Журнал клинических случаев

Isolated Metastases in the Elbow as the First Presentation of Metastatic Colorectal Cancer A Case Report and Overview of Literature

Abstract

Tanja Mesti, Sasa Rink, Karolina Pocivavsek and Janja Ocvirk

Introduction: Colon adenocarcinoma frequently metastasizes to the liver and lung. Distant metastasis to skeletal muscle and subcutaneous tissues arising from colorectal cancer are rarely reported in the literature. Treatment options include radiotherapy, chemotherapy and surgical excision, with no standard treatment. Case presentation: A 64 years old male presented with painful mass in the left elbow (8.5x5.5 cm). The incisional biopsy of the tumor showed poorly differentiated carcinoma, with no clear differentiation between epitheloid sarcoma or low differentiated carcinoma metastasis. PET CT showed pathological metabolic activity in the left elbow and in the right part of the abdomen. Colonoscopy was performed, showing an ulcerated obliterating adenocarcinoma of the sigmoid colon. Hemicolectomy followed. The histological comparison of the both tumors, showed the same characteristics. Molecular analysis showed biomarkers non mutated status. The radiotherapy of the elbow was applied, and he started with combination of doublet chemotherapy and EGFR inhibitor. After three cycles, complete remission was achieved, remaining present. Due to complete regression surgical resection was not necessary. Conclusion: We have reported an extremely rare case of isolated skeletal muscle metastasis as first presentation of metastatic colon adenocarcinoma. PET CT can be helpful to localize the primary site of the metastatic deposits. Immunostaining and pathohistological comparison of the primary carcinoma and the metastasis should be incorporated to reach the final diagnosis whenever possible. Since skeletal muscle metastases are considerably rare and the therapy is not standardized, treatments of these patients should be individualized and must depend on the clinical settings and biomarkers status.