Long-term outcomes of cervical cancer patients with complete metabolic response after definitive chemoradiotherapy.

OBJECTIVE: We investigated the importance of metabolic parameters measured with 18F-fluorodeoxyglucose positron-emission tomography integrated with computed tomography (FDG-PET/CT) for predicting progression-free survival (PFS) and overall survival (OS) in cervical cancer with complete metabolic response (CMR) after chemoradiotherapy (ChRT). METHODS: The clinical data and PET parameters including standardized uptake value (SUV), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of 122 patients having CMR in post-treatment 18F-FDG-PET/CT delivered a median of 3.9 months after ChRT completion were analyzed. RESULTS: With a median follow-up of 8.4 years, 55 patients (45%) presented with disease a median of 19.7 months after ChRT. For SUVp, MTVp, TLGp, SUVln, MTVln, and TLGp, the cut-off values for OS determined by receiver operating curve analysis were 15.8, 48.7 cm³, 552.3, 8.7, 7.0 cm³, respectively. All metabolic PET parameters were significant prognostic factors for OS and PFS in univariate analysis. International Federation of Gynecology and Obstetrics (FIGO) stage was predictive of both OS and PFS, while pelvic and/or para-aortic lymph node metastasis were predictive of OS only. In multivariate analysis, FIGO stage ≥IIB, MTVp ≥49.8 cm³, and TLGp ≥597.4 were predictive of worse OS. Advanced stage, presence of lymph node metastasis, higher TLGp, and larger MTVln were significant factors for poor PFS rates. CONCLUSION: We found that advanced stage and higher TLGp values were significant predictors for poor survival and higher progression rates. Volumetric PET parameters could be used to predict treatment outcomes in patients with CMR after definitive ChRT.

18F-FDG PET/CT Imaging in an Unusual Case of Cutaneous Melanoma Arising From Congenital Melanocytic Nevus in a Two-year-old Girl

Childhood malignant melanoma (MM) is extremely uncommon. We report an unusual case of cutaneous melanoma that developed from a medium-sized congenital melanocytic nevus (CMN) in a two-year-old girl. The patient had a history of CMN on the right hip, and she presented with a new ulcerative area with irregular borders and bleeding on CMN. Histopathological examination of the nevus revealed a MM. 18Florfluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography was performed for metastatic evaluation. The scan demonstrated metastatic increased 18F-FDG uptake in the right external iliac and inguinal lymph nodes.

The effect of androgen deprivation therapy on 68Ga-PSMA tracer uptake in non-metastatic prostate cancer patients.

PURPOSE: To evaluate the effect of neoadjuvant androgen deprivation treatment (ADT) on prostate-specific membrane antigen (PSMA) tracer uptake demonstrated in 68Ga-PSMA-positron emission tomography (PET/CT) in non-metastatic hormone-naïve prostate cancer (PC) patients. MATERIALS AND METHODS: The clinical data of 108 PC patients who received neoadjuvant ADT were retrospectively analyzed. All patients had a baseline 68Ga-PSMA-PET/CT scan, and a second scan was delivered median of 2.9 months after the initiation of ADT. The maximum standardized uptake value (SUVmax) of primary tumor (SUVp) and metastatic lymph nodes (SUVln) as well as PSA response were assessed between pre- and post-ADT 68Ga-PSMA-PET/CT scans. RESULTS: There were significant decreases in posttreatment serum PSA, SUVp, and SUVln. A decrease in SUVp was seen in 91 patients (84%) with a median value of 66% (range, 5-100%), while 17 patients (16%) had no change in or an increase in PSMA tracer uptake with a median value of 24% (range, 0-198%). Patients with Gleason score (GS) of 7 had significantly higher metabolic response rates compared to other patients. The disease progression was significantly higher only in patients with GS > 7 disease compared to GS 7 disease. The PSA response to ADT was the lowest in patients with ISUP high-grade tumors. A total of 16 patients (15%) had progressive disease, and in 9 patients (8%), radiotherapy decisions were modified according to posttreatment 68Ga-PSMA-PET/CT scans. CONCLUSIONS: The current study includes the largest number of patients analyzed to date and demonstrates that ADT causes a significant decrease in serum PSA values and SUVp and SUVln. The authors demonstrate that 68Ga-PSMA-PET/CT may be used as a quantitative imaging modality after neoadjuvant ADT in hormone-naïve non-metastatic PC patients.

