The clinical utility of FDG-PET/CT in follow up and restaging of breast cancer patients

Background

Early diagnosis and accurate staging of loco-regional and distant recurrence after treatment of breast cancer is decisive for further therapeutic planning. Our aim was to evaluate the role of FDG-PET/CT in the follow up and restaging of breast cancer patients.

Methods

We retrospectively evaluated 34 female patients with a history of breast cancer. Patients were referred for a PET/CT scan because of suspected recurrence (n = 15), whole body staging in already confirmed cases of recurrence (n = 5), follow up and reassurance in asymptomatic patients (n = 7), follow up after local ablative therapy of liver metastases (n = 5), follow up after treatment of bone metastases (n = 2). PET-CT findings were compared with the findings obtained by other imaging modalities, histopathology, together with clinical and imaging follow up for at least 6 months.

Results

The PET/CT was considered pathological in 21/34 patients. Incorrect interpretations of PET/CT images occurred in 3 patients (8.8%). PET/CT showed an overall diagnostic accuracy of 91.2% with a sensitivity of 90.5% and a specificity of 92.3%. The PPV and NPV were 95% and 85.7%, respectively.

Conclusion

FDG-PET/CT may play a substantial role in the restaging and follow up of patients with breast cancer showing high sensitivity and specificity.     

Postoperative restaging: PET/CT impact on diagnosis and management

Purpose

The goal of this study was to assess the value of combined PET/CT in the restaging of suspected recurrent cancer and its impact on further management planning of the patients.

Patients and methods

Fourty-two patients with suspected recurrence due to new clinical, biochemical and radiologic findings were prospectively evaluated. PET/CT results were compared with PET and CT data. A final diagnosis of recurrence was confirmed by biopsy or by further clinical and radiologic work-up.

Results

Thirty nine out of 42 patients had recurrence and or distant metastases in 108 malignant sites. For the site-based analysis PET/CT showed 100% sensitivity, 80% specificity, 98% PPV, 100% NPV and 98% accuracy compared with 100%, 50%, 94%, 100% and 95%, respectively, for PET, and 87%, 50%, 94%, 28% and 83%, respectively, for CT. For the patient-based analysis, PET/CT showed 100% sensitivity, 75% specificity, 97% PPV, 100% NPV and 98% accuracy compared with 100%, 50%, 92%, 100% and 93%, respectively for PET and 86%, 75%, 97%, 38% and 86%, respectively for CT. PET/CT results changed the management of 90% of patients.

Conclusion

PET/CT provides accurate restaging of suspected recurrent cancer with a significant clinical impact on further management planning.     

Integrated contrast-enhanced diagnostic whole-body PET/CT as a first-line restaging modality in patients with suspected metastatic recurrence of breast cancer

Objective(s)

Only few information exist about the diagnostic accuracy of PET/CT for restaging patients with metastatic recurrence of breast carcinoma. Therefore, our study hypothesis was to perform diagnostic contrast enhanced CT (ce-CT) and FDG-PET in a one-step investigation, to prove sensitivity of each modality and to determine whether diagnostic PET/CT adds information over PET or contrast enhanced CT alone for restaging of patients with suspected recurrence of breast cancer.

Methods

Fifty-two patients with suspected recurrence of breast cancer were included in our study. All of them were free of metastasis after the first line therapy. Indications for restaging were: Elevated tumor markers n = 32, clinical deterioration n = 16 and/or suspicious findings on other imaging studies n = 48. Integrated PET/CT was performed using contrast-enhanced diagnostic CT for attenuation correction.

Results

PET was correct in 44/52 patients (85%), ce-CT in 38/52 patients (73%) and PET/CT in 50/52 patients (96%). Sensitivity and specificity of lesion detection of PET, CT and PET/CT were 84%, 66% and 93%, and 100%, 92%, and 100%, respectively.

Discussion

PET/CT can improve staging and alter therapeutic options in patients suspected to have breast cancer recurrence and distant metastatic disease, primarily by demonstrating local or distant nodal involvement occult at other imaging studies. The added value of FDG-PET/CT over other diagnostic modalities is mainly expressed by the fact that a noninvasive whole-body evaluation is possible in a single examination.     

