Semra Ince

Clinical impact of 18F-FDG PET/CT on initial staging and therapy planning for breast cancer

The purpose of this study was to determine the clinical significance of 18F-FDG PET/CT on initial staging and therapy planning in patients with invasive breast cancer. One hundred and forty-one consecutive, biopsy proven preoperative and 195 postoperative high-risk breast cancer patients who were referred for PET/CT for initial staging were included in this retrospective study. The clinical stage had been determined by conventional imaging modalities prior to the PET/CT scan. Of the 141 examined preoperative patients, 19 had clinical stage I (T1N0), 51 had stage IIA (12 T2N0 and 39 T1N1), 49 had stage IIB (2 T3N0 and 47 T2N1), 12 had stage IIIA (11 T3N1, 1 T2N2), 2 had stage IIIB (2 T4N1) and 8 had stage IV. PET/CT modified the staging for 26% of stage I patients, 29% of stage IIA patients, 46% of stage IIB patients, 58% of stage IIIA patients and 100% of stage IIIB patients. PET/CT scans detected extra-axillary regional lymph nodes in 14 (9.9%) patients and distant metastasis in 41 (29%) patients. PET/CT scans detected multifocal lesions in 30 (21%) patients, multicentric lesions in 21 (14%) patients and malign foci in the contralateral breast (bilateral breast cancer) confirmed by biopsy in 5 (3.5%) patients. Of the examined 195 postoperative patients PET/CT detected axillary lymph nodes in 22 (11%) patients, extra-axillary regional lymph nodes in 21 (10%) patients and distant metastasis in 24 (12%) patients. PET/CT findings altered plans for radiotherapy in 22 (11%) patients and chemotherapy was adapted to the meta-static diseases in 24 (12%) patients. PET/CT was revealed to be superior to conventional imaging modalities for the detection of extra-axillary regional metastatic lymph nodes and distant metastases. These features make PET/CT an essential imaging modality for the primary staging of invasive breast cancer, particularly in patients with clinical stages II and III.

Prognosis estimation under the light of metabolic tumor parameters on initial FDG-PET/CT in patients with primary extranodal lymphoma

Abstract Background Non-Hodgkin’s lymphomas arising from the tissues other than primary lymphatic organs are named primary extranodal lymphoma. Most of the studies evaluated metabolic tumor parameters in different organs and histopathologic variants of this disease generally for treatment response. We aimed to evaluate the prognostic value of metabolic tumor parameters derived from initial FDG-PET/CT in patients with a medley of primary extranodal lymphoma in this study. Patients and methods There were 67 patients with primary extranodal lymphoma for whom FDG-PET/CT was requested for primary staging. Quantitative PET/CT parameters: maximum standardized uptake value (SUVmax), average standardized uptake value (SUVmean), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were used to estimate disease-free survival and overall survival. Results SUVmean, MTV and TLG were found statistically significant after multivariate analysis. SUVmean remained significant after ROC curve analysis. Sensitivity and specificity were calculated as 88% and 64%, respectively, when the cut-off value of SUVmean was chosen as 5.15. After the investigation of primary presentation sites and histo-pathological variants according to recurrence, there is no difference amongst the variants. Primary site of extranodal lymphomas however, is statistically important (p = 0.014). Testis and central nervous system lymphomas have higher recurrence rate (62.5%, 73%, respectively). Conclusions High SUVmean, MTV and TLG values obtained from primary staging FDG-PET/CT are potential risk factors for both disease-free survival and overall survival in primary extranodal lymphoma. SUVmean is the most significant one amongst them for estimating recurrence/metastasis.

¿Pueden contribuir los parámetros tumorales metabólicos, establecidos mediante 18F-FDG PET/TC para estadificación primaria, a la estratificación del riesgo de los linfomas del sistema nervioso central, para el tratamiento del paciente como modelo pronóstico?

OBJECTIVEnPrimary central nervous system (CNS) lymphoma is an aggressive and fatal extranodal non-Hodgkin lymphoma jailed in CNS at initial diagnosis. Its prognosis is poor and the disease has a fatal outcome when compared with systemic non-Hodgkin lymphoma. A few baseline risk stratification scoring systems have been suggested to estimate the prognosis mainly based on serum lactate dehydrogenase level,age, Karnofsky performance score, involvement of deep brain structures and cerebrospinal fluid protein concentration. 18F-FDG PET/CT has a high prognostic value with respect to overall survival and disease-free survival in many cancers and lymphomas. We aimed to investigate metabolic tumor indexes on primary staging 18F-FDG PET/CT as prognostic markers in primary CNS lymphoma.nnnMATERIAL AND METHODSnFourteen patients with primary CNS diffuse large B-cell lymphoma (stage i) were enrolled in this retrospective cohort study. Primary staging 18F-FDG PET/CT was performed and quantitative parameters like maximum standardized uptake value, average standardized uptake value, metabolic tumor volume and total lesion glycolysis (TLG) were calculated for all patients before the treatment. Cox regression models were performed to determine their relation with survival time.nnnRESULTSnIn the evaluation of all potential risk factors impacting recurrence/metastases (age, sex, serum lactate dehydrogenase, involvement of deep brain structures, maximum standardized uptake value, average standardized uptake value, metabolic tumor volume, and TLG) with univariate analysis, TLG remained statistically significant (P=.02).nnnCONCLUSIONnMetabolic tumor parameters are useful in prognosis estimation of primary CNS lymphomas, especially TLG, which is the most important one and may play a role in patient management.

