Renal Medullary Carcinoma: a Report of the Current Literature

The New WHO Category of "Molecularly Defined Renal Carcinomas": Clinical and Diagnostic Features and Management Implications

The evolution of classification of renal tumors has been impacted since the turn of the millennium by rapid progress in histopathology, immunohistochemistry, and molecular genetics. Together, these features have enabled firm recognition of specific, classic types of renal cell carcinomas, such as clear cell renal cell carcinoma, that in current practice trigger histologic-type specific management and treatment protocols. Now, the fifth Edition World Health Classification's new category of "Molecularly defined renal carcinomas" changes the paradigm, defining a total of seven entities based specifically on their fundamental molecular underpinnings. These tumors, which include TFE3-rearranged, TFEB-altered, ELOC-mutated, fumarate hydratase-deficient, succinate dehydrogenase-deficient, ALK-rearranged, and SMARCB1-deficient renal medullary carcinoma, encompass a wide clinical and histopathologic phenotypic spectrum of tumors. Already, important management aspects are apparent for several of these entities, while emerging therapeutic angles are coming into view. A brief, clinically-oriented introduction of the entities in this new category, focusing on relevant diagnostic, molecular, and management aspects, is the subject of this review.

[SMARCB1-deficient renal medullary carcinoma with supra clavicular revealing location]

We report the case of a 14 year-old teenager who has SC hemoglobinosis and presented with a tumor syndrome with a retro-peritoneal mass, a supraclavicular lymph node and a mid-renal lesion. The microscopic examination revealed an undifferentiated tumor proliferation infiltrating the lymph node parenchyma. This tumor proliferation was INI1/SMARCB1-deficient, and expressed cytokeratins. Given the fact that the histopathological data showed an undifferentiated INI1-deficient carcinoma and that the patient has a kidney lesion and a sickle cell trait, the final diagnosis was lymph node metastasis of SMARCB1-deficient renal medullary carcinoma (OMS 2022).

Determination of birth prevalence of sickle cell disease using point of care test HemotypeSC™ at Rundu Hospital, Namibia

BACKGROUND

Sickle cell disease (SCD), a noncommunicable disease, has the greatest burden in sub-Saharan Africa. The majority of children (50-90%) with SCD die before their 5th birthday, with approximately 150,000-300,000 annual SCD child deaths in Africa. In developed countries, newborn screening (NBS) has been shown to improve the survival of children with sickle cell disease, with under5 childhood mortality reduced tenfold due to interventions performed before the development of complications. Point -of-care tests have been developed for resource limited settings to expand NBS. The aim of this study was to determine the birth prevalence of sickle cell disease in Namibia using the HemoTypeSC™ point-of-care test.

METHODS

A cross-sectional descriptive study was carried out at Rundu Intermediate Hospital in the Kavango East Region. Two hundred and two (202) well newborns within 72 h of birth were recruited for the study from 22 February to the 23th March 2023. Descriptive statistics were used to compute the haemoglobin types of the study participants.

RESULTS

The majority of the participants (n = 105, 52%) were females, and (n = 97,48%) were males. The median age of the participants was 23 h (Q1, Q3; 11; 33),) with an age range of 2-98 h. Sickle cell trait was present in 9.4% of the screened newborns, no homozygous disease was detected, and 90.6% had Hb AA.

CONCLUSIONS

This study is the first to measure HbS gene carriage at birth using HemotypeSC point-of-care testing in Namibia. There was a moderate prevalence of sickle cell traits but no SCD. This baseline study may provide the foundation for larger epidemiological surveys to map HbS gene carriage in Namibia to provide evidence for policy makers to fashion appropriate SCD newborn screening services.

Advanced renal cell carcinoma management: the Latin American Cooperative Oncology Group (LACOG) and the Latin American Renal Cancer Group (LARCG) consensus update

PURPOSE

Renal cell carcinoma is an aggressive disease with a high mortality rate. Management has drastically changed with the new era of immunotherapy, and novel strategies are being developed; however, identifying systemic treatments is still challenging. This paper presents an update of the expert panel consensus from the Latin American Cooperative Oncology Group and the Latin American Renal Cancer Group on advanced renal cell carcinoma management in Brazil.

METHODS

A panel of 34 oncologists and experts in renal cell carcinoma discussed and voted on the best options for managing advanced disease in Brazil, including systemic treatment of early and metastatic renal cell carcinoma as well as nonclear cell tumours. The results were compared with the literature and graded according to the level of evidence.