Whole-body FDG PET/CT is more accurate than conventional imaging for staging primary breast cancer patients

Purpose

This retrospective study aimed (1) to compare the diagnostic accuracy of whole-body FDG PET/CT for initial breast cancer staging with the accuracy of a conventional, multimodal imaging algorithm, and (2) to assess potential alteration in patient management based on the FDG PET/CT findings.

Methods

Patients with primary breast cancer (106 women, mean age 57?±?13?years) underwent whole-body FDG PET/CT and conventional imaging (X-ray mammography, MR mammography, chest plain radiography, bone scintigraphy and breast, axillary and liver ultrasonography). The diagnostic accuracies of FDG PET/CT and a conventional algorithm were compared. Diagnostic accuracy was assessed in terms of primary tumour detection rate, correct assessment of primary lesion focality, T stage and the detection rates for lymph node and distant metastases. Histopathology, imaging or clinical follow-up served as the standards of reference.

Results

FDG PET/CT was significantly more accurate for detecting axillary lymph node and distant metastases (p?=?0.0125 and p?Conclusion Full-dose, intravenous contrast-enhanced FDG PET/CT was more accurate than conventional imaging for initial breast cancer staging due to the higher detection rate of metastases and synchronous tumours, although the study had several limitations including a retrospective design, a possible selection bias and a relevant false-positive rate for the detection of axillary lymph node metastases. FDG PET/CT resulted in a change of treatment in a substantial proportion of patients.     

F-FDG-PET/CT in staging,restaging, and treatment response assessment of male breast cancer

Purpose

Male breast cancer (BC) is a rare disease, with patterns different from those found in women. Most tumors are detected at more advanced stages than in women. The aim of this study was to analyze the performance of [18F]fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG-PET/CT) in staging, restaging, and therapy response assessment.

Methods

We performed a systematic analysis in the database of Saint-Louis Hospital to identify male patients with BC referred for PET/CT. ¹⁸F-FDG-PET/CT findings considered suspicious for malignancy were compared to biopsy results, further work-up and/or patient follow-up of at least 6 months. Performances of ¹⁸F-FDG-PET/CT were compared to that of conventional imaging (CI) using the McNemar test. The impact of PET/CT on management was evaluated.

Results

During 6 consecutive years, among 12,692 ¹⁸F-FDG-PET/CT oncology studies, 30 were performed in 15 men with BC: 7 examinations for initial staging, 11 for restaging, and 12 for response assessment. Tumors profile was ER+ and one had HER2 overexpression. PET/CT sensitivity, specificity, positive predictive value, negative predictive value and accuracy to detect distant metastases were 100%, 67%, 86%, 100% and 89%, respectively. PET/CT was more informative than CI in 40% of studies (p = 0.03; 95% confidence interval: 3.26 – 40%). Findings from ¹⁸F-FDG-PET/CT led to modification in the planned treatment in 13/30 cases (43%).

Conclusion

Although all the tumors were ER+, primary lesions and metastases were diagnosed with high sensitivity. ¹⁸F-FDG-PET/CT seems to be a powerful imaging method to perform staging, restaging and treatment response assessment in male patients with BC.     

The diagnostic usefulness of FDG-PET/CT in detecting tumor recurrence not evident in whole body I scan in differentiated thyroid carcinoma

Objective

Patients with differentiated thyroid carcinoma (DTC) have generally an encouraging prognosis, however, some patients develop an increasing level of serum thyroglobulin (Tg) without detection of a recurrent tumor using conventional imaging tools such as the iodine-131 whole-body scanning (I¹³¹ scan). The objective of our study was to evaluate the clinical significance of [F¹⁸]-FDG-PET/CT in detection of tumor recurrence or metastases, in comparison to conventional imaging such as the I¹³¹ scan.

Patients and methods

Between January 2013 and June 2013, [18F]-FDG-PET/CT examination was done for 12 DTC patients with elevated thyroglobulin levels and who did not show any pathological lesions when conventional imaging modalities were used. All involved patients had undergone total thyroidectomy, and who had been followed-up by whole body iodine scan [F¹⁸]-FDG PET/CT data were evaluated for detecting recurrent DTC lesions in study patients and compared with those of other radiological and/or cytological investigations.

Results

Five of 12 patients (41.6 %) showed pathological [F18]-FDG uptake in the absence of abnormal uptake in whole body iodine scan.