A different scintigraphic approach to evaluate the glomerular filtration rate

OBJECTIVEnMultiple nuclear medicine techniques for measuring renal glomerular filtration rate (GFR) are available but some of them are not practical in daily routine use and others have some accuracy issues. Hence the aim of the study was to design a new camera-based approach to measure the GFR and to compare our results with other measured GFR (mGFR) and estimated GFRs (eGFRs) derived from available measurements and equations used in daily clinical practice.nnnMATERIAL AND METHODSn34 patients were included in the study. ∼74MBq (2mCi) Technetium 99m diethylene-triamine-pentaacetic acid (99mTc-DTPA) was administered to the patients during 5min. A simple formula based on a dilution principle was used to measure GFR (ScinGFR).nnnRESULTSnOur formula provided similar mGFR results in narrower range as creatinine clearance did and our results correlated well with results derived from other equations. When ScinGFR values were compared to others, there was a significant difference among them (p=0.031) due to difference between the ScinGFR and Cockroft-Gault. When the results of the ScinGFR compared to others without Cockroft-Gault, the difference among them was not significant (p=0.164).nnnCONCLUSIONnA simple formula considering the extracellular fluid volume was used to predict the split and global kidney functions and despite some discrepancies, good correlation among our results and those derived from available formulas was detected.

An unusual presentation of primary hyperparathyroidism: multiple brown tumors and coexisting thyroid carcinoma

We present a patient with a complex clinical picture of primary hyperparathyroidism with multiple destructive skeletal lesions suspicious of bone metastases and concomitant multifocal papillary thyroid carcinoma with a metastatic central lymph node. He presented with progressively worsening right hip pain and restricted motion. Magnetic resonance imaging revealed multiple lytic lesions involving predominantly the right trochanter minor and the left inferior and posterior pubic rami. Biochemical tests were consistent with primary hyperparathyroidism. Neck ultrasound and parathyroid scintigraphy revealed a single parathyroid adenoma and a thyroid nodule, preoperative cytology of which confirmed papillary thyroid carcinoma, as did the final surgical specimen. Biochemical results, regarding hyperparathyroidism, declined to normal levels and his complaints gradually decreased after surgery. Postoperative whole body bone scintigraphy showed increased tracer uptakes at multiple sites, but they were proved to be metabolically inactive by fluorodeoxyglucose positron emission tomography/computed tomography.

Evaluation of variability of phase indices of the left ventricle in the course of time.

ObjectiveSince the effect of time on phase indices is still unclear, the aim of the study was to evaluate the variability of phase indices of the left ventricle which were derived from stress and rest single-photon emission computed tomography (SPECT) imaging acquired at early and late times.MethodsOne hundred twenty-one patients (72 men, 49 women) were included into the study. All stress and rest gated myocardial perfusion imaging (gMPI) acquisitions were acquired at two different time points as early in 15xa0±xa05xa0min and late in 45xa0±xa05xa0min. The peak of the phase histogram (PP), the standard deviation of the phase distribution (SDPH), the width of the band (BPH), and the symmetry (histogram skewness, HS) and peakedness of the phase histogram (histogram kurtosis, HK) which are the parameters for assessing left ventricular systolic dyssynchrony were calculated in all stress and rest SPECT images acquired twice.ResultsThe phase indices derived from the late rest scans were smaller than those of the early rest scans but, the differences were not significant. When considering the comparisons of phase indices derived from two different time points after stress, PP showed a tendency to decrease (from 160.8xa0±xa018.3 to 152.5xa0±xa017.3; pxa0<xa00.001) over time but SDPH (from 20.2xa0±xa010.6 to 22.4xa0±xa012.2; pxa0=xa00.018) and BPH (from 61.5xa0±xa036.0 to 66.3xa0±xa037.3; pxa0=xa00.045) tended to increase over time. When the post-stress and the resting dyssynchrony parameters derived at two different time points were compared to each other; PP decreased at early and late times approximately 12 and 9xa0%, respectively, SDPH increased at early and late times approximately 28.5 and 14xa0%, respectively, and BPH increased at early and late times approximately 23 and 12xa0%, respectively.ConclusionsIn resting conditions, phase indices of the left ventricle, and therefore, the phase histogram tend to remain constant over time but, in conditions after exercise, the phase histogram tend to be long and narrow due to changes in phase indices and it shows tendency to return to resting conditions in time. Therefore, it appears that postexercise acquisition times should be standardized if we want to compare the phase indices results of the studies in the literature.