Delineation of Carcinoid Tumor Metastases in Myocardium
Symbia T16 SPECT•CT imaging with 111In Octreotide
Case study data provided by Dr. Everett Chalmers Regional Hospital, Fredericton, New Brunswick, Canada
A 74-year-old male with a history of intestinal carcinoid tumor removed during a routine colonoscopy was evaluated with a follow-up CT that demonstrated numerous enlarged mesenteric lymph nodes. Chromogranin A levels were also elevated. The patient was referred for an Indium- 111 (111In) Octreotide SPECT•CT study.
Scanner: Symbia T16
Dose: 6 mCi 111In Octreotide
Scan Delay: 60 frames, 30 sec/frame
CT: 130kV, 30 eff mAs, 3 mm slice
The study shows focal areas of increased uptake of 111In Octreotide in the enlarged lymph nodes at the root of the small bowel mesentery (red arrows) is suggestive of carcinoid tumor metastases. A small area of increased uptake in the right ascending colon appears suspicious and local tumor recurrence cannot be ruled out. There is a small focal area of increased uptake in the thorax that corresponds to the left ventricular apex (white arrows), which is suggestive of focal myocardial metastases. The myocardial lesion measured 0.9 cm in size.
Metastases from a carcinoid within the left ventricular myocardium are rare. A 2010 publication by Jann et al1, identified a total of 41 published case studies related to left ventricular carcinoid metastases. Most cases involved a primary tumor localized to the mid gut. Carcinoid syndrome was reported for 28 patients. The location of metastases was similar for both ventricles. Clinical presentation ranged from asymptomatic patients to cardiac arrest. 111In Octreotide SPECT•CT provides comprehensive characterization and localization of carcinoid metastases, especially in locations like the heart where accurate localization is difficult with SPECT only. In this case, SPECT imaging could visualize the focal thoracic lesion, which appeared to be a lung metastases that was clarified by SPECT•CT based localization. Symbia™ T16's integrated 16-slice diagnostic CT provides fast acquisition that enables breath-hold imaging to reduce respiratory motion, as well as myocardial motion artifacts allowing accurate fusion of SPECT and CT for proper lesion localization. The high-resolution Symbia T16 is able to provide the clarity and sharpness required for the visualization of the smallest diagnostic detail such as small myocardial lesion.
- A matter of the heart: myocardial metastases in neuroendocrine tumors. Jann H, Wertenbruch T, Pape U, Ozcelik C, Denecke T, Mehl S, Wiedenmann B, Pavel M. Horm Metab Res. 2010 Dec; 42(13):967-76.