Conclusion

[F18]-FDG-PET/CT affords a valuable diagnostic method in detection of recurrence or metastasis in patients with DTC who are tumor-free on conventional imaging studies with high Tg levels.     

Low-dose non-enhanced CT versus full-dose contrast-enhanced CT in integrated PET/CT scans for diagnosing ovarian cancer recurrence

Objective

To evaluate low-dose non-enhanced CT (ldCT) and full-dose contrast-enhanced CT (ceCT) in integrated ¹⁸F-fluorodeoxyglucose (FDG)-PET/CT studies for restaging of ovarian cancer.

Materials and methods

One hundred and twenty women who had undergone treatment for ovarian cancer underwent a conventional PET/CT scans with ldCT, and then ceCT. Two observers interpreted and decided in consensus on the PET/ldCT and PET/ceCT images by a 3-point scale (N: negative, E: equivocal, P: positive) per patient and lesion site. Final diagnoses were obtained by histopathological examinations, or clinical follow-up for at least 6 months.

Results

Patient-based analysis showed that the sensitivity, specificity, and accuracy of PET/ceCT was 86.9% (40/46), 95.9% (71/74), and 92.5% (111/120), respectively, whereas those of PET/ldCT were 78.3% (36/46), 95.0% (70/74), and 88.3% (106/120), respectively. All sensitivity, specificity, and accuracy significantly differed between two methods (McNemar test, p < 0.0005, p = 0.023, and p < 0.0001, respectively). The scales of detecting 104 recurrent lesion sites were N:14, E:6, P:84 for PET/ceCT, and N:15, E:17, P:72 for PET/ldCT, respectively. Eleven equivocal and one negative regions by PET/ldCT were correctly interpreted as positive by PET/ceCT.

Conclusion

PET/ceCT is a more accurate imaging modality with higher confidence for assessing ovarian cancer recurrence than PET/ldCT.     

Prospective assessment of 18F-FDG PET/CT in detection of recurrent ovarian cancer

Objective

To assess the use of positron emission tomography (PET)/computed tomography (CT) in patients with suspected ovarian cancer recurrence and describe the distribution of metastasis.

Patients and methods

This study included (39) patients suspected to have recurrent ovarian malignancy. This suspicion was either clinically, radiologically or due to raised CA-125 levels. All patients underwent 18F-FDG PET/CT, surgery was performed within 8 weeks of imaging studies. Surgical and/or histopathological examinations were available in 31 patients, and clinical, radiological and CA 125 serum level follow up in 8 patients.

Results

The overall lesion-based sensitivity, specificity, and accuracy of PET/CT for revealing recurrent ovarian carcinoma were 90%, 98% and 97%, respectively. The patient – based sensitivity, specificity, and accuracy of PET/CT were 97%, 75% and 95%, respectively.

Conclusion

18F-FDG PET/CT is a useful tool for evaluating the recurrence of ovarian cancer after first-line therapy in patients with a high risk of relapse, equivocal radiologic findings, increased or normal levels of serum CA-125. It can more accurately diagnose and localize recurrence, hence decreasing the rate of second look surgery and changing treatment plan.     

Accuracy of 18F-FDG PET/CT in detection and restaging of recurrent ovarian cancer

Purpose

To estimate the accuracy of 18FDG PET/CT in detection of recurrent cancer ovary and to describe the localization of metastases for restaging.

Simulation of a MR-PET protocol for staging of head-and-neck cancer including Dixon MR for attenuation correction

Purpose

To simulate and optimize a MR protocol for squamous cell cancer of the head and neck (HNSCC) patients for potential future use in an integrated whole-body MR–PET scanner.

Materials and methods

On a clinical 3T scanner, which is the basis for a recently introduced fully integrated whole-body MR–PET, 20 patients with untreated HNSCC routinely staged with 18F-FDG PET/CT underwent a dedicated MR protocol for the neck. Moreover, a whole-body Dixon MR-sequence was applied, which is used for attenuation correction on a recently introduced hybrid MR–PET scanner. In a subset of patients volume-interpolated-breathhold (VIBE) T1w-sequences for lungs and liver were added. Total imaging time was analyzed for both groups. The quality of the delineation of the primary tumor (scale 0–3) and the presence or absence of lymph node metastases (scale 1–5) was evaluated for CT, MR, PET/CT and a combination of MR and PET to ensure that the MR–PET fusion does not cause a loss of diagnostic capability. PET was used to identify distant metastases. The PET dataset for simulated MR/PET was based on a segmentation of the CT data into 4 classes according to the approach of the Dixon MR-sequence for MR–PET. Standard of reference was histopathology in 19 cases. In one case no histopathological confirmation of a primary tumor could be achieved.

