDG-PET (n=29) prior to biopsy. Tumor-to-background ratios (TBRs) were calculated for SPECT findings. Mean and maximum standardized uptake values (SUVs) were calculated for PET findings. Findings were compared in an intra-individual lesion-to-lesion analysis. RESULTS: In 28 of 29 patients, malignancy was verified with histopathology. In imaging the primary tumor, sensitivities of (99m)TcO(4)(-)-SPECT, (123)I-SPECT, and FDG-PET were 63%, 67%, and 89%, respectively. TBR maximum was 2.6+/-1.1 in (99m)TcO(4)()-SPECT and 2.3+/-0.6 in (123)I-SPECT. In FDG-PET, mean tumor SUV was 4.1+/-4 and maximum tumor SUV was 5.4+/-5.1. In contrast to FDG-PET, (99m)TcO(4)()-SPECT was ineffective in imaging nodal and distant metastases in the thorax, and (123)I-SPECT failed in imaging lymph node infiltrations. Distant metastases were not present in patients of the (123)I group, and the value of (123)I-SPECT was not evaluated. CONCLUSIONS: In contrast to FDG-PET, (99m)TcO(4)(-) and (123)I-SPECT are ineffective in imaging breast carcinoma in clinical practice.     

The increased accumulation of [18F]fluorodeoxyglucose in untreated prostate cancer

BACKGROUND: To evaluate the clinical usefulness of [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) compared with histopathological grading, clinical stage and serum prostatic specific antigen (PSA) level in the detection and characterization of prostate cancer. METHODS: Forty-four patients with histologically proven prostate cancer and five control subjects with benign prostatic hyperplasia (BPH) were prospectively investigated with FDG-PET prior to treatment. RESULTS: By visual inspection, FDG accumulation was positive in 28 patients with prostate cancer (sensitivity 64%), whereas all were negative in the control group. FDG-PET in three patients with lymph node metastases did not show any high intrapelvic accumulations corresponding to metastatic sites. Among 12 patients with multiple bone metastases which were detected with 99m-HMDP bone scintigraphy, nine (75%) showed moderate to high FDG accumulation at the sites of bone metastases. Quantitatively, FDG accumulation in prostate cancer was significantly higher than in BPH and there was a tendency for FDG uptake of tumors to be higher with higher histological Gleason grades. Furthermore, FDG uptake in tumors with lymph node and/or bone metastasis was significantly higher than that of localized stages. However, the correlation between PSA and FDG uptake in the prostate cancer was very weak for clinical relevance. CONCLUSIONS: Although FDG-PET was not sensitive enough to detect prostate cancer in clinical use, it is suggested that glucose metabolism in prostate cancer tended to be higher in patients with tumors of advanced stages.     

Inefficacy of F-18 fluorodeoxy-D-glucose-positron emission tomography scans for initial evaluation in early-stage cutaneous melanoma

BACKGROUND: The purpose of the current study was to determine the sensitivity and specificity of initial F-18 fluorodeoxy-D-glucose-positron emission tomography (FDG-PET) scanning for detection of occult lymph node and distant metastases in patients with early-stage cutaneous melanoma. METHODS: The authors conducted a prospective nonrandomized clinical trial. Inclusion criteria were patients with cutaneous melanoma tumors > 1.0 mm Breslow thickness, local disease recurrence, or solitary intransit metastases without regional lymph or distant metastases by standard clinical evaluation. All patients underwent whole-body FDG-PET scanning before surgical therapy. Abnormal PET findings were studied by targeted conventional imaging and/or biopsy. FDG-PET scans were interpreted in a blinded fashion. Regional lymph node basins were staged by sentinel lymph node biopsy (SLNB). PET scan findings in regional lymph nodes were compared with histology of SLNB specimens. Abnormal distant PET scan findings were studied with repeat conventional scan imaging at 3-6 months and were correlated with the first site(s) of clinical disease recurrence. Blinded PET scan findings were correlated with all information to determine sensitivity and specificity. RESULTS: There were 144 assessable patients with a mean tumor depth of 2.8 mm. The median follow-up for these patients was 41.4 months. Blinded interpretations of FDG-PET scan images showed that 31 patients (21%) had signs of metastatic disease, 13 patients had probable regional lymph node metastases, and 18 patients had 23 sites of possible distant metastases. SLNB and/or follow-up demonstrated regional lymph node metastases in 43 of 184 lymph node basins in 40 patients (27.8%). Compared with all clinical information, FDG-PET scan sensitivity for detection of regional lymph node metastases was 0.21 (95% confidence [CI], 0.10-0.36) and specificity was 0.97 (95% CI, 0.93-0.99). No distant sites were confirmed to be true positive by targeted conventional imaging/biopsy at the time of presentation. Thirty-four patients (23.6%) presented with 54 foci of metastatic disease at initial disease recurrence. FDG-PET scan sensitivity for prediction of the first site(s) of clinical disease recurrence was 0.11 (95% CI, 0.04-0.23). Excluding patients with brain metastases, FDG-PET scan sensitivity for detection of occult Stage IV disease in patients was 0.04 (95% CI, 0.001-0.20) and specificity was 0.86 (95% CI, 0.79-0.92). CONCLUSIONS: FDG-PET scanning did not impact the care of patients with early-stage melanoma already staged by standard techniques. Routine FDG-PET scanning was not recommended for the initial staging evaluation in this population.     

