Metastatic Osteosarcoma of Mandible
February 4, 2020
Cardiac PET/MRI
February 5, 2020

Neuro-Endocrine Tumors


Neuroendocrine tumors (NET’s) represent a large spectrum of the heterogeneous group of malignancies that are derived from embryonic neural crest tissue. The spectrum of neuroendocrine tumors range from:

  • Carcinoid tumors: Arising from enterochromaffin cells and can occur at various sites such as thymus, lung, ovary
  • Pheochromocytoma adrenals/extra-adrenal sites gastrointestinal tract neuroendocrine tumors
  • Pancreatic neuroendocrine tumors (pNET)
  • Pulmonary neuroendocrine tumors
  • Medullary Thyroid Tumours

Diagnostic imaging plays a pivotal role in the diagnosis, staging, treatment selection and follow-up for neuroendocrine tumors. CT and MRI are well-suited for discerning small lesions that might escape detection by single-photon emission tomography (SPECT) or PET, as well as for assessing the local invasiveness of the tumor or the response to therapy. PET with 68Ga-labelled somatostatin analogues performs better than somatostatin receptor scintigraphy. Similarly, MRI performs better than CT with various image contrast complementing or supplementing PET avidity in the identification and characterization of metastasis in liver, bone and soft tissue.


Case 1: Mulitple Paragangliomas


Case History:

26 year old female with a carotid body tumor in the left neck. Underwent Ga-68 DOTATATE PET/CT and complementary PET /MR.


Findings:

Contrast CT at level of skull base (A) and at the level of carotid bifurcation (B) and their corresponding PET CT fused images (B,D) reveal an enhancing avid mass (* in D) in the left neck at the level of carotid bifurcation ( presenting complaint). In addition, three additional smaller areas of DOTATATE uptake were seen in the bilateral jugular bulb and the right carotid bifurcation (arrows) which were not well identifiable on CECT.

Complementary PET/MRI was performed at the same time which revealed DOTATATE avid areas in the bilateral jugular bulb and bilateral carotid bodies similar to CT. However, the greater anatomical details on MRI delineate the enhancing tumors well in relation to the vessels (arrows in I, J).


Case 2: Duodenal Carcinoid


Case History:

56 year old male with suspected Neuroendocrine tumor.


Findings:

Post-contrast VIBE arterial phase(A), T2 Axial (C) and PET/MR fused(B, D) reveal subcentimeter DOTANOC avid nodular thickening with early arterial phase enhancement(A, B, C, D) is seen along the medial wall of the first part of duodenum(arrow in B and C).


 

Case 2: Pancreatic NET With Liver Metastasis


Case History:

27 year old female with suspected Neuroendocrine tumor.


Findings:

Post-contrast (A, C) and PET/MRI fused images(B, D) show arterial enhancing Ga-68 DOTATATE avid mass is noted in the pancreatic head and uncinate process (arrow) with similar intensity lesions in the liver (arrows).


Key Message:

The high-resolution triple-phase images permit the identification of subcentimeter arterial phase enhancing lesions and simultaneous acquisition of the PET allows accurate co-registration of MR and PET images which is often not possible with CT and PET owing to interscan motion during sequential acquisition of CT and PET.


Case Study Prepared by:

This short PET-MRI Scan case was compiled by Dr. Sangeeta Taneja and Dr. Amarnath Jena (Nuclear Medicine Physician at PET-Suite @ Indraprastha Apollo Hospital, Sarita Vihar).


Read More about PET-MRI Scan at House Of Diagnostics in Delhi and NCR.

The Simultaneous PET-MRI Scan is currently offered at PET-Suite at Apollo Hospital, Sarita Vihar.