RESULTS

Adjuvant treatments benefit patients with a high risk of recurrence after surgery, and the agents used are pembrolizumab and sunitinib, with a preference for pembrolizumab. Neoadjuvant treatment is exceptional, even in initially unresectable cases. First-line treatment is mainly based on tyrosine kinase inhibitors (TKIs) and immune checkpoint inhibitors (ICIs); the choice of treatment is based on the International Metastatic Database Consortium (IMCD) risk score. Patients at favourable risk receive ICIs in combination with TKIs. Patients classified as intermediate or poor risk receive ICIs, without preference for ICI + ICIs or ICI + TKIs. Data on nonclear cell renal cancer treatment are limited. Active surveillance has a place in treating favourable-risk patients. Either denosumab or zoledronic acid can be used for treating metastatic bone disease.

CONCLUSION

Immunotherapy and targeted therapy are the standards of care for advanced disease. The utilization and sequencing of these therapeutic agents hinge upon individual risk scores and responses to previous treatments. This consensus reflects a commitment to informed decision-making, drawn from professional expertise and evidence in the medical literature.

Current status and future perspective of immunotherapy for renal cell carcinoma

In the last decade, the standard treatment for advanced renal cell carcinoma (RCC) has evolved, mainly driven by the development and approval of immune checkpoint inhibitors (ICIs). Currently, ICI monotherapy and ICI-based combinations with tyrosine kinase inhibitors and targeted therapies against mammalian target of rapamycin or vascular endothelial growth factor have become new standard treatments for first-line and subsequent-line therapies. ICIs play an important role as an adjuvant postoperative therapy, and this field is the subject of active research. Furthermore, ongoing randomized controlled trials are investigating the clinical value of more intense treatments by combining multiple effective treatments for RCC. Additionally, novel biomarkers for prognosis have been investigated. This study reviews the current evidence on immunotherapy as a treatment for RCC patients, randomized controlled trials, and ongoing studies including RCC patients and recent findings, and discusses future perspectives.

Clinico-pathological implications of the 2022 WHO Renal Cell Carcinoma classification

The new WHO classification of urogenital tumours published in 2022, contains significant revisions upon the previous 2016 version regarding Renal Cell Carcinoma (RCC). While the most common histotype remains almost untouched, some of the main novelties concerns papillary RCC and oncocytic neoplasms. The main change is the introduction of a new category of molecularly-defined RCC, which includes TFE3-rearranged RCC, TFEB-rearranged, and TFEB-amplified RCC, FH-deficient RCC, SDH-deficient RCC, ALK-rearranged RCC, ELOC (formerly TCEB1)-mutated RCC, SMARCB1 (INI1)-deficient RCC. In this paper we analyze the current knowledge on emerging entities and molecularly-defined RCC to assess whether the current pathological classification offers the oncologist the possibility of selecting more specific and personalized treatments, from both those currently available, as well as those that will soon be available.

Surgical and oncological management of renal medullary carcinoma in a young patient: a case report

Renal medullary carcinoma (RMC) is a rare form of renal cell carcinoma that has a poor prognosis. It is known to be associated with sickle cell trait or disease, although the exact underlying mechanisms are still unclear. The diagnosis is made through immunochemical staining for SMARCB1 (INI1). In this report, we present a case of a 31-year-old male patient with sickle cell trait who was diagnosed with stage III right RMC. Despite the poor prognosis, the patient survived for a remarkable duration of 37 months. Radiological assessment and follow-up were primarily performed using 18F-FDG PET/MRI. The patient underwent upfront cisplatin-based cytotoxic chemotherapy before surgical removal of the right kidney and retroperitoneal lymph node dissection. Identical adjuvant chemotherapy was administered post-surgery. Disease relapses were detected in the retroperitoneal lymph nodes; these were managed with chemotherapy and surgical rechallenges. We also discuss the oncological and surgical management of RMC, which currently relies on perioperative cytotoxic chemotherapy strategies, as there are no known alternative therapies that have been shown to be superior to date.