非小细胞肺癌纵隔淋巴结转移风险模型的构建及预测效能的初步验证

目的:研究非小细胞肺癌（NSCLC）纵隔淋巴结转移的风险模型及预测效能。方法:回顾性分析2016年9月至2018年9月本院120例NSCLC患者临床资料,根据是否发生纵隔淋巴结转移将患者分为观察组（33例,发生纵隔淋巴结转移）和对照组（87例,未发生纵隔淋巴结转移）。采用Cox风险模型分析NSCLC发生纵隔淋巴结转移的危险因素,构建纵隔淋巴结转移的预测模型,并分析其诊断效能。结果:Cox风险模型分析显示肿瘤分化程度、SUVmax及脉管浸润是NSCLC纵隔淋巴结转移的高危因素（P＜0.05）。PI指数方程=0.516X1+0.496X2+0.638X3（X1=分化程度,X2=SUVmax,X3=脉管浸润）。ROC分析结果显示PI指数方程判断纵隔淋巴结转移的AUC为0.812（s=0.042,95%CI=0.730~0.894,P=0.000）,敏感度为0.758,特异度为0.747,对应PI值为1.154。结论:肿瘤分化程度、SUVmax及脉管浸润是NSCLC患者发生纵隔淋巴结转移的独立危险因素,据此构建风险模型有助于提高预测的准确性。     

Positron emission tomography is not useful in detecting metastasis in the sentinel lymph node in patients with primary malignant melanoma stage I and II

The most powerful predictor for recurrence and survival in patients with primary malignant melanoma is the presence or absence of lymph node metastases. In the present study, 18-fluoro-2-deoxyglucose positron emission tomography (FDG-PET) findings were compared with histopathological results of sentinel lymph node biopsy (SNB). The purpose was to determine the value of FDG-PET in predicting regional lymph node involvement in patients with primary malignant melanoma stage I and II. Forty-eight consecutive patients with primary cutaneous melanoma stage I (Breslow thickness > 1 mm) and II underwent FDG-PET scans, preoperative lymphoscintigraphy, and SNB. The FDG-PET and SNB results were interpreted independently of each other and then compared. Of the 48 patients included in the study, eight (16.7%) had a positive SNB. PET was positive in only one patient with a positive SNB, yielding a sensitivity of 13%. All other positive sentinel nodes could not be detected by metabolic FDG-PET imaging. Our study revealed that FDG-PET is obviously not an adequate screening test for subclinical and sonographically inconspicuous lymph node metastases in patients with malignant melanoma stage I and II. The low sensitivity is probably due to the small size of metastatic deposits in sentinel nodes. Therefore, SNB remains the technique of choice for evaluating the histological status of lymph node basins in patients with early-stage cutaneous melanoma.     

Accuracy of positron emission tomography in mediastinal node assessment in coal workers with lung cancer

The purpose of this study was to explore the accuracy of ¹⁸F-fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) in the assessment of mediastinal lymph node in coal workers who had non-small cell lung cancer. We retrospectively reviewed 42 retired coal workers who had lung cancer without distant metastasis, between May 2007 and May 2010. Regarding the mediastinal lymph nodes, when the standard uptake value was greater than 2.5, it was considered “malignancy positive.” After histological examination of the mediastinal lymph nodes, anthracotic and metastatic ones were detected. The results of PET/CT were analyzed to determine its accuracy. Of these 42 patients, PET/CT detected 47 positive mediastinal lymph nodes in 24 patients with a mean SUV maximum of 6.2 (2.6–13.8). One hundred and thirty-one mediastinal lymph node foci were dissected. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of FDG-PET/CT in detecting nodal metastases were 84% (16/19), 65% (15/23), 66% (16/24), 83% (15/18), and 74% (31/42) on a per-patient basis, respectively. Mediastinal node staging with FDG-PET/CT in coal workers is insufficient due to the high false-positive rates due to the presence of pneumoconiosis. In these patients, an invasive technique such as mediastinoscopy seems mandatory for confirmation of ipsilateral or contralateral mediastinal lymph node metastasis.     

