Hepatic and lung methotrexate-associated polymorphic lymphoproliferative disorders arising during postoperative follow-up of renal cell carcinoma: a case report.

INTRODUCTION: Methotrexate induces lymphoproliferative disorders on rare occasions; however, its pathogenesis remains unknown. A clinical diagnosis based on imaging studies alone is often difficult. CASE PRESENTATION: A 57-year-old Japanese woman was referred to our department for the evaluation of multiple lung and hepatic nodules that developed during methotrexate treatment for rheumatoid arthritis. Since she had a history of nephrectomy for localized renal cell carcinoma, multiple lung and hepatic metastases were initially considered. However, pathological diagnosis of the lung nodules (needle biopsy) revealed methotrexate-associated polymorphic-type lymphoproliferative disorders. After methotrexate discontinuation, continuous smooth shrinkage of the lung and liver lymphoproliferative disorders was observed. CONCLUSION: Methotrexate-associated lymphoproliferative disorders should be considered in the event of newly appearing neoplastic lesions, even during follow-up for renal cell carcinoma, if methotrexate is being administered.

Epithelioid Angiomyolipoma with Tumor Thrombus into Inferior Vena Cava Presurgically Treated with Combination Therapy of Pembrolizumab and Axitinib: A Case Report.

Epithelioid angiomyolipoma (EAML) is a rare variant of AML with malignant potential. It is occasionally difficult to distinguish EAML from renal cell carcinoma (RCC) on imaging. A 72-year-old woman was admitted to our hospital for the treatment of a left renal tumor with relatively high blood flow and a tumor thrombus extending to the inferior vena cava, suggesting RCC. The patient underwent presurgical combination therapy with axitinib and pembrolizumab. This treatment significantly shortened the thrombus, and radical nephrectomy was performed. The pathological findings were compatible with EAML, and the treatment effects were observed. We report a case treated pre-surgically with a combined therapy of pembrolizumab and axitinib, with a favorable response as a treatment option for EAML.