Molecular Characterization of the Tumor Microenvironment in Renal Medullary Carcinoma

Renal medullary carcinoma (RMC) is a highly aggressive disease associated with sickle hemoglobinopathies and universal loss of the tumor suppressor gene SMARCB1. RMC has a relatively low rate of incidence compared with other renal cell carcinomas (RCCs) that has hitherto made molecular profiling difficult. To probe this rare disease in detail we performed an in-depth characterization of the RMC tumor microenvironment using a combination of genomic, metabolic and single-cell RNA-sequencing experiments on tissue from a representative untreated RMC patient, complemented by retrospective analyses of archival tissue and existing published data. Our study of the tumor identifies a heterogenous population of malignant cell states originating from the thick ascending limb of the Loop of Henle within the renal medulla. Transformed RMC cells displayed the hallmarks of increased resistance to cell death by ferroptosis and proteotoxic stress driven by MYC-induced proliferative signals. Specifically, genomic characterization of RMC tumors provides substantiating evidence for the recently proposed dependence of SMARCB1-difficient cancers on proteostasis modulated by an intact CDKN2A-p53 pathway. We also provide evidence that increased cystine-mTORC-GPX4 signaling plays a role in protecting transformed RMC cells against ferroptosis. We further propose that RMC has an immune landscape comparable to that of untreated RCCs, including heterogenous expression of the immune ligand CD70 within a sub-population of tumor cells. The latter could provide an immune-modulatory role that serves as a viable candidate for therapeutic targeting.

Recent Advances in Renal Medullary Carcinoma

Renal medullary carcinoma (RMC) is a rare renal malignancy that has been associated with sickle hemoglobinopathies. RMC is aggressive, difficult to treat, and occurs primarily in adolescents and young adults of African ancestry. This cancer is driven by the loss of SMARCB1, a tumor suppressor seen in a number of primarily rare childhood cancers (e.g., rhabdoid tumor of the kidney and atypical teratoid rhabdoid tumor). Treatment options remain limited due in part to the limited knowledge of RMC biology. However, significant advances have been made in unraveling the biology of RMC, from genomics to therapeutic targets, over the past 5 years. In this review, we will present these advances and discuss what new questions exist in the field.

Parents' Experiences and Needs Regarding Infant Sickle Cell Trait Results

BACKGROUND AND OBJECTIVE

Sickle cell trait (SCT) has reproductive implications and can rarely cause health problems. SCT counseling improves parent knowledge but is infrequently received by children with SCT compared with children with cystic fibrosis carrier status. There are no national guidelines on SCT disclosure timing, frequency, or counseling content. Parents' experiences with SCT disclosure and counseling are poorly understood but could inform the development of guidelines. We explored parents' experiences with and desires for SCT disclosure and counseling for their infants with SCT identified via newborn screening.

METHODS

Parents of infants 2 to 12 months old with SCT were recruited through a state newborn screening program for semistructured interviews to explore their experiences with and desires for SCT disclosure and counseling. Inductive thematic analysis was conducted.

RESULTS

Sixteen interviews were completed from January to August 2020. Most parents reported that SCT disclosure occurred soon after birth, in person, and by the child's physician. Five themes were identified: parent knowledge before child's SCT disclosure, family planning, the dynamics of SCT disclosure and counseling, emotions and actions after SCT disclosure, and parent desires for the SCT disclosure and counseling process. Two primary parent desires were revealed. Parents want more information about SCT, particularly rare symptomatology, and they want SCT counseling repeated once the child approaches adolescence.

CONCLUSION

Parents report receiving their child's SCT diagnosis in the early newborn period from their child's doctor but indicate they receive incomplete information. Opportunities exist in primary care pediatrics to better align SCT disclosure timing and counseling content with parent desires.

Genitourinary Tract Tumors in Children: An Update

BACKGROUND

Genitourinary tract tumors in children are less common than in adults. Most of these tumors have different genetic backgrounds, clinical presentation, and oncologic behavior than their adult counterpart. As a result of low prevalence in children, some of the treatment approaches and recommendations are based on treatment experience in adult patients. However, thanks to scientific and technological development, survival rates have risen considerably.

OBJECTIVE

This paper presents a review of the principal features of the tumors involving the genitourinary tract in children and an update in genetic background, diagnosis, and treatment.

METHODS

A narrative review was performed on published literature about genitourinary tract tumors in pediatric patients. Papers presented in English and Spanish literature were reviewed. PubMed, Science Direct, and SciELO databases were used to collect information and present this article.

RESULTS

Kidney tumors are the most common type of genitourinary tumors in children. Among those, Wilms tumor represents the majority of cases and shows the successful work of clinical trial groups studying this tumor type. Other tumors involving the genitourinary tract in children include Rhabdomyosarcoma, Transitional cell carcinoma, Testicular, and Adrenal tumors.

