title: Case report: case of clear cell sarcoma surviving with the primary lesion for 20 years after resection of a metastatic lymph node.
abstract: In this paper we report on an extremely rare case of clear cell sarcoma, which is a rare malignant soft tissue tumor, biologically similar to malignant melanoma. The patient has survived for 25 years after he noticed a small tumor mass at the wrist and for 20 years after a small sentinel lymph node metastasis in the axilla was removed by surgical resection. The patient visited us because the tumor in his wrist had increased rapidly in size during the previous year. We diagnosed the wrist tumor as a clear cell sarcoma, based on the typical histopathological findings and positivity of the tumor cells for HMB-45 and S-100 protein; the histopathological findings in the axillary soft tissue tumor resected 20 years previously were also compatible with clear cell sarcoma of the lymph node. Therefore, we concluded that the wrist tumor was the primary lesion of clear cell sarcoma and that the axillary tumor was a metastatic lesion in a sentinel lymph node. Generally, the prognosis of clear cell sarcoma is very poor, especially after the occurrence of lymph node metastasis. In this case, it is possible that certain immune mechanisms played a role in effectively suppressing the tumor growth for such a prolonged period, even after the development of lymph node metastasis.
authors.affiliation: Department of Orthopaedic Surgery, Mie University School of Medicine, Mie, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Okamura
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Kusuzaki
authors.forename: Akihiko
authors.initials: A
authors.lastname: Matsumine
authors.forename: Masashi
authors.initials: M
authors.lastname: Seto
authors.forename: Kazuo
authors.initials: K
authors.lastname: Fukutome
authors.forename: Atsumasa
authors.initials: A
authors.lastname: Uchida
mesh_terms: D006801:Humans; D008197:Lymph Node Excision; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology / Q000601:surgery; D018227:Sarcoma, Clear Cell / Q000473:pathology* / Q000601:surgery; D012983:Soft Tissue Neoplasms / Q000473:pathology* / Q000601:surgery; D014953:Wrist / Q000473:pathology / Q000601:surgery