An 83-year-old man underwent curative resection for ascending colon cancer (Picture 1). He experienced a gradual onset of pain in the back of his neck starting six months after the surgery. Computed tomography 11 months postoperatively showed an irregular mass in the cervical skeletal muscle (Picture 2). A biopsy of the mass revealed adenocarcinoma. He was prescribed palliative radiation therapy because of his poor performance status. His symptoms improved, but he died two months later. The autopsy report revealed a 7.9-cm irregular mass in the cervical skeletal muscle consistent with muscle metastases (MM) of colorectal cancer (Picture 3) but no metastases in the liver or lung and no other primary tumors. The thigh muscles and extraocular musculature are the most common sites of skeletal MM (1). MM commonly presents as a painful, firm, and tender mass (2). Therefore, in cases with gradually worsening pain, we suggest MM be considered as a rare differential diagnosis for the pain.
Picture 1.
Picture 2.
Picture 3.
The authors state that they have no Conflict of Interest (COI).
References
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