CONCLUSION

Genitourinary tract tumors in children represent significant morbidity and economic burden, so awareness in early diagnosis represents improvement in treatment, clinical, and oncological outcomes.

Renal Medullary Carcinoma in an Adolescent With Unknown Sickle Cell Trait

Renal medullary carcinoma (RMC) is an aggressive and rare malignancy that usually presents in adolescents and young adults with sickle cell disease. Herein, we describe a case of a white male with an unknown sickle cell trait, who presented with left iliac fossa pain, without any other finding that suggested renal neoplasia.

Imaging findings were a renal mass of central location with caliectasis, renal hilar adenopathy, and paraaortic lymphadenopathy. Biopsy confirmed an RMC diagnosis.

RMC diagnosis requires clinical suspicion in sickle cell patients who present with pain and hematuria. Imaging shows a central mass, with an infiltrative appearance, frequently associated with calyx’s dilation and lymphadenopathy. Prognosis is poor in spite of the treatment.

Novel Patient Metastatic Pleural Effusion-Derived Xenograft Model of Renal Medullary Carcinoma Demonstrates Therapeutic Efficacy of Sunitinib

Background

Renal medullary carcinoma (RMC) is a rare but aggressive tumor often complicated by early lung metastasis with few treatment options and very poor outcomes. There are currently no verified RMC patient-derived xenograft (PDX) mouse models established from metastatic pleural effusion (PE) available to study RMC and evaluate new therapeutic options.

Methods

Renal tumor tissue and malignant PE cells from an RMC patient were successfully engrafted into 20 NOD.Cg-Prkdc^scid Il2rg^tm1Wjl/SzJ (NSG) mice. We evaluated the histopathological similarity of the renal tumor and PE PDXs with the original patient renal tumor and PE, respectively. We then evaluated the molecular integrity of the renal tumor PDXs between passages, as well as the PE PDX compared to two generations of renal tumor PDXs, by microarray analysis. The therapeutic efficacy of sunitinib and temsirolimus was tested in a serially-transplanted generation of 27 PE PDX mice.

Results

The pathologic characteristics of the patient renal tumor and patient PE were retained in the PDXs. Gene expression profiling revealed high concordance between the two generations of renal tumor PDXs (RMC-P0 vs. RMC-P1, r=0.865), as well as between the first generation PE PDX and each generation of the renal tumor PDX (PE-P0 vs. RMC-P0, r=0.919 and PE-P0 vs. RMC-P1, r=0.843). A low number (626) of differentially-expressed genes (DEGs) was seen between the first generation PE PDX and the first generation renal tumor PDX. In the PE-P1 xenograft, sunitinib significantly reduced tumor growth (p<0.001) and prolonged survival (p=0.004) compared to the vehicle control.

Conclusions

A metastatic PE-derived RMC PDX model was established and shown to maintain histologic features of the patient cancer. Molecular integrity of the PDX models was well maintained between renal tumor and PE PDX as well as between two successive renal tumor PDX generations. Using the PE PDX model, sunitinib demonstrated therapeutic efficacy for RMC. This model can serve as a foundation for future mechanistic and therapeutic studies for primary and metastatic RMC.

The Differential Diagnosis of Medullary-Based Renal Masses

CONTEXT.—

Renal malignancies can be divided into cortical- and medullary-based tumors, the latter of which classically infiltrate the renal parenchyma by extending between nonneoplastic structures. Although high-grade cortical tumors can rarely exhibit the same growth pattern, the infiltrative morphology should elicit a differential diagnosis to be considered in each case. However, these diagnoses can be challenging to distinguish, especially on small renal biopsy samples.

OBJECTIVE.—

To provide an overview of the clinical, gross, and microscopic findings; genetic and molecular alterations; and immunohistochemical evaluation of medullary-based renal tumors and other tumor types with overlapping morphologies and growth patterns.

DATA SOURCES.—

Literature review and personal observations were used to compile the information in this review.

CONCLUSIONS.—

Collecting duct carcinoma is a prototypical medullary-based tumor, and although diagnostic criteria exist, it remains a diagnosis of exclusion, especially with ancillary techniques aiding the recognition of established as well as more recently described neoplasms. Other medullary-based malignancies included in the differential diagnosis include renal medullary carcinoma/renal cell carcinoma unclassified with medullary phenotype, fumarate hydratase-deficient renal cell carcinoma, and upper tract urothelial carcinoma. Moreover, other rare entities should be excluded, including metastatic carcinoma, lymphoma, and melanoma. In addition to potential prognostic differences, accurate diagnoses can have important surgical and clinical management implications.