Is PET/CT Necessary in the Management of Early Breast Cancer?

PURPOSE: Advanced imaging methods in early breast cancers are not recommended before surgery. In contrast to the accepted guidelines, some recent studies have shown some benefits with the use of PET/CT in early-stage breast cancer. In this study, we aimed to document the efficacy of PET/CT in detection of distant metastasis as well as other primary cancers. PATIENTS AND METHODS: In this retrospective study, we reviewed the records of all women patients diagnosed with early breast cancer between March 2012 and December 2014. Besides demographics, we recorded the clinical TNM stage, histology of the tumor, and hormone receptor status. As PET/CT imaging is a routine procedure in our center for early breast cancer, tumor size, lymph node status, distant metastasis, and possible other primary malignancies detected by PET/CT were also recorded. RESULTS: Of the 419 women included in the study, 24.8% were clinically staged as stage I while the rest were stage II. Distant metastases were detected in 42 patients (10%). The yield of PET/CT in detecting metastasis was significant in stage II patients compared with stage I patients (12.4% vs 2.9%). In subgroup analysis of stage II patients, the performance of PET/CT in detecting metastasis was still evident in stage IIA patients (9.5%). In logistic regression analysis of the significant and near-significant factors (as detected by univariate analysis) effecting PET/CT detected distant metastasis, only nodal status (P = 0.053) was found to be significant. CONCLUSIONS: We suggest the use of PET/CT in investigating metastasis in axilla positive and clinically stage II early breast cancer patients.

Choroidal Metastasis of Papillary Thyroid Carcinoma Demonstrated on SPECT-CT.

We report a 68-year-old woman with papillary thyroid carcinoma metastasizing to choroid. The choroid metastasis was diagnosed with SPECT-CT and then was treated with high-dose radioactive iodine therapy.

A Case of a Man With Isolated Breast Metastasis From Lung Adenocarcinoma Incidentally Detected by FDG PET/CT.

Breast metastases from an extramammary primary tumor are very rare, particularly in men. In this study, we present a case of a 74-year-old man with isolated breast metastasis from lung adenocarcinoma as an incidental finding on PET/CT and diagnosed concomitantly with the primary tumor. Detection of isolated incidental metastatic lesions in the breast on PET/CT imaging has a significant clinical impact on patients with known malignant disease due to change of disease stage, management, and also treatment method.

Venous thrombosis of sarcoidosis as an unusual incidental finding on 18F-fluorodeoxyglucose positron emission tomography/computed tomography.

Sarcoidosis is defined as a multisystem granulomatous disorder of unknown cause. Venous thrombosis (VT) in the sarcoidosis is rare. The routine use of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) has resulted in clinicians detecting many incidental findings, which have proven to be clinically significant such as thrombosis. Here, we present a case with VT of sarcoidosis in the inferior vena cava and portal vein as an unusual incidental finding on 18F-FDG PET/CT.

Focal 99mTc-DMSA Uptake in Lung Parenchyma Without Structural Alterations on SPECT/CT.

Static renal scintigraphy with Tc-DMSA is commonly used for the evaluation of renal morphology and function. Extrarenal uptake of Tc-DMSA is a rare finding described previously on sites such as bone metastasis, hemangioma, and splenic amyloidosis. We report a case with Tc-DMSA activity in the lungs.

Prognostic value of 18F-fluorodeoxyglucose uptake in pelvic lymph nodes in patients with cervical cancer treated with definitive chemoradiotherapy.

