Multiple muscle metastases of the renal cell carcinoma after radical nephrectomy

Skeletal Muscle Metastasis From Renal Cell Carcinoma: A Case Series and Literature Review

Objectives

Skeletal muscle metastasis (SMM) from renal cell carcinoma (RCC) has been rarely reported. This case series was performed to increase the clinicians' understanding of its clinical features and treatments.

Methods

We evaluated the clinical presentations, diagnoses, and treatments of 2 patients with SMM from RCC in our hospital and 39 cases reported in the literature.

Results

Among the 41 patients, 4 (9.76%) were women and 37 (90.24%) were all men. The average age was 60.5 ± 12.6 years old (range from 7 to 81). The size of tumors varied from 1 to 28 cm, and the metastatic sites of 6 (14.63%) cases were in the heads, 20 (48.78%) in the limbs, 9 (21.95%) in the trunks, 3 (7.32%) in the buttock, and the other 3 (7.32%) were multiple sites. The mean of intervals between the RCC and the discovery of the first SMM was 73.61 months. More than half of the patients (25, 60.98%) were diagnosed by MRI and 25 (60.98%) patients performed a biopsy of the mass to establish the diagnosis. Finally, 30 (73.17%) cases performed mass excision. Then the adjuvant therapy was performed in 18 patients including immunotherapy, radiotherapy, chemotherapy, and targeted therapy. The median follow-up after SMM was 9 months (P25, P75: 5, 23), in which the longest survival time of patients with SMM of RCC was 8 years while the shortest was only 3 months.

Conclusion

The characteristic clinical feature of SMM from RCC is asymptomatic masses or swelling with a long history which can be preoperative suspiciously diagnosed by MRI. The rapid biopsy of suspected lesions, determination of other metastasis sites, resection of metastasis, and systematic treatment are the recommended treatments of it.

Rare skeletal muscle metastasis from renal cell carcinoma: case report and review of the literature

Renal cell carcinoma (RCC) is a tumor that usually metastasizes to lung, liver, bone and brain, but rarely to skeletal muscles. We report a case of an elderly man with a history of bilateral metachronous RCC for which he underwent curative bilateral nephrectomies and renal transplantation, was in remission, and presented with a large solitary skeletal muscle metastasis from the initial RCC, 3 years later.

[Muscular metastases from renal cell carcinoma]

Renal cell carcinoma can metastasize to several locations but rarely in muscles. However, this possibility must never be overlooked because muscle metastases may occur a very long time after the initial nephrectomy. So the post-operative follow-up, according to the recommendations, with thoraco-abdomino-pelvic imaging (computed tomography or nuclear magnetic resonance) allowing to detect metastases, including muscle metastases in the trunk, does not have to neglect the metastases located in the members. This search is based upon a thorough clinical examination, completed by targeted imaging in case of symptoms and/or palpable mass.