Cutaneous Metastasis as a Presenting Feature of Renal Adenocarcinoma in a Renal Transplant Recipient: A Case Report

Metastatic Translocated Renal Cell Carcinoma in a Kidney Transplant Patient - a Case Report and Review of the Literature

TFEB-altered renal cell carcinomas are rare tumours. Here, we report the exceptional case of such a tumour in the setting of solid organ transplantation and with already metastatic disease at the time of diagnosis. The primary tumour occurred in the native kidney and only focally showed biphasic morphology whereas the metastasis, among others to the transplant kidney, showed nonspecific, albeit different morphology, but both had consistent TFEB translocation. Treatment with the immune checkpoint inhibitor pembrolizumab together with the multi-kinase inhibitor lenvatinib achieved partial response 14 months after diagnosis.

Isolated soft tissue mass of the finger as the first presentation of oligometastatic renal cell carcinoma

A man in his 70s was referred to plastic surgery with a suspected foreign body in the pulp of his right index finger. An excisional biopsy was performed for a presumed foreign body granuloma. Histology revealed metastatic renal cell carcinoma (mRCC). CT imaging demonstrated a 7.4 cm heterogeneous mass arising from the upper pole of the left kidney consistent with primary renal malignancy, in addition to a 9 mm lung nodule. He underwent an uncomplicated left laparoscopic cytoreductive nephrectomy and made a satisfactory recovery. To our knowledge, this is the first reported case of primary mRCC presenting with digital soft tissue metastasis. Cytoreductive nephrectomy with metastasectomy is the preferred management for mRCC where feasible. For unfavourable mRCC cases, first-line systemic therapy is indicated. Adjuvant systemic therapy in mRCC is currently limited to clinical trials, though promising data emerging on the use of pembrolizumab may herald a future shift in practice.