Review Question - QID 214011

Solitary metastatic renal cell carcinoma (RCC) lesions should be treated with en bloc resection and reconstruction.

Treatment of bone metastatic lesions can vary due to several factors including diagnosis, location, and the number of metastases. Specifically for metastatic RCC, patients have lower rates of recurrence and revision surgery with en bloc resection and reconstruction for solitary metastatic lesions. Another treatment option for RCC metastases includes intralesional curettage with bony stabilization. In these patients, it is important to consider preoperative embolization as these lesions can be highly vascular.

Lin et al retrospectively reviewed 295 cases of metastatic renal cell carcinoma to investigate factors affecting survival. They found that patients with solitary boney metastases had the most favorable overall survival rate. Additionally, the clear cell subtype has the best prognosis. Postoperative radiation did not affect the rates of local recurrence.

Higuchi et al retrospectively analyzed 58 patients with metastatic RCC for factors associated with prognosis. 46 patients underwent en bloc resection and 12 underwent intralesional curettage. Overall survival at one, three, five, ten, and 15-years was 89%, 75%, 62%, 48%, and 25%, respectively. They found a statistically higher rate of relapse-free survival in patients who underwent en bloc resection compared to intralesional curettage (97.6% vs 35.8% at five years). Factors that had worse associated prognosis included non-clear cell type RCC and multiple metastatic lesions.

Yang, Abad, and Sherry review the treatment of oligometastases after successful immunotherapy for RCC and metastatic melanoma. They discuss the use of recombinant human IL-2 as a treatment in metastatic RCC, which has an 18-35% response rate, 1/3 of which had a complete response, and an only minority of these complete responders had a recurrence. Patients who had recurrence had a 32% 5-year survival after metastasectomy.

Figure A shows an AP and lateral Xrays of a right hip with a large lytic lesion involving the peritrochanteric region. Figure B is a sagittal CT scan cut that demonstrates multiple lytic lesions diffusely throughout the lumbar spine without evidence of collapse. Figure C is an AP of the left hip that demonstrates a lytic lesion in the subtrochanteric region involving >2/3rds of the canal. Figure D is a right shoulder AP Xray with an ill-defined lytic lesion with a punched-out appearance involving the humerus, clavicle, and scapula. Figure E is a lateral of a knee with a diffuse lytic and mottle appearing lesion of the proximal tibia and cortical thickening.

Illustration A is an intraoperative photograph of the resected renal cell carcinoma metastatic lesion en bloc with proximal femoral replacement to be used for reconstruction. Illustration B is an AP pelvis showing the final proximal femoral replacement reconstruction in place.

Incorrect Answers:
Answer 2: Multifocal spinal metastases without neurologic symptoms is often best treated with radiation.
Answer 3: This patient has a metastatic thyroid carcinoma lesion and is at risk for a pathologic fracture. This would best be treated with curettage and intramedullary nailing.
Answer 4: Treatment of multiple myeloma is with chemotherapy +/- bisphosphonates and surgical stabilization of fractures as needed.
Answer 5: Primary lymphoma of bone is treated with chemotherapy +/- local radiation therapy and fracture stabilization if needed.