PURPOSE: To evaluate the prognostic significance of the maximum standardized uptake (SUVmax) value for pelvic lymph nodes in patients with cervical cancer and its impact on treatment response, disease control, and survival. METHODS: Ninety-three patients with pelvic or para-aortic metastasis detected by PET/CT and treated with definitive chemoradiotherapy were evaluated. The impact of pelvic lymph node SUVmax on prognostic factors and treatment outcomes was assessed. RESULTS: The size and SUVmax of pelvic lymph nodes were significantly correlated (r=0.859; p<0.001). Patients with pelvic and para-aortic lymph node metastases had significantly higher SUVmax values for both primary tumor (23.4±9.2 vs. 18.5±7.3; p=0.01) and pelvic lymph nodes (11.4±4.6 vs. 7.4±3.8; p=0.001). Patients with pelvic lymph node SUVmax≥7.5 had significantly higher primary tumor SUVmax, larger pelvic lymph nodes, higher rates of para-aortic lymph node metastasis, and lower post-therapy complete response rates. Overall survival (OS) and disease-free survival (DFS) rates were significantly higher in patients with SUVmax<7.5 compared to patients with SUVmax≥7.5. In a multivariate analysis, pelvic lymph node SUVmax and post-therapy metabolic response were significant prognostic factors for both OS and DFS for all patients, but no significant prognostic factors were found in pelvic lymph node metastasis only. CONCLUSIONS: Patients with highly FDG-avid pelvic lymph nodes have a higher risk of disease recurrence with worse survival. Identification of these patients may assist in the evaluation of the clinical benefits of additional treatments.

Elastofibroma dorsi incidentally detected by (18)F-FDG PET/CT imaging.

OBJECTIVE: Elastofibroma dorsi (ED) is a rare pseudotumor of the soft tissues that can also show 18F-fluorodeoxyglucose ((18)F-FDG) uptake on positron emission tomography combined with computed tomography (PET/CT) imaging. The aim of this retrospectively study was to describe the metabolic characteristics of ED incidentally detected by (18)F-FDG PET/CT imaging. MATERIALS AND METHODS: Between November 2009 and August 2013 at our institution, 10,350 consecutive PET/CT examinations were retrospectively investigated. In 176 of these patients, ED was recorded as an incidental finding. Fifty-five of 176 patients also had follow-up scans after chemoradiotherapy. A total of 231 scans with ED in 176 patients were identified. To determine the metabolic activity of ED, the maximum standardized uptake value (SUVmax) was calculated semiquantitatively. For measurement size of ED, the longest axis of transaxial CT images was used. Seven of the 176 patients underwent surgery due to suspected metastases and/or invasion of primary malignancy and/or symptoms or incidental during surgery. RESULTS: The prevalence of ED in our series was 1.7%. The lesions were located in the subscapular region in all patients, except in one case with a lesion in the infrascapular region. A total of 419 ED lesions in 231 scan of 176 patients were evaluated. Mean ± SD SUVmax and long axis values for these 419 lesions were 2.31 ± 0.61 (range 1.0-4.30) and 56.78 ± 17.01 mm (range 19-112 mm), respectively. Of these 176 patients, 141 (80.1%) had bilateral lesions and 35 (19.9%) had unilateral lesions. There were statistically significant differences in the SUVmax and long axis values between the right and left side in the bilateral lesions (p = 0.001). No significant differences in the SUVmax and long axis values of the lesion were found between pre- and posttreatment in the patients with follow-up scans. CONCLUSION: Elastofibroma dorsi located in the scapular region is usually bilateral, asymmetric and with mild or moderate metabolic activity on PET/CT imaging. In addition, the metabolic activity and size of ED remained stable after chemoradiotherapy. Awareness of these metabolic characteristics of ED is important for preventing misinterpretation during (18)F-FDG PET/CT studies.

Demonstration of cerebrospinal fluid leakage on radionuclide cisternography by SPECT/CT.

We report a case of a 37-year-old woman with severe headache provoked by postural changes who was referred to the nuclear medicine department for radionuclide cisternography to demonstrate suspected cerebrospinal fluid leakage. There was an increased uptake laterally on the left paraspinal region of upper thoracal spine and posteriorly on the upper cervical region. Fused SPECT/CT images located the exact leakage site as at the first costovertebral junction level on the left side laterally and on the posterior region of the first and second cervical spine. The treatment with epidural blood patch was successful.

Simultaneous occurrence of medullary and differentiated thyroid carcinomas. Report of 4 cases and brief review of the literature.