Results

Mean imaging time was 35:17 min (range: 31:08–42:42 min) for the protocol including sequences for local staging and attenuation correction and 44:17 min (range: 35:44–54:58) for the extended protocol. Although not statistically significant a combination of MR and PET performed better in the delineation of the primary tumor (mean 2.20) compared to CT (mean 1.40), MR (1.95) and PET/CT (2.15) especially in patients with dental implants. PET/CT and combining MR and PET performed slightly better than CT and MR for the assessment of lymph node metastases. Two patients with distant metastases were only identified by PET.

Conclusion

We established a potential MR-protocol to be used for HNSCC patients in a recently introduced MR–PET scanner. The proposed protocol can be performed in an acceptable time frame and did not lead to a loss of diagnostic capability compared to PET/CT.     

Value of Surveillance 18F-FDG PET/CT in Colorectal Cancer: Comparison with Conventional Imaging Studies

Purpose

To assess the value of PET/CT for detecting local or distant recurrence in patients who undergo surgery for colorectal cancer (CRC) and to compare the accuracy of PET/CT to that of conventional imaging studies (CIS).

Methods

Tumor surveillance PET/CT scans done between March 2005 and December 2009 of disease-free patients after surgery with or without adjuvant chemotherapy for CRC were retrospectively studied. CIS (serial enhanced CT from lung base to pelvis and plain chest radiograph) were performed within 1 month of PET/CT. We excluded patients with distant metastasis on initial staging, a known recurrent tumor, and a lack of follow-up imaging. The final diagnosis was based on at least 6 months of follow-up with colonoscopy, biopsy, and serial imaging studies in combination with carcinoembryonic antigen levels.

Results

A total of 262 PET/CT scans of 245 patients were included. Local and distant recurrences were detected in 27 cases (10.3%). On case-based analysis, the overall sensitivity, specificity, and accuracy were 100, 97.0, and 97.3% for PET/CT and 85.1, 97.0, and 95.8% for CIS, respectively. On lesion-based analysis, PET/CT detected more lesions compared to CIS in local recurrence and lung metastasis. PET/CT and CIS detected the same number of lesions in abdominal lymph nodes, hepatic metastasis, and peritoneal carcinomatosis. PET/CT detected two more metachronous tumors than did CIS in the lung and thyroid gland.

Conclusion

PET/CT detected more recurrences in patients who underwent surgery for CRC than did CIS and had the additional advantage of evaluating the entire body during a single scan.     

Evaluation of the efficiency of FDG PET/CT in detection and characterization of skeletal metastases

Background and purpose

Combined PET/CT using 18F-FDG is widely used in evaluation of various malignancies; in their initial staging and more efficiently in their follow up; hence, the importance of evaluation of its diagnostic role in the imaging of skeletal metastases. The purpose of this study is to evaluate precisely the efficiency of FDG PET/CT in detection and characterization of osseous metastatic lesions compared to isolated PET and CT in various malignancies.

Patients and methods

The study included 123 patients divided into seven groups of malignancies to whom PET/CT was done. In this study population, a detailed retrograde lesion based analysis was performed for a total of 1705 detected bone lesions on PET, CT and fused PET/CT images. Sensitivity, specificity, PPV and NPV of each modality were calculated. Semi-quantitative and ROC curve analysis of the lesions were performed to study the relationship between the lesion’s SUV and its corresponding morphologic pattern on CT and to set a reliable SUV_max cut-off value that can predict the presence of malignant lesion.

Results

The calculated fused PET/CT sensitivities and specificities in various malignancies ranged from 95.2% to 99.6% and 75% to 100%, respectively. The combined PET/CT has significantly improved the low CT sensitivity (especially in lymphoma) as well as both CT and PET specificities. Our ROC analysis suggested using SUV_max of 3 as a cut off value for malignant osseous lesions.

