BACKGROUND: Gastric carcinoma is one of the most common malignancies in the world. Skeletal muscle metastases from gastric carcinoma are rare.

CASE REPORT: We report a case of a 67-year-old man patient with skeletal muscle metastasis developing from gastric carcinoma. He had a painful swelling of the left thigh. A chest computed tomography (CT) scan with enhancement showed pulmonary thromboembolism. Despite heparin therapy, edema and pain of the lower limbs increased bilaterally, so the patient underwent pelvic magnetic resonance imaging (MRI), which documented an altered signal intensity in the upper third of his thighs bilaterally. Furthermore, the examination of the ultrasound (US)-guided biopsy specimen of the left gluteal muscle showed signet ring cell adenocarcinoma metastasis. An upper gastrointestinal tract endoscopy confirmed a gastric ulceration, with a biopsy positive for signet ring cell adenocarcinoma. Because of the advanced stage of disease, the patient underwent only supportive care and died 74 days after admission.

CONCLUSIONS: Skeletal muscle metastasis may be the initial presentation of gastric carcinoma and diagnosis could be difficult. Biopsy is mandatory for diagnosis.

Keywords: Carcinoma, Signet Ring Cell - therapy, Fatal Outcome, Muscle Neoplasms - therapy, Muscle, Skeletal, Thigh