Mehmet Reyhan

Preoperative evaluation of hyperparathyroidism: the role of dual-phase parathyroid scintigraphy and ultrasound imaging

ObjectiveThe aim of this study was to evaluate the efficacy of dual-phase 99mTc-methoxyisobutylnitrile (MIBI) parathyroid scintigraphy (PS) and ultrasound (US) in primary (pHPT) and secondary (sHPT) hyperparathyroidism.MethodsA total of 69 patients (mean age 47 ± 16; age range 14–79 years), including 19 patients with sHPT were enrolled in this study. Preoperative serum intact parathyroid hormone (iPTH) levels, calcium (Ca), phosphate (P), alkaline phosphatase, and 24-h urinary-free Ca measurements were obtained. Concomitant thyroid pathology was also recorded.ResultsHistopathology revealed 30 solitary adenomas and 71 hyperplastic glands in 55 patients. The remaining patients’ histopathology revealed normal parathyroid, thyroid, or lymph nodes. The sensitivities of MIBI and US in pHPT were 70% and 60%, respectively. It was 60% for both procedures in sHPT. The overall sensitivity of combined US + MIBI in pHPT and sHPT was 81% and 71%, respectively. The overall specificity of MIBI and US was 87% and 91%; positive predictive value (PPV) was 94% and 92%, respectively. MIBI and US identified the parathyroid pathology in 92% and 85% of patients in the non-concomitant thyroid disease group, and in 53% and 47% of patients in the concomitant thyroid disease group, respectively. The weight of the gland between primary and secondary hyperparathyroidism did not reveal a significant difference (P = 0.4). Significant differences were found with respect to age, PTH, Ca, and P levels between the pHPT and sHPT (P < 0.001). Intact PTH levels showed significant differences between MIBI positive and negative patients (P = 0.013), and also US positive and negative patients (P = 0.012). A significant negative correlation was found between iPTH and Ca at sHPT (P < 0.001).ConclusionsThe concomitancy of thyroid disease greatly influences scintigraphic and ultrasonographic detection of parathyroid pathology in pHPT and sHPT. The combination of MIBI and US appears promising for localizing parathyroid pathology in patients with both primary and secondary hyperparathyroidism. The concordance rate is high together with a lower chance of missing concomitant thyroid pathology, which might alter the surgical approach.

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

Objective We analyzed the correlation of 18F-fluorodeoxyglucose (FDG) uptake into primary tumors using the maximum standardized uptake value (SUVmax) and clinicopathological factors of disease. The impact of the pretreatment SUVmax of the primary tumor on survival was investigated. Materials and Methods The records of 149 patients with biopsy-proven cervical cancer treated with definitive chemoradiotherapy (ChRT) were reviewed. All patients underwent pretreatment FDG positron emission tomography with computed tomography, and posttherapy FDG positron emission tomography with computed tomography was performed within a median interval of 4.2 months (range, 3.0–11.2 months) after the completion of chemoradiotherapy. Results The mean SUVmax in patients with lymph node metastasis was significantly higher than that in patients without metastasis (19.7 ± 8.2 vs 16.4 ± 8.2, respectively; P = 0.01). A significant difference existed between tumor size (<4 vs ≥4 cm) and the primary tumor SUVmax (14.7 ± 6.6 vs 18.7 ± 8.5, respectively; P = 0.02). The primary tumor pretreatment SUVmax for patients with complete remission was significantly lower than that of patients with partial response or progressive disease (15.6 ± 5.7 vs 28.0 ± 9.9, respectively; P < 0.001). The relationship between primary tumor FDG uptake and survival was evaluated by the cutoff value determined by receiver operating characteristic curve analysis. The area under the curve was 0.901 (P < 0.001; 95% confidence interval, 0.848–0.954), and 15.6 was determined as the SUVmax cutoff value. The 4-year actuarial overall survival (OS) and disease-free survival for SUVmax of less than 15.6 compared with SUVmax of 15.6 or greater were 85% vs 34% (P < 0.001) and 80% vs 29%, respectively (P < 0.001). In multivariate analysis, age, SUVmax of 15.6 or greater, and lymph node metastasis were independent prognostic factors of OS, and International Federation of Gynecology and Obstetrics stage IIB or higher, SUVmax of 15.6 or greater, and lymph node metastasis were significant factors for disease-free survival. Conclusion The primary tumor pretreatment SUVmax is correlated with increased tumor size and lymph node involvement at diagnosis, how well the primary tumor responds to treatment, the likelihood of disease recurrence, and OS.

