Avelumab in metastatic collecting duct carcinoma of the kidney: a case report.

BACKGROUND: Collecting duct carcinoma (CDC) of the kidney is associated with an aggressive course, limited response to treatment, and poor prognosis. Platinum-based chemotherapy is currently recommended as the first-line treatment in patients with metastatic CDC. Accumulating evidence supports the use of immunotherapy with checkpoint inhibitors as second-line therapy. CASE PRESENTATION: In this case report, we describe the first case of avelumab administration due to disease progression during chemotherapy with gemcitabine and cisplatin in a Caucasian, 71-year-old man presenting with multiple metastases due to CDC of the kidney. The patient initially responded well to four cycles of chemotherapy and his performance status improved. After two additional chemotherapy cycles, the patient presented with new bone and liver metastases (mixed response to chemotherapy with an overall 6-month progression-free survival). We offered him avelumab as a second-line treatment in this setting. The patient received a total of three cycles of avelumab. The disease remained stable (no new metastases during treatment with avelumab), and the patient developed no complications. To alleviate his symptoms, radiation therapy for the bone metastases was decided. Despite successful radiation of the bone lesions and further improvement of symptoms, the patient developed hospital-acquired pneumonia and died approximately ten months after the initial diagnosis of CDC. CONCLUSIONS: Our findings suggest that the applied treatment modality with gemcitabine and cisplatin chemotherapy followed by avelumab was effective in terms of both progression-free survival and quality of life. Still, further studies assessing the use of avelumab in this setting are mandatory.

Molecular genetic findings in two cases of sarcomatoid carcinoma of the ureter: evidence for evolution from a common pluripotent progenitor cell?

The current World Health Organization classification recommends the usage of the term sarcomatoid carcinoma (SC) for all biphasic malignant neoplasms of the urinary tract exhibiting morphologic and/or immunohistochemical evidence of epithelial and mesenchymal differentiation. While most SC have been described in the urinary bladder, ureteral SC are extremely rare tumors. Here, we report on the clinical, morphological, and molecular biological findings of two cases in this unusual location. The genetic alterations investigated by comparative genomic hybridization in the epithelial and the mesenchymal component of both cases showed considerable but not complete overlap. Moreover, in spite of many morphological differences between the two cases, both cases shared some genetic gains and losses. Our findings are compatible with the concept that SC originates from a common pluripotent progenitor cell with a potential for epithelial and mesenchymal differentiation.