Value of FDG-PET/CT Examinations in Different Cancers of Children, Focusing on Lymphomas

The aim of the study was to assess sensitivity and specificity of FDG-PET/CT in different forms of childhood cancer. We retrospectively evaluated the results dedicated of 162 FDG-PET/CT examinations of 86 children treated with: Hodgkin lymphoma (HL; n?=?31), non-Hodgkin lymphoma (NHL; n?=?30) and other high grade solid tumors (n?=?25). Patients were admitted and treated in two departments of pediatric hematology and oncology in Hungary. FDG-PET/CT was performed for staging (n?=?25) and for posttreatment evaluation (n?=?137). Imaging was performed in three FDG-PET/CT Laboratories, using dedicated PET/CT scanners. False positive results were defined as resolution or absence of disease progression over at least 1 year on FDG-PET/CT scans without any intervention. In some cases histopathological evaluation of suspicious lesions was performed. Fals negative results were defined as negative FDG-PET/CT results in case of active malignancy. Positive predictive values (PPV) and negative predictive values (NPV) were calculated. NPV was 100 %. The highest PPV was observed in high grade solid tumors (81 %), followed by HL (65 %) and NHL (61 %). There was a major difference of PPV in different histological types of HL (50 % in HL of mixed-cellularity subtype, 90 % in nodular sclerosing, and 100 % in lymphocyte-rich and lymphocyte depleted HL). We treated one patient with nodular lymphocyte predominant HL, who had 5 false positive FDG-PET/CT results. PPV of T- and B-lineage NHL were similar (60 % and 62 %, respectively). We observed an interesting difference of PPV in different stages of HL and NHL. In HL PPV was higher in early than in advanced disease forms: 66 % in stage II HL and 60 % in stage III HL, whereas there was an inverse relationship between PPV and disease stages in NHL 0 % in stage I and II patients, 67 % in stage III and 100 % in stage IV patients. PPV was lower in males (54 %) than in females (65 %). PPV were 64 % vs. 58 % in patients under vs. over 10 years of age. Negative FDG-PET/CT results during follow-up reliably predict the absence of malignancy. Positive FDG-PET/CT scan results in general have a low PPV. The relatively high PPV in patients with histologically proven high grade solid tumors, advanced stages of NHL and with nodular sclerosing, lymphocyte-rich and lymphocyte depleted subtypes of HL warrant a confirmation by biopsy, whereas the watch-and-wait approach can be used in other forms of childhood cancer patients with a positive FDG-PET/CT result in course of follow-up examinations.     

Association of Epstein-Barr virus genome with mixed cellularity and cellular phase nodular sclerosis Hodgkin's disease subtypes.

Association of Epstein-Barr virus (EBV) genome with Hodgkin's disease (HD) histological subtypes was investigated using the polymerase chain reaction (PCR). A highly significant association of EBV genome with the mixed cellularity (MC) subtype (10 positive out of 15 cases; 66%) was observed, suggesting a possible etiopathogenetic role of EBV in the induction of this subset. By contrast, a markedly lower frequency of association with EBV genome was found in nodular sclerosis (NS) (12 positive out of 46 cases; 26%) and in nodular lymphocytic predominance (NLP) (0 positive out of 5 cases) HD subtypes. In addition, in the NS series, the presence of EBV genome was mainly restricted to the 'cellular phase' NS subset. This finding strengthens the possibility, suggested by clinico-pathological features and survival rates, that 'cellular phase NS' is a disease more akin to MC than to typical NS HD.     

Improvement in preoperative staging of gastric adenocarcinoma with positron emission tomography

BACKGROUND: Positron emission tomography (PET) with 18- fluorodeoxyglucose (FDG) has been used to both detect and stage a variety of malignancies. The current study examined the value of PET for preoperative staging of gastric adenocarcinoma. METHODS: Sixty-eight patients (49 males and 19 females) with gastric adenocarcinoma, who were referred for preoperative FDG-PET scans, were enrolled in this study. The patients underwent spiral-computed tomography (CT) within 1 week of referral. The final diagnosis in all patients was made by histologic and surgical findings. For quantitative PET analysis, the regional tumor FDG uptake was measured by the standardized uptake value (SUV). RESULTS: For the primary tumor of a gastric adenocarcinoma, PET demonstrated an increased uptake in 64 of 68 patients (sensitivity, 94%), with a mean SUV of 7.0 (range, 0.9-27.7). A comparison of FDG uptake and clinicopathologic features showed significant association between FDG uptake and macroscopic type, tumor size, lymph node metastasis, histologic type, and TNM stage. The PET scan had a similar accuracy with that of CT for diagnosing local and distant lymph node metastases as well as peritoneal status. In assessing local lymph node status, however, PET had a higher specificity than CT (92% vs. 62%, P = 0.000). Moreover, PET had additional diagnostic value in 10 (15%) of 68 patients by upstaging 4 (6%) and downstaging 6 (9%) patients. PET combined with CT was more accurate for preoperative staging than either modality alone (66% vs. 51%, 66% vs. 47%, respectively; P = 0.002). CONCLUSIONS: FDG-PET improves the preoperative TNM staging of gastric adenocarcinoma. Based on its superior specificity, FDG-PET can facilitate the selection of patients for a curative resection by confirming a nodal status identified by CT.