Tumors presenting in both pediatric and adult patients: a case-based review of pathology and imaging features for the radiologist

Various pathologic neoplasms present in both childhood and adulthood. Multiple environmental and genetic factors with different targets at different ages have been implicated in prior literature. These tumors include Multi-Locular Cystic Renal Tumors (MCRT), Adrenocortical Carcinomas, Paragangliomas, Hepatic Hemangiomas, and Medullary Renal Cell Carcinomas. The pertinent imaging, pathological, and clinical features of these select entities are discussed to assist the General and Pediatric Radiologist in accurate interpretation and treatment planning.

Desmoplastic Small Round Cell Tumor of the Kidney: Report of a Case, Literature Review, and Comprehensive Discussion of the Distinctive Morphologic, Immunohistochemical, and Molecular Features in the Differential Diagnosis of Small Round Cell Tumors Affecting the Kidney

Desmoplastic small round cell tumor (DSRCT) is a rare, highly aggressive neoplasm typically presenting with widespread involvement of the abdominopelvic peritoneum of adolescent males, usually without organ-based primary. Although it is believed to originate from the serous (mainly peritoneal) membranes, intracranial, sinonasal, intraosseous, and other soft tissue sites are also documented. A chromosomal translocation t(11:22)(p13;q12) signature that fuses EWSR1 and WT1 genes results in the production of a chimeric protein with transcriptional regulatory activity that drives oncogenesis. Integration of clinical, morphologic, immunohistochemical, and genetic data is necessary to arrive at the correct diagnosis, especially when the tumor arises in an atypical site. A 15-year-old male presented with hematuria and was found to have a large renal tumor associated with adrenal, liver, lung, and bone metastases. Histopathologic and immunophenotypic features were distinctive for DSRCT. This diagnosis was confirmed by means of fluorescence in situ hybridization and cytogenetic analysis, which documented the pathognomonic t(11;22) translocation, and by reverse transcription polymerase chain reaction on snap-frozen tissue, which revealed the EWSR1/WT1-specific chimeric transcript. Despite high-dose chemotherapy and radiation therapy targeted to a single T11 vertebral metastasis, the disease progressed, and the patient died 4 years after the diagnosis. A search of electronic databases for DSRCT yielded 16 cases of well-documented renal primaries out of around 1570 cases from all sites gathered from the global literature. Desmoplastic small round blue cell tumor and other primary renal tumors considered in the differential diagnosis with DSRCT are discussed.

Renal medullary carcinoma masquerading as renal infection: a case report

Background

Renal medullary carcinoma is a rare and aggressive tumor and often seen in young adults with sickle cell hemoglobinopathies.

Case presentation

We report a case of renal medullary carcinoma in a 29-year old male patient with an occupying renal lesion who presented with fever, flank pain and hematuria. The patient received intensive antibiotics treatment, but no improvement was seen. The symptoms disappeared after laparoscopic radical left nephrectomy. Postoperative pathological study showed that the mass was renal medullary carcinoma.

Conclusions

Our case suggests that renal medullary carcinoma should be considered in differential diagnoses of patients with occupying renal lesions who have fever of unknown origin.

Renal Medullary Carcinoma With Metastasis to the Temporal Fossa and Orbit

A 22-year-old Hispanic man with sickle cell trait presented with blurred vision, double vision, and pain with OD movement. MRI demonstrated an extra-axial mass centered around the temporal bone with extension into the middle cranial fossa and lateral aspect of the extra-conal right orbit, and mass effect on the lateral rectus muscle. Biopsy of the lesion was consistent with renal medullary carcinoma. CT chest/abdomen/pelvis confirmed a primary tumor in the right kidney. No additional metastases were found. Renal medullary carcinoma is a rare, highly aggressive malignancy, which almost exclusively affects young men of African descent with sickle cell trait or sickle cell disease. The authors present the second confirmed case of renal medullary carcinoma metastatic to the orbit, with ocular symptoms prior the typical presenting symptoms of flank pain and hematuria.Renal medullary carcinoma is a highly aggressive malignancy, most commonly seen in African American patients with sickle cell disease. Involvement of the orbit is rare and visual symptoms may precede systemic diagnosis.