Simultaneous occurrence of medullary thyroid carcinoma (MTC) and papillary thyroid carcinoma (PTC) in a single patient is an unusual event. The incidence, cell origin, histopathology features and prognosis of these two carcinomas are considered completely different. The aim of this retrospective study was to describe clinical, pathologic characteristics and the prevalence of diagnosing such patients in our clinic. Between October 2003 and December 2013, 1.420 consecutive patients diagnosed by histology as having differentiated thyroid carcinoma (DTC) and treated with radioactive iodide (RAI) were retrospectively investigated. Of these, 4 patients were diagnosed by histology as having simultaneous MTC and PTC. The clinical and pathology characteristics of these patients are described. The prevalence of simultaneous MTC and PTC of these 4 patients in our clinic was 0.28% of all patients with DTC. The age of the 4 patients ranged from 44 to 63 years and were three females and one male. These patients are currently alive without disease from either of the two types of cancer. In two of these patients, MTC was located in the left and PTC in the right thyroid lobe. One patient had MTC in the right lobe and PTC in both lobes. The remaining patient had both cancers in the left lobe as a mixed tumor. We are able to present the pathology of only 2 of these 4 patients. In these 2 patients MTC was located in the left and PTC in the right thyroid lobe, one of them was female and the other was male, aged 44 and 49, respectively. In conclusion, our results suggested that simultaneous occurrence of MTC and PTC had a prevalence in our clinic of 0.28% among 1420 consecutive patients with DTC or 0.14%, if only the 2 patients in whom we are able to present their pathology slides are considered. Our cases suggest that these two tumors are usually independent and coincidental events in every patient.

Treatment outcomes of patients with cervical cancer with complete metabolic responses after definitive chemoradiotherapy.

PURPOSE: We sought to evaluate failure patterns and prognostic factors predictive of recurrences and survival in cervical cancer patients who are treated with definitive chemoradiotherapy (ChRT), who have a subsequent complete metabolic response (CMR) with (18) F-fluorodeoxyglucose positron-emission tomography (FDG-PET) after treatment. METHODS: The records of 152 cervical cancer patients who were treated with definitive chemoradiotherapy were evaluated. All patients underwent pre-treatment positron emission tomography (PET-CT), and post-treatment PET-CT was performed within a median of 3.9 months (range, 3.0-9.8 months) after the completion of ChRT. The prognoses of partial response/progressive disease (PR/PD) cases (30 patients, 18 %) and CMR cases (122 patients, %82) were evaluated. Univariate and multivariate analysis effecting the treatment outcome was performed in CMR cases. RESULTS: The median follow-ups for all patients and surviving patients were 28.7 (range, 3.3-78.7 months) and 33.2 months (range, 6.23-78.7 months), respectively. Four-year overall survival (OS) rate was significantly better in patients with CMR compared to patients with PR/PD (66.9 % vs. 12.4 %, p < 0.001, respectively). Patients with PR/PD had higher maximum standardized uptake value (SUVmax) of primary cervical tumor (26.4 ± 10.1 vs. 15.9 ± 6.3; p < 0.001) and larger tumor (6.4 cm ± 2.3 cm vs. 5.0 cm ± 1.4 cm; p < 0.001) compared to patients with CMR. Of the 122 patients with post-treatment CMRs, 25 (21 %) developed local, locoregional, or distant failure. In univariate analysis, tumor size ≥ 5 cm, 'International Federation of Obstetricians and Gynecologists' (FIGO) stage ≥ IIB, and pelvic and/or para-aortic lymph node metastasis were predictive of both overall survival (OS) and disease-free survival (DFS), while histology was predictive of only OS. In multivariate analysis, tumor size, stage and lymph node metastasis were predictive of OS and DFS. CONCLUSION: Although CMR is associated with better outcomes, relapses remain problematic, especially in patients with bulky tumors (≥ 5 cm), extensive stage (≥ IIB) or pelvic and/or para-aortic lymph node metastasis. These findings could support the need for more aggressive treatment or adjuvant chemotherapy regimens.

FDG-PET/CT-based restaging may alter initial management decisions and clinical outcomes in patients with locally advanced pancreatic carcinoma planned to undergo chemoradiotherapy.

