Capecitabine-Temozolomide in Advanced Grade 2 and Grade 3 Neuroendocrine Neoplasms: Benefits of Chemotherapy in Neuroendocrine Neoplasms with Significant 18FDG Uptake.

INTRODUCTION: Capecitabine-temozolomide (CAPTEM) chemotherapy, alone or with concurrent peptide receptor radionuclide therapy (PRRT), has activity in advanced WHO grade 2 and grade 3 neuroendocrine neoplasms (NENs). The objective of this study was to evaluate the activity of the CAPTEM in patients with grade 2 and grade 3 NENs and identify prognostic factors. MATERIALS AND METHODS: A retrospective analysis of patients with metastatic grade 2 and grade 3 NENs, who were having baseline significant dual uptake on 68Ga-DOTATATE/18F-fluorodeoxyglucose (FDG)-PET-CT scan and treated with CAPTEM chemotherapy between January 2014 and December 2019 at Tata Memorial Hospital, was conducted. The clinical variables and survival data were collected. Progression-free survival (PFS) was estimated using the Kaplan-Meier method. RESULTS: A total of 68 patients received the CAPTEM regimen, of whom 29 patients (43%) received CAPTEM alone and 39 patients (57%) received concurrent PRRT. The primary sites were pancreas in 32 (47%) and small intestine in 12 (18%) patients. Mean Ki-67 index was 12.6% (range: 3-50). Forty-five patients (65%) were treatment naïve. There were no significant differences in baseline clinical variables between patients treated with CAPTEM alone or with CAPTEM-PRRT. Both regimens were well tolerated. With a median follow-up of 22.1 months, the median PFS for the entire cohort was 27.5 months. There was no statistical difference in the median PFS between patients receiving CAPTEM alone or CAPTEM-PRRT (33.7 vs. 22 months; p = 0.199). A Ki-67 index of >5% predicted for inferior PFS on multivariate analysis (24 versus 73.8 months; p = 0.04; hazard ratio -3.77; 95% confidence interval: 1.07-13.26). CONCLUSION: CAPTEM, alone or concurrent with PRRT, has a significant activity in grade 2 and grade 3 NENs with dual SSTR and 18FDG expression. A Ki-67 index >5% predicts strongly for inferior outcomes and should be further explored as a prognostic cutoff in grade 2 NENs. Early initiation of CAPTEM should be considered in this group of tumors with significant baseline 18FDG expression.

Usefulness of Tc99m-mebrofenin Hepatobiliary Scintigraphy and Single Photon Emission Computed Tomography/Computed Tomography in the Diagnosis of Bronchobiliary Fistula.

Bronchobiliary fistula (BBF), a rare complication of liver disease, is an abnormal communication between the biliary tract and bronchial tree. BBF may occur as a consequence of local liver infections such as hydatid or amebic disease, pyogenic liver abscess or trauma to the liver, obstruction of biliary tract, and tumor. As such management of liver disease with BBF is very difficult and often associated with a high rate of morbidity and mortality. Therefore, timely diagnosis of BBF is imperative. Hepatobiliary scintigraphy along with hybrid single photon emission computed tomography/computed tomography using Tc99m-mebrofenin is a very useful noninvasive imaging modality, in the diagnosis of BBF.

Presentation of Unusual Tracheal Metastasis on Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography after 9 Years in Postnephrectomy Patient of Renal Cell Carcinoma: A Case Report and Review of Literature.

Tracheal metastases from renal cell carcinoma (RCC) are extremely rare. Most common primary malignancy metastasizing to this unusual location usually comes from lung region while it is rare to have tracheal metastases from nonpulmonary malignancies such as breast, thyroid, colorectal carcinoma, and melanoma. The lesions detected on fluorine-18 fluorodeoxyglucose (F-18 FDG) positron emission tomography/computed tomography (PET/CT) scan, especially in the head and neck region, soft tissue, and muscular compartment during follow-up of RCC patients raise the possibility of metastatic lesions in these regions, though rarely encountered. F-18 FDG PET/CT proved to be a valuable noninvasive imaging tool in detecting the very unusual distant metastases and multisystem involvement many years after nephrectomy in RCC in a single session in the present case.

Designing and Developing PET-Based Precision Model in Thyroid Carcinoma: The Potential Avenues for a Personalized Clinical Care.

