Rectal Carcinoma Metastases to Multiple Skeletal Muscles-Role of F-18 FDG PET/CT.

Rectal carcinoma with metastasis to skeletal muscle is rare. So far, 16 cases of skeletal muscle metastasis from colorectal carcinoma have been documented of which only 5 were rectal carcinomas. We discuss here the case of a 69-year old male, a known case of mucinous adenocarcinoma status post neoadjuvant chemoradiotherapy and abdomino perineal resection, who presented with low backache 4 months post surgery. He was found to have metastasis to multiple skeletal muscles without the involvement of common sites, such as liver and lung. The role of 18-FDG-PET/CT in such cases is rarely reported in the literature. This case highlights the importance of utilizing 18-FDG-PET/CT in detecting sites of skeletal muscle metastasis and thereby guides appropriate management.