Conclusion

Fused PET/CT was highly efficient in evaluation of skeletal metastases with superior performance in: detection of early bone marrow infiltration not apparent on CT, resolution of metabolic activity before definite signs of complete healing on CT, detection of missed sclerotic metastases on PET due to their relatively low metabolic activity, detection of intra and extra osseous recurrence and differentiation of benign from malignant bone lesions.     

Computer tomography, magnetic resonance imaging, and positron emission tomography or positron emission tomography/computer tomography for detection of metastatic lymph nodes in patients with ovarian cancer: a meta-analysis

Objectives

To compare the diagnostic performances of computed tomography (CT), magnetic resonance (MR) imaging, and positron emission tomography (PET or PET/CT) for detection of metastatic lymph nodes in patients with ovarian cancer.

Methods

Relevant studies were identified with MEDLINE and EMBASE from January 1990 to July 2010. We estimated the weighted summary sensitivities, specificities, OR (odds ratio), and summary receiver operating characteristic (sROC) curves of each imaging technique and conducted pair-wise comparisons using the two-sample Z-test. Meta-regression, subgroup analysis, and funnel plots were also performed to explain the between-study heterogeneity.

Results

Eighteen eligible studies were included, with a total of 882 patients. PET or PET/CT was a more accurate modality (sensitivity, 73.2%; specificity, 96.7%; OR [odds ratio], 90.32). No significant difference was detected between CT (sensitivity, 42.6%; specificity, 95.0%; OR, 19.87) and MR imaging (sensitivity, 54.7%; specificity, 88.3%; OR, 12.38). Meta-regression analyses and subgroup analyses revealed no statistical difference. Funnel plots with marked asymmetry suggested a publication bias.

Conclusion

FDG-PET or FDG-PET/CT is more accurate than CT and MR imaging in the detection of lymph node metastasis in patients with ovarian cancer.     

Hybrid <Superscript>18</Superscript>F–FDG PET/MRI might improve locoregional staging of breast cancer patients prior to neoadjuvant chemotherapy

Purpose

Our purpose in this study was to assess the added clinical value of hybrid ¹⁸F–FDG-PET/MRI compared to conventional imaging for locoregional staging in breast cancer patients undergoing neoadjuvant chemotherapy (NAC).

Methods

In this prospective study, primary invasive cT2-4 N0 or cT1-4 N+ breast cancer patients undergoing NAC were included. A PET/MRI breast protocol was performed before treatment. MR images were evaluated by a breast radiologist, blinded for PET images. PET images were evaluated by a nuclear physician. Afterwards, a combined PET/MRI report was written. PET/MRI staging was compared to conventional imaging, i.e., mammography, ultrasound and MRI. The proportion of patients with a modified treatment plan based on PET/MRI findings was analyzed.

Results

A total of 40 patients was included. PET/MRI was of added clinical value in 20.0% (8/40) of patients, changing the treatment plan in 10% and confirming the malignancy of suspicious lesions on MRI in another 10%. In seven (17.5%) patients radiotherapy fields were extended because of additional or affirmative PET/MRI findings being lymph node metastases (n = 5) and sternal bone metastases (n = 2). In one (2.5%) patient radiotherapy fields were reduced because of fewer lymph node metastases on PET/MRI compared to conventional imaging. Interestingly, all treatment changes were based on differences in number of lymph nodes suspicious for metastasis or number of distant metastasis, whereas differences in intramammary tumor extent were not observed.

Conclusion

Prior to NAC, PET/MRI shows promising results for locoregional staging compared to conventional imaging, changing the treatment plan in 10% of patients and potentially replacing PET/CT or tissue sampling in another 10% of patients.

     

FDG PET/MR for lymph node staging in head and neck cancer

Objective

To assess the diagnostic value of PET/MR (positron emission tomography/magnetic resonance imaging) with FDG (18F-fluorodeoxyglucose) for lymph node staging in head and neck cancer.

Materials and methods

This prospective study was approved by the local ethics committee; all patients signed informed consent. Thirty-eight patients with squamous cell carcinoma of the head and neck region underwent a PET scan on a conventional scanner and a subsequent PET/MR on a whole-body hybrid system after a single intravenous injection of FDG. The accuracy of PET, MR and PET/MR for lymph node metastases were compared using receiver operating characteristic (ROC) analysis. Histology served as the reference standard.

