ABSTRACT
Prostate cancer is one of the most common malignancies affecting elderly men worldwide and the fifth leading cause of cancer death in men. Prostate cancer includes many histological variants with the prostatic acinar adenocarcinoma variant accounting for the majority of the diagnosed cases. Other less common histological variants are broadly classified as non-acinar carcinomas. One of the non-acinar carcinoma variants is neuroendocrine prostate cancer (NEPC). NEPC can emerge as a mechanism of treatment resistance in castration-resistant conventional prostate cancer and can also rarely be seen as a primary histological form at the time of initial diagnosis. Like other non-acinar carcinoma variants of prostate cancer, NEPC is also an aggressive variant with associated poor prognosis. Neuroendocrine tumors (NETs) are characterized by the expression of somatostatin receptors (SSTRs). Positron emission tomography/computed tomography (PET/CT) using radiolabeled somatostatin analogs like DOTANOC have been used to detect and stage these NETs. These radiolabeled somatostatin analogs also provide the option of treatment of these tumors and have been used in peptide receptor radionuclide therapy of these tumors. NEPC being a neuroendocrine malignancy also expresses SSTRs and hence can be detected with PET/CT radiotracers like 68Gallium-labeled somatostatin analogs. We here report a case of metastatic treatment-emergent NEPC detected on 68Ga - DOTANOC PET/CT.
ABSTRACT
Positron emission tomography (PET) is an integral part of the imaging of solid tumors in today's oncology practice. The most commonly used PET radiotracer is 18F-Fluorodeoxyglucose (18F-FDG). FDG PET has imaging characteristics of a high tumor-to-background uptake ratio and is used in the detection of primary as well as metastatic sites. However, a significant pitfall is its inability to differentiate between neoplastic and infective lesions. To address this concern, many PET radiotracers have been developed and tried over time, a promising one being radiolabelled fibroblast activation protein inhibitor (FAPI). Fibroblast-activated protein (FAP) is a type II transmembrane glycoprotein expressed by cancer-associated fibroblasts (CAFs); it forms a significant component of the tumor stroma. Since there is over-expression of CAF in the majority of malignancies, it is a potential target for molecular imaging using PET. Several radiolabeled FAP inhibitors have been developed for PET imaging of malignancies and have also been used in theranostic applications.
ABSTRACT
ABSTRACT: Gallbladder neuroendocrine neoplasms (NENs) are rare tumors of the biliary system. These neoplasms express somatostatin receptors, and hence radiolabeled somatostatin analog 68Ga-DOTANOC is used as a PET radiotracer in detection and staging. Gallbladder NEN cannot be differentiated from an adenocarcinoma of the gallbladder based on clinical symptoms or routine radiological imaging such as ultrasound or CT. These are either diagnosed postcholecystectomy or after biopsy from primary or metastatic sites. We present a rare case of gallbladder NEN detected on 68Ga-DOTANOC PET/CT.
Subject(s)
Neoplasms, Second Primary , Neuroendocrine Tumors , Organometallic Compounds , Gallbladder/diagnostic imaging , Gallbladder/pathology , Humans , Neuroendocrine Tumors/diagnostic imaging , Neuroendocrine Tumors/pathology , Positron Emission Tomography Computed Tomography/methodsABSTRACT
Cervical cancer is one of the common gynaecological malignancies seen in women. As per the World Health Organization (WHO), cervical cancer is the fourth most common malignancy encountered in women worldwide. Squamous cell carcinoma followed by adenocarcinoma is the most common histological subtype of cervical cancer. Apart from nodal metastases, the usual sites of metastases are the lungs, bones, and liver. Spleen, breast, and skin have been reported as rare sites of metastasis in cases of cervical cancer. Spleen is a rare site of metastasis not only in cases of carcinoma cervix but also in various other solid tumour malignancies. Splenic metastases being uncommon are difficult to characterise using routine imaging modalities. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) evaluation helps to detect these rare sites of metastasis.
