Metastatic Renal Medullary Carcinoma Treated With Immune Checkpoint Inhibitor: Case Report and Literature Review

[Collecting duct carcinoma and renal medullary carcinoma in the age of new therapies]

Collecting duct carcinoma (also known as Bellini tumour) and renal medullary carcinoma are two extremely rare and aggressive renal cancers. They are both less responsive to conventional treatments used in clear cell renal carcinoma. There are very few studies evaluating their optimal management and currently, at the metastatic stage, polychemotherapy based on platinum salts remains the most widely used. The emergence of new treatments such as anti-angiogenic TKIs, immunotherapy or treatments targeting specific genetic abnormalities, opens up a new field of possibilities in the management of these cancers. The evaluation of the response to these treatments is therefore essential. In this article, we will review the status of their management and the various studies that have evaluated recent treatments in these two cancers.

Checkpoint Immunotherapy in Pediatrics: Here, Gone, and Back Again

The role of immune checkpoint inhibitors (ICIs) in the treatment of pediatric cancers continues to evolve. Such therapies function by augmenting existing antitumor T-cell responses that have been rendered ineffective by inhibitory pathways. Although ICIs have proven highly effective for adult cancers, initial phase I/II clinical trials using single-agent ICIs against unselected pediatric cancers have been overall disappointing. With the exception of pediatric classic Hodgkin lymphoma, responses to ICIs have been infrequent, likely stemming from an inherent difference in the immunogenicity of childhood cancers, which, on average, have far fewer neoantigens than adult cancers. Recently, however, hope has reemerged that certain subsets of children with cancer may benefit from ICI therapies. In preliminary studies, patients with both pediatric hypermutated and SMARCB1-deficient cancers have had impressive responses to ICI therapies, likely as a result of underlying biologies that enhance neoantigen expression and tumoral inflammation. Dedicated trials are ongoing to fully evaluate the efficacy of ICIs for patients with these subsets of pediatric cancer.

Renal Medullary Carcinoma: a Report of the Current Literature

PURPOSE OF THE REVIEW

We present an updated report of renal medullary carcinoma (RMC), a rare and aggressive condition.

RECENT FINDINGS

There is a majority of male patients, of African descent, in the second or third decade of life. In differential diagnosis, other tumors, such as malignant rhabdoid tumor (MRT), vinculin-anaplastic lymphoma kinase (VCL-ALK) translocation renal cell carcinoma, and collecting duct carcinoma, may present difficulties. Abnormalities of tumor suppressor gene SMARCB1 have been found in RMC. Reported symptoms were hematuria, pain, weight loss, respiratory distress, palpable mass, cough, and fever. Most patients present with metastases at diagnosis. There is no definite recommended treatment, and protocols are extrapolated from other malignancies, with nephrectomy and systemic therapies being most frequently used. Response to treatment and prognosis remain very poor. RMC is a rare and aggressive tumor. Definitive diagnosis requires histological assessment and the presence of sickle-cell hemoglobinopathies.