Results

Metastatic disease was confirmed in 16 (42.1%) of 38 patients and 38 (9.7%) of 391 dissected lymph node levels. There were no significant differences between PET/MR, MR and PET and MR (p > 0.05) regarding accuracy for cervical metastatic disease. Based on lymph node levels, sensitivity and specificity for metastatic involvement were 65.8% and 97.2% for MR, 86.8% and 97.0% for PET and 89.5% and 95.2% for PET/MR.

Conclusions

In head and neck cancer, FDG PET/MR does not significantly improve accuracy for cervical lymph node metastases in comparison to MR or PET.     

Predictive role of post-treatment [18F]FDG PET/CT in patients with uterine cervical cancer

Objective

To evaluate the efficacy of post-treatment positron emission tomography (PET)/computed tomography (CT) for identification of tumor recurrence, and to determine whether [¹⁸F]fluorodeoxyglucose (FDG) uptake measured as the maximum standardized uptake value (SUV_max) has predictive role regarding survival in patients with uterine cervical cancer.

Methods

Medical records from 276 women with uterine cervical cancer who had post-treatment [¹⁸F]FDG PET/CT performed were retrospectively reviewed. Results of PET/CT scans were compared with histological or clinical examination.

Results

Ninety-five (34.4%) of the 276 patients had documented recurrence by either surgical biopsy or clinical and imaging follow-up. Median duration from treatment to PET/CT scan was 24 months (range, 6–307). The overall sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of post-treatment PET/CT were 94.7%, 87.8%, 80.4%, 97%, and 90.2%, respectively. The PET/CT scan modified both the diagnostic or treatment plan in 67 patients (24.3%). Patients were divided into two groups according to cut-off SUV_max established on the basis of ROC analysis (<5.25 vs. ≥5.25), and there was a significant difference in OS between groups (p = 0.001). In addition, the 5-year progression-free survival (PFS) and OS rates of patients with a negative PET/CT scan for recurrence were significantly better than those with a positive PET/CT (98.62% vs. 17.83%, p < 0.0001 for PFS, 99.31% vs. 85.38%, p = 0.0015 for OS).

Conclusion

Post-treatment PET/CT scan is a sensitive and accurate surveillance modality, and provides prognostic information in uterine cervical cancer. Furthermore, it may allow individualization of patient care.     

Prognostic evaluation of PET/CT in residual post-chemotherapy masses in patients with diffuse large B-cell lymphoma and its impact on survival

Aim of the work

To evaluate the prognostic value and accuracy of PET/CT in DLBCL patients with post-treatment CT-residual masses with concern in overall (OAS) and progression-free survival (PFS).

Materials and methods

We retrospectively studied 62 patients with DLBCL who had CT documented residual masses (CRu) after completion of chemotherapy.

Results

Forty-four patients with negative PET scan were free of relapse while 4 out of 18 patients with positive scan showed CR, the other 14 patients had developed relapse. PET attained a sensitivity of 100%, a specificity of 91%, a NPV of 100% and a PPV of 77.8% and an accuracy of 93.5%. The median OAS time was 33.59 months in patients with negative scan and 19.00 months in patients with positive scan with highly significant correlation (P value 0.0001) and the median PFS time was 29.53 months in patients with negative scan versus only 4.00 months in patients with positive scan with highly significant correlation (P value 0.0000).

Conclusion

PET/CT plays helpful part in evaluation of therapy response in DLBCL patients with CT residual mass and post-chemotherapy PET could be used as an accurate and good predictor of OAS and PFS.     

Opportunities for 2-[18F] Fluoro-2-Deoxy-D-Glucose PET/CT in Cervical-Vaginal Neuroendocrine Carcinoma: Case Series and Literature Review

Objective

Neuroendocrine cervical carcinoma is a rare subtype of cervical cancer. These tumors exhibit an aggressive behavior with early regional lymph node and distant metastases. The purpose of our study was to describe five cases of neuroendocrine cervical-vaginal carcinoma and to discuss the potential of the 2-[¹⁸F] fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) scan for the detection of this rare malignancy.

Materials and Methods

Five cases of cervical-vaginal neuroendocrine tumor were retrospectively collected, during a two year (from September 2009 to August 2011) period in our hospital. The clinical staging distributions were International Federation of Gynecology and Obstetrics (FIGO) stage IB2 (1 of 5), stage IIA (3 of 5) and stage IVA (1 of 5).