This communication enumerates the current uses and potential areas where PET could be clinically utilized for developing "precision medicine" type model in thyroid carcinoma. (1) In routine clinics, PET imaging (with fluorodeoxyglucose [FDG]) is utilized to investigate patients of differentiated thyroid carcinoma (DTC) with high thyroglobulin and negative iodine scintigraphy (TENIS) and in medullary carcinoma thyroid (MCT) when the tumor markers (eg, calcitonin and carcino embryonic antigen [CEA]) are raised postoperatively (PET with FDG, 68Ga-DOTA-NOC/TATE, FDOPA). Both are examples of management personalization, where PET-computed tomography (CT) has been found substantially useful in detecting sites of metastatic disease and making decision with regard to feasibility and planning of surgery on an individual patient basis. (2) The next important area of management personalization is in patients of TENIS with metastatic disease not amenable to surgery through examining FDG-PET findings in tandem with radio iodine scan and 68Ga-DOTA-TATE/NOC PET/CT. Heterogeneous behavior of the metastatic lesions is frequently observed clinically: analyzing the findings of three studies aids in sub-segmenting patients into subgroups and thereby deciding upon the best approach (observation with LT4 suppression vs PRRT vs tyrosine kinase inhibitors) that could be individualized in a given case. (3) In metastatic/inoperable MCT, 68Ga-DOTA-TATE/NOC PET-CT helps in deciding upon feasibility of targeted PRRT in an individual patient and helps in follow-up and response evaluation. (4) Disease prognostification with FDG-PET is evolving both in DTC and MCT, where FDG avidity would indicate an aggressive biology, though the implication of this from treatment viewpoint is unclear at this point. Conversely, a negative FDG-PET in DTC and TENIS would suggest a favorable prognosis in an individual. (5) Iodine-124 PET/CT has the added potential of obtaining lesional dosimetry compared to the SPECT approach, and could help in selecting appropriate doses on an individual basis.

Grouping of Metastatic Thyroid Carcinoma by Molecular Imaging Features to Allow for Individualized Treatment, with Emphasis on the TENIS Syndrome.

The process of radioiodine ((131)I) refractoriness, dedifferentiation, and development of thyroglobulin elevation and negative iodine scintigraphy (TENIS) syndrome in metastatic differentiated thyroid carcinoma (DTC) could be viewed as a disease continuum rather than a single event or an all-or-none phenomenon. In this report, the important role of molecular functional imaging in systematically exploring the disease biology and course of metastatic DTC is presented. Making this role the base, this report proposes a novel clinical classification for TENIS syndrome using molecular functional imaging. Such an endeavor, in our view, would aid in classification into subgroups and development of an individualized treatment strategy for patients with metastatic DTC. Case illustrations are presented that substantiate this viewpoint, including the value of combined assessment in selected cases and the requirement of a multipronged treatment approach for certain case scenarios. In addition to multiple other considerations, we believe that molecular functional imaging-based characterization of metastatic lesions could evolve as an important determinant for defining the optimal treatment strategy in patients with metastatic DTC, making the clinical management more rational and scientific.

Multiple Brown Tumors Caused by a Parathyroid Adenoma Mimicking Metastatic Bone Disease from Giant Cell Tumor.

Brown tumor affects multiple bones in the body with variable clinical symptoms, which may be misdiagnosed as multiple bone metastases or primary bone tumor. In the present case report, we report the usefulness of 99mTc-MDP bone scan and 99mTc-MIBI whole body scan in differentiating brown tumor of hyperparathyroidism from giant cell tumor.

Paraganglioma and pancreatic neuroendocrine tumor with rare metastatic sites detected on 68Ga-DOTATATE PET/CT imaging.

Pancreatic neuroendocrine tumors (PNETs) represent a small percentage of all pancreatic malignancies, and most of these present as metastatic disease. Somatostatin receptor scintigraphy had been used successfully for the assessment of patients with NET. Somatostatin receptor scintigraphy is indispensable for localization of ectopic NET and the distribution of NET throughout the body.

68Ga DOTATATE PET/CT in a rare coexistence of pituitary macroadenoma and multiple paragangliomas.

The coexistence of a pituitary neoplasm and pheochromocytoma is a rare condition, which may be another undefined variant of Multiple endocrine neoplasia (MEN) syndrome. Moreover, the coexistence of pituitary macroadenoma and multiple paragangliomas is more uncommon and only few authors have reported these findings. We are reporting the use of Ga DOTATATE PET/CT in a rare case of coexisting pituitary macroadenoma and multiple paragangliomas.

68Ga DOTATATE PET/CT imaging of a solitary fibrous tumor of the nasopharynx.

Solitary fibrous tumors (SFTs) are rare group of mesenchymal tumors that occurs predominantly in the pleura. The role of PET/CT imaging in characterizing the SFT is not well reported. Mesenchymal tumors may express somatostatin receptors. We hereby report a rare case of SFT of the nasopharynx showing Ga DOTATATE avidity.