Prognostic value of gross tumor volume delineated by FDG-PET-CT based radiotherapy treatment planning in patients with locally advanced pancreatic cancer treated with chemoradiotherapy

BackgroundWe aimed to assess whether gross tumor volume (GTV) determined by fusion of contrast-enhanced computerized tomography (CT) and 18F-fluoro-deoxy-D-glucose positron emission tomography-CT (FDG-PET-CT) based radiotherapy planning could predict outcomes, namely overall survival (OS), local-regional progression-free survival (LRPFS), and progression-free survival (PFS) in cases with locally advanced pancreas cancer (LAPC) treated with definitive concurrent chemoradiotherapy.MethodsA total of 30 patients with histological proof of LAPC underwent 50.4 Gy (1.8 Gy/28 fractions) of radiotherapy concurrent with continuously infused 5-FU followed by 4 to 6 courses of maintenance gemcitabine. Target volume delineations were performed on FDG-PET-CT-based RTP. Patients were stratified into 2 groups: GTV lesser (GTVL) versus greater (GTVG) than cut off value determined by receiver operating characteristic (ROC) analysis, and compared in terms of OS, LRPFS and PFS.ResultsMedian GTV delineated according to the FDG-PET-CT data was 100.0 cm3. Cut off GTV value determined from ROC curves was 91.1 cm3. At a median follow up of 11.2 months, median OS, LRPFS and PFS for the entire population were 10.3, 7.8 and 5.7 months, respectively. Median OS, LRPFS and PFS for GTVL and GTVG cohorts were 16.3 vs. 9.5 (p = 0.005), 11.0 vs. 6.0 (p = 0.013), and 9.0 vs. 4.8 months (p = 0.008), respectively.ConclusionsThe superior OS, LRPFS and PFS observed in GTVL patients over GTVG ones suggests a potential for FDG-PET-CT-defined GTV size in predicting outcomes of LAPC patients treated with definitive C-CRT, which needs to be validated by further studies with larger cohorts.

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.

Isolated mediastinal lymph node false positivity of [18F]-fluorodeoxyglucose-positron emission tomography/computed tomography in patients with cervical cancer.

Objective This study aimed to evaluate the degree of mediastinal involvement in patients with cervical cancer with isolated mediastinal [18F]-fluorodeoxyglucose–positron emission tomography (FDG-PET) positivity as verified by histopathologic examination. Methods Two hundred twenty-eight patients with newly diagnosed cervical cancer and who underwent FDG-PET imaging were analyzed. Twenty-nine patients (17%) had disseminated disease detected with PET/computed tomography (CT). Only 10 patients (4%) had increased FDG uptake in mediastinal lymph nodes alone. Of the 10 patients with mediastinal disease, 2 refused surgical mediastinal lymph node biopsy and did not receive any treatment. Patients with suspected paratracheal or subcarinal lymph node metastasis detected on PET/CT underwent mediastinoscopy, and those with hilar metastasis had video-assisted mediastinal lymphadenectomy. Treatment was delivered according to final staging based on histopathologic confirmation of mediastinal lymph node involvement. Results The mean (SD) maximum standardized uptake values for primary cervical tumor and mediastinal lymph nodes were 19.7 (10.3) and 7.5 (1.6), respectively. Of 8 patients who underwent mediastinal lymph node confirmation, 6 (75%) were tumor free, demonstrating granulomatous changes, and were treated curatively. No patients had residual or recurrent disease at the primary site, and all but 1 were alive without disease. Two patients with confirmed mediastinal lymph node metastasis were treated palliatively and died between 9 and 11 months after diagnosis. Conclusions Positron emission tomography/CT is an important tool for lymphatic staging and evaluation of distant metastases in cervical cancer. However, PET/CT should be interpreted cautiously for isolated mediastinal involvement; surgical evaluation is required for accurate staging and appropriate treatment decisions to achieve better outcomes.