Results

Two cases (cases 1 and 4) were restaged after ¹⁸F-FDG PET/CT scan in the initial staging process. Post-treatment ¹⁸F-FDG PET/CT scans, in three patients, revealed positive findings for tumor recurrence or lymph node metastases. Two patients (cases 2 and 3) died of tumor within two years.

Conclusion

¹⁸F-FDG PET/CT scan is a useful tool in cervical-vaginal neuroendocrine tumor. In its initial staging, the ¹⁸F-FDG PET/CT scan may help assess the possible nodal involvement or early hematogeneous spreading. We can also use the ¹⁸F-FDG PET/CT to detect local recurrence and to evaluate the treatment response after clinical manipulation.     

PET/CT scanning guided intensity-modulated radiotherapy in treatment of recurrent ovarian cancer

Objective

This study was undertaken to evaluate the clinical contribution of positron emission tomography using ¹⁸F-fluorodeoxyglucose and integrated computer tomography (FDG-PET/CT) guided intensity-modulated radiotherapy (IMRT) for treatment of recurrent ovarian cancer.

Materials and methods

Fifty-eight patients with recurrent ovarian cancer from 2003 to 2008 were retrospectively studied. In these patients, 28 received PET/CT guided IMRT (PET/CT–IMRT group), and 30 received CT guided IMRT (CT–IMRT group). Treatment plans, tumor response, toxicities and survival were evaluated.

Results

Changes in GTV delineation were found in 10 (35.7%) patients based on PET–CT information compared with CT data, due to the incorporation of additional lymph node metastases and extension of the metastasis tumor. PET/CT guided IMRT improved tumor response compared to CT–IMRT group (CR: 64.3% vs. 46.7%, P = 0.021; PR: 25.0% vs. 13.3%, P = 0.036). The 3-year overall survival was significantly higher in the PET–CT/IMRT group than control (34.1% vs. 13.2%, P = 0.014).

Conclusions

PET/CT guided IMRT in recurrent ovarian cancer patients improved the delineation of GTV and reduce the likelihood of geographic misses and therefore improve the clinical outcome.     

Staging accuracy of pancreatic cancer: Comparison between non-contrast-enhanced and contrast-enhanced PET/CT

Purpose

Our aim was to clarify the diagnostic impact of contrast-enhanced (CE) ¹⁸F-fluorodeoxyglucose (FDG)–positron emission tomography (PET)/computed tomography (CT) for staging of pancreatic cancer compared to non-CE PET/CT.

Method and materials

Between April 2006 and November 2009, a total of 95 patients (age range, 36–83 years [mean age, 67]) with primary pancreatic cancer underwent ¹⁸F-FDG PET/CT examinations. Diagnostic accuracy was compared between non-CE PET/CT and CE PET/CT. Images were analyzed visually and quantitatively by two blinded reviewers. Reference standard was histological examination in 48 patients (51%) and/or confirmation of an obvious progression in number and/or size of the lesions on follow-up CT examinations in 47 patients (49%).

Results

For T-staging, invasion of duodenum (n = 20, 21%), mesentery (n = 12, 13%), and retroperitoneum (n = 13, 14%) was correctly diagnosed by both modalities. The ROC analyses revealed that the Az values of celiac artery (CA), common hepatic artery (CHA), splenic artery (SV), and superior mesenteric vein (SMV) invasion were significantly higher in the CE PET/CT group for both readers. Nodal metastasis was correctly diagnosed by CE PET/CT in 38 patients (88%) and by non-CE PET/CT in 45 patients (87%). Diagnostic accuracies of nodal metastasis in two modalities were similar. Using CE PET/CT, distant metastasis, scalene node metastasis, and peritoneal dissemination were correctly assigned in 39 patients (91%), while interpretation based on non-CE PET/CT revealed distant metastasis, scalene node metastasis, and peritoneal dissemination in 42 patients (81%). Diagnostic accuracy of distant metastasis, scalene node metastasis, and peritoneal dissemination with CE PET/CT was significantly higher than that of non-CE PET/CT (p < 0.05).

Conclusion

CE PET/CT allows a more precise assessment of distant metastasis, scalene node metastasis, and peritoneal dissemination in patients with pancreatic cancer.