Peptide Receptor Radionuclide Therapy of Neuroendocrine Tumors.

Peptide receptor radionuclide therapy (PRRT), over the years, has evolved as an important modality in the therapeutic armamentarium of advanced, metastatic or inoperable, progressive Neuroendocrine Neoplasms (NENs). This review deliberates on the basic understanding and applied clinical aspects of PRRT in NENs, with special reference to (1) tumor biology and receptor characteristics, (2) molecular PET-CT imaging (in particular the invaluable role of dual-tracer PET with [68Ga]-DOTA-TATE/NOC and [18F]-FDG for exploring tumor biology in continuum and individualizing treatment decision making) and NEN theranostics, (3) relevant radiochemistry of different therapeutic radionuclides (both beta emitting 177Lu-DOTATATE and 90Y-DOTATATE and alpha emitting 225Ac-DOTATATE), and (4) related dosimetric considerations. Successful clinical management of the NENs would require multifactorial considerations, and all the aforementioned points pertaining to the disease process and available logistics are key considerations for state-of-the-art clinical practice and delivering personalized care in this group of patients. Emphasis has been placed on relatively intriguing areas such as (1) NET grade 3 of WHO 2017 classification (ie, Ki-67>20% but well-differentiation features), (2) "Neoadjuvant PRRT," (3) combining chemotherapy and PRRT, (4) 'Sandwich Chemo-PRRT', (5) duo-PRRT and tandem PRRT, (6) resistant functioning disease with nuances in clinical management and how one can advocate PRRT rationally in such clinical settings and individualize the management in a patient specific manner. Relevant clinical management issues related to some difficult case scenarios, which the Nuclear Medicine attending physician should be aware of to run an efficient clinical PRRT services, are described.

Spectrum of hemoglobin variants in the population of northern region of west bengal: an ethnogenetic proposition.

CONTEXT: The birth of transfusion-dependent states of hemoglobinopathies including thalassemias is preventable by population screening and genetic counseling. Magnitude is not addressed in the Northern Region of West Bengal where many ethnic variants inhabit. AIMS AND OBJECTIVES: The aim of the following study is to find out the burden of different entities of hemoglobinopathies, their correlation with ethnicity and the "at risk" groups. SUBJECTS AND METHODS: A descriptive study was conducted from the Hematology Unit of North Bengal Medical College over 1 year on the subjects underwent screening for hemoglobinopathies for detection of abnormal hemoglobin (Hb) variants by "cation-exchange high-performance liquid chromatography" principle along with other relevant tests. STATISTICAL ANALYSIS: Data was analyzed by frequency distribution and Chi-square test assuming P value as 95% of the level of significance using the SPSS version 16 (SPSS Inc., Chicago, Illinois, U.S.A). RESULT: Abnormal Hb variant was 47.5% among 1872. Hb E trait (34.4%) was most common followed by Hb E disease (25.3%) and others. Hb E disorders (92.7%) were observed mostly among Rajbangsi population while E-ß-thalassemias (40%) in the Muslims and a heterogeneous pattern noted among tribal and mongoloid. CONCLUSION: Hb E hemoglobinopathies was high among Rajbangsi and Muslims with identification of some other hemoglobinopathies involving tribal and mongoloid.

'Reverse discordance' between 68Ga-DOTA-NOC PET/CT and 177Lu-DOTA-TATE posttherapy scan: the plausible explanations and its implications for high-dose therapy with radiolabeled somatostatin receptor analogs.

In this technical note, an unusual discordance between diagnostic and posttherapeutic scan resulting from the use of different somatostatin receptor ligands in two settings is described. Such observation, we believe, is multifactorial, but most importantly arises due to different receptor affinity profile of the ligands and different somatostatin receptor subtype expression in different tumors. It is important for the treating physician to be aware of this phenomenon that would aid in improving our understanding of complex ligand-receptor interactions in various somatostatin receptor-positive tumors with its possible implications for therapeutic decision making with radiolabeled somatostatin receptor analogues.