The impact of [(18)F]fluorodeoxyglucose-positron emission tomography (PET)/computed tomography (CT) restaging on management decisions and outcomes in patients with locally advanced pancreatic carcinoma (LAPC) scheduled for concurrent chemoradiotherapy (CRT) is examined. Seventy-one consecutive patients with conventionally staged LAPC were restaged with PET/CT before CRT, and were categorized into non-metastatic (M0) and metastatic (M1) groups. M0 patients received 50.4 Gy CRT with 5-fluorouracil followed by maintenance gemcitabine, whereas M1 patients received chemotherapy immediately or after palliative radiotherapy. In 19 patients (26.8%), PET/CT restaging showed distant metastases not detected by conventional staging. PET/CT restaging of M0 patients showed additional regional lymph nodes in 3 patients and tumors larger than CT-defined borders in 4. PET/CT therefore altered or revised initial management decisions in 26 (36.6%) patients. At median follow-up times of 11.3, 14.5, and 6.2 months for the entire cohort and the M0 and M1 cohorts, respectively, median overall survival was 16.1, 11.4, and 6.2 months, respectively; median locoregional progression-free survival was 9.9, 7.8, and 3.4 months, respectively; and median progression-free survival was 7.4, 5.1, and 2.5 months, respectively (P < 0.05 each). These findings suggest that PET/CT-based restaging may help select patients suitable for CRT, sparing those with metastases from futile radical protocols, and increasing the accuracy of estimated survival.

A case of inoperable malignant insulinoma with resistant hypoglycemia who experienced the most significant clinical improvement with everolimus.

Metastatic insulinomas may sometimes present with recurrent life-threatening hypoglycemia episodes. Such patients usually fail to respond to various therapeutic agents which causes constant dextrose infusion requirement. Herein, we present a resistant case of inoperable malignant insulinoma who was treated with many therapeutic agents and interventions including somatostatin analogues, Yttrium-90 radioembolization, everolimus, radiotherapy, and chemoembolization. Close blood sugar monitorization during these therapies showed the most favourable response with everolimus. Everolimus treatment resulted in rapid improvement of hypoglycemia episodes, letting us discontinue dextrose infusion and discharge the patient. However, experience with everolimus in such patients is still limited, and more precise data can be obtained with the increasing use of this agent for neuroendocrine tumours.

Comparison of standardized uptake values obtained from two- and three-dimensional modes of fluorine-18 fluorodeoxyglucose PET-CT in oncological cases.

PURPOSE: We investigated the usability of standardized uptake values (SUV) obtained from both two- and three-dimensional (2D and 3D) positron-emission tomography and computed tomography (PET-CT) imaging, and compared the images obtained from these techniques in terms of image quality, lesion detectability, and the presence of artifacts. MATERIALS AND METHODS: Image data from 100 patients, who had undergone two PET imagings obtained in 2D and 3D mode after a low dose CT, were evaluated prospectively. Subjective analysis of 2D and 3D images was performed by two readers evaluating the following criteria: overall image quality, detectability of each identified lesion, and the presence of artifacts. The lesions recognized by the readers were also analyzed quantitatively by measuring SUV values. RESULTS: There was a significant difference between the SUVs obtained in 2D and 3D modes. Regardless if the first scan was performed in 2D or 3D mode, the values obtained from 3D imaging were significantly lower than those obtained from 2D imaging (mean SUV(max) was 10.48±7.57 for 2D, and 9.66±6.93 for 3D, P < 0.001). Visual analysis did not reveal significant differences regarding lesion detectability between two modes. CONCLUSION: In oncological PET-CT applications, SUV values are significantly lower in 3D compared with 2D mode. Thus when serial scanning is needed to evaluate response to therapy in the same patient, the imaging modality should be taken into account and performed with the same method to avoid misinterpretation. Additionally, 3D PET-CT imaging can be used instead of 2D PET-CT due to its shorter scanning time without loss of lesion detectability.

18F-FDG uptake in diffuse peritoneal lymphomatosis.