Gastroesophageal scintigraphy in children: a comparison of posterior and anterior imaging

The purpose of this study was to compare the posterior dynamic imaging with the anterior imaging in the evaluation of children with gastroesophageal reflux (GER). Sixty-eight children (26 female, 42 male; age range 4 months to 7 years, median 21 months) were studied. After 4-hour fasting, all the subjects underwent gastroesophageal scintigraphy. Synchronous dynamic imaging in the anterior and posterior projections was performed with the subject in the supine position with a dual-head gamma camera equipped with low-energy general-purpose collimators at a rate of 30 s/frame for 40 min. The anterior and posterior images were visually evaluated for the presence of gastroesophageal reflux by two nuclear medicine physicians. The anterior and posterior images were correlated by Pearson correlation analysis, and inter-observer variability was evaluated by paired t-test and kappa value. There was a good correlation between the two projections with r-values of 0.906–0.990. The inter-observer agreement for interpretation of the anterior and posterior imaging was excellent (k: 0.83). In conclusion, anterior and posterior dynamic imaging showed excellent correlation in detection of GER in children. Posterior imaging is superior to anterior imaging in that it is more comfortable, and it reduces motion artifacts, especially for infants and anxious children; thus, it may be preferred over anterior imaging.

Colon Adenocarcinoma and Solitary Tibia Metastasis: Rare Entity

IntroductionColorectal cancer is the third leading cause of cancer-related deaths in the world. Mostly, death occurs with complications of distant metastases.DiscussionEffective systemic chemotherapy regimen and resultant improved survival for patients are associated with an increased incidence of metastases at uncommon sites. Therefore, incidences of osseous metastases are rising at the last decade. Osseous metastases are mostly diffuse, along with visceral metastases.ConclusionMost common osseous metastatic sites are lumbal, sacral vertebrae, and pelvis region, probably because of colonic anatomical proximity to the paravertebral venous plexus. Herein, we report an uncommon case of isolated solitary tibia metastasis in the colorectal cancer patient and management of disease course.

The conditions for which the geometric mean method revealed a more accurate calculation of relative renal function in 99mTc-DMSA scintigraphy

Aims(1) To compare the results of calculating relative renal function (RRF) by using only posterior images (POST) with the geometric mean (GM) through both anterior and posterior imaging on dimercaptosuccinic acid (DMSA) scintigraphy. (2) To determine whether there was an age-related difference between them and whether some renal pathologies or asymmetrical renal function cause an error in the RRF calculation by using posterior images only. MethodsEight hundred and ninety-one DMSA scans were studied retrospectively. The patients were divided into five age groups: group I, ≤2 years; group II, >2 to ≤5 years; group III, >5 to ≤10 years; group IV, >10 to ≤18 years; and group V, >18 years. The RRF of the right kidney (RKF) was calculated from the POST and GM counts. The differences between RKFGM and RKFPOST were calculated in all the patients. ResultsAmong the 891 patients, nine had malrotated or malpositioned kidneys, 373 had renal pathologies of pyelonephritis, hydronephrosis, cortical scarring and atrophy, 247 had asymmetrically functioning kidneys and 509 had normal kidneys. When the patients were analysed according to different age groups, significant differences were found between all groups (P<0.05) except groups I–II and IV–V (P>0.05) with the F-test. The clinically meaningful RRF variance (≥5% difference between two methods) rate differed significantly between groups I, II and III, and groups IV and V (chi-squared test, P<0.05). In patients aged ≤10 years, a clinically meaningful RRF variance (≥5%) rate was significantly higher in the groups with pathological or asymmetrically low (≤40% RRF) functioning kidneys than in the groups without pathological or asymmetrically low functioning kidneys, respectively (P<0.05). ConclusionsAccording to our findings, the calculation of RRF using the GM method differs significantly from that using posterior images. Calculation of the GM can effectively correct the RRF measurement not in only adults, but also in the patient population ♯10 years of age. In addition, a significant correction can be made in patients aged ♯10 years who have a renal pathology or an asymmetrically low functioning kidney.

Diffuse splenic tc-99m mdp uptake in hypersplenic patient

A 52-year-old woman with nonspecific left leg pain was examined by Tc-99m methylene diphosphonate (MDP) bone scintigraphy. The patient had been a marble quarry worker for 10 years and had developed chronic congestive heart failure secondary to pneumoconiosis. Her hemoglobin analysis and hematologic findings were interpreted as being consistent with sickle cell beta+ thalassemia and also hypersplenism. Bone scintigraphy showed intense and diffuse MDP accumulation in the enlarged spleen without ultrasonographic or radiologic evidence of calcification.

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.