腎細胞癌合併皮膚轉移及骨髓增生異常症候群之罕見病例報告

薛丞勛、陳生文、程威銘、張彰琦

臺北市立聯合醫院忠孝院區外科部泌尿科

A Case Report: Renal Cell Carcinoma with Cutaneous Metastasis and a Concurrent Myelodysplastic Neoplasm

Cheng-Hsun Hsueh, Sheng-Wen Cheng, Wei-Ming Cheng, Chang-Chi Chang

Division of Urology, Department of Surgery, Zhongxiao Branch, Taipei City Hospital

Introduction

Renal cell carcinoma (RCC) is a heterogeneous malignancy with a wide range of clinical presentations and associations with other systemic diseases. Approximately 33% of RCC cases present with metastatic disease, with the most common metastatic sites being the lungs, liver, bones, brain, and adrenal glands^[1]. Cutaneous metastasis from RCC is rare, accounting for only 3–5% of all metastatic RCC cases^[2]. Cutaneous metastases typically present as round or oval-shaped nodules, which can vary in color from skin-toned to purple^[3]. Additionally, RCC has been reported to be associated with certain myeloid malignancies^[4]. Here, we present the case of a 77-year-old male with RCC who developed both cutaneous metastasis and a concurrent myelodysplastic neoplasm.

Case presentation

A 77-year-old male with a medical history of type 2 diabetes mellitus, hypertension, and stage 3 chronic kidney disease presented with unintentional weight loss of more than 10 kilograms over the preceding six months. Laboratory investigations revealed microcytic anemia, leukocytosis, thrombocythemia, and an elevated serum creatinine level. Based on these findings, a myeloid malignancy was suspected by the hematologist. Bone marrow biopsy results were consistent with an unclassifiable myelodysplastic/myeloproliferative neoplasm. Abdominal ultrasonography identified a mass measuring 6.8 × 6.9 cm in the lower pole of the right kidney. Abdominal computed tomography (CT) further characterized a 5.2 × 5.4 × 5.5 cm ill-defined, heterogeneous mass located at the interpolar region of the right kidney, with involvement of the right main renal vein and inferior vena cava. The imaging also revealed osteolytic lesions in the bilateral ribs, a metastatic lesion in the left 7th rib, multiple nodules of varying sizes in both lung fields, and several small subcutaneous nodules located on the left chest wall and upper trunk. A core needle biopsy of the left chest wall subcutaneous mass was performed under ultrasound guidance, which revealed a poorly differentiated carcinoma with sarcomatous differentiation. Immunohistochemical staining of the biopsy specimen was positive for vimentin and cytokeratin (CK) but negative for CD117, suggesting a metastatic RCC origin. The patient was subsequently treated with chemotherapy, specifically doxorubicin.

Conclusion

This case represents a rare presentation of RCC with both cutaneous metastasis and an associated myelodysplastic syndrome. To the best of our knowledge, this is the first documented case of RCC presenting with these two uncommon manifestations. The case underscores the diverse clinical spectrum of RCC and highlights the importance of further investigation into the underlying mechanisms that link RCC with various hematologic and metastatic diseases.