A 38-year-old man presented with declining appetite and progressive abdominal distention. Abdominal ultrasonography revealed omental and bowel wall thickening. Histopathologic examination showed a high-grade lymphoblastic Burkitt-like B-cell lymphoma. 18F fluorodeoxyglucose positron emission tomography/computed tomography images showed diffusely increased metabolic activity in the thickened omentum, intestines, mesentery, and peritoneum (omental caking). Diffuse peritoneal and omental seeding are well-known forms of dissemination of metastatic carcinoma. However, omental and peritoneal lymphomatosis are rare manifestations of high-grade lymphomas. This uncommon case demonstrates usefulness of F-18 fluorodeoxyglucose positron emission tomography/computed tomography in omental and peritoneal involvement in lymphoma.

Predictive value of metabolic 18FDG-PET response on outcomes in patients with locally advanced pancreatic carcinoma treated with definitive concurrent chemoradiotherapy.

BACKGROUND: We aimed to study the predictive value of combined 18F-fluoro-deoxy-D-glucose positron emission tomography and computerized tomography (FDG-PET-CT), on outcomes in locally advanced pancreatic carcinoma (LAPC) patients treated with concurrent chemoradiotherapy (C-CRT). METHODS: Thirty-two unresectable LAPC patients received 50.4 Gy (1.8 Gy/fr) of RT and concurrent 5-FU followed by 4 to 6 cycles of gemcitabine consolidation. Response was evaluated by FDG-PET-CT at post-C-CRT 12-week. Patients were stratified into two groups according to the median difference between pre- and post-treatment maximum standard uptake values (SUVmax) as an indicator of response for comparative analysis. RESULTS: At a median follow-up of 16.1 months, 16 (50.0%) patients experienced local/regional failures, 6 of which were detected on the first follow-up FDG-PET-CT. There were no marginal or isolated regional failures. Median pre- and post-treatment SUVmax and median difference were 14.5, 3.9, and -63.7%, respectively. Median overall survival (OS), progression-free survival (PFS), and local-regional progression-free survival (LRPFS) were 14.5, 7.3, and 10.3 months, respectively. Median OS, PFS, and LRPFS for those with greater (N = 16) versus lesser (N = 16) SUVmax change were 17.0 versus 9.8 (p = 0.001), 8.4 versus 3.8 (p = 0.005), and 12.3 versus 6.9 months (p = 0.02), respectively. On multivariate analysis, SUVmax difference was predictive of OS, PFS, and LRPFS, independent of existing covariates. CONCLUSIONS: Significantly higher OS, PFS, and LRPFS in patients with greater SUVmax difference suggest that FDG-PET-CT-based metabolic response assessment is an independent predictor of clinical outcomes in LAPC patients treated with definitive C-CRT.

Myocardial perfusion SPECT and dobutamine stress tissue Doppler imaging in evaluation of patients with stable angina pectoris.

OBJECTIVE: To evaluate longitudinal function of ischemic and nonischemic myocardial tissue detected by Tc-99m MIBI single photon emission computed tomography (SPECT) prior to coronary revascularization in patients with stable angina pectoris. METHODS: We studied 24 consecutive patients (mean age 62+/-9 years; 5 women) with stable angina pectoris. All patients underwent myocardial perfusion SPECT. Tissue Doppler imaging (TDI) was performed to detect myocardial systolic velocities of anterior, inferior, septum and lateral walls at rest and peak dobutamine stress. RESULTS: A total of 96 segments were visualized with SPECT study. Maximum mean septal, lateral, anterior and inferior TDI systolic velocities were similar in ischemic and nonischemic segments (6.73+/-1.04 cm/sec, 6.93+/-1.34 cm/sec, respectively) at rest. At peak stress, maximum mean TDI systolic velocities were lower in the 37 ischemic segments (11.00+/-2.03 cm/sec) than 59 nonischemic segments (13.76+/-1.97 cm/sec, p = 0.001). Because we detected ischemia in whole group using both diagnostic tests, coronary angiography was decided. Critical coronary artery stenosis related to ischemic segments was detected and coronary revascularization decided. CONCLUSION: TDI with dobutamine stress can be used in patients with stable angina pectoris. In this study, we observed that quantitative data by TDI associated with SPECT showed an agreement for coronary revascularization.