Update in collecting duct carcinoma: Current aspects of the clinical and molecular characterization of an orphan disease

Effective treatment of collecting duct carcinoma in a recipient of a kidney transplant: A case report

Collecting duct carcinoma (CDC) is a rare disease associated with a high mortality rate. The present study describes the case of a recipient of a kidney transplant with metastatic allograft CDC whose treatment was successful. The patient underwent nephrectomy, and chemotherapy with gemcitabine and cisplatin, while undergoing haemodialysis treatment and remained in remission after 6 years of follow-up. There is a lack of information about the treatment and clinical management of CDC; however, the combination of gemcitabine and cisplatin remains as first-line therapy. The challenge of this case was integrating chemotherapy sessions with dialysis therapy to maintain the effectiveness, tolerability and safety of the oncological treatment. In the present case report, the success of chemotherapy with gemcitabine and cisplatin was demonstrated in a metastatic renal allograft CDC in a patient with end-stage renal disease, with few side effects and no recurrence of the disease 6 years after the end of treatment.

Comprehensive molecular characterization of collecting duct carcinoma for therapeutic vulnerability

Collecting duct carcinoma (CDC) is an aggressive rare subtype of kidney cancer with unmet clinical needs. Little is known about its underlying molecular alterations and etiology, primarily due to its rarity, and lack of preclinical models. This study aims to comprehensively characterize molecular alterations in CDC and identify its therapeutic vulnerabilities. Through whole-exome and transcriptome sequencing, we identified KRAS hotspot mutations (G12A/D/V) in 3/13 (23%) of the patients, in addition to known TP53, NF2 mutations. 3/13 (23%) patients carried a mutational signature (SBS22) caused by aristolochic acid (AA) exposures, known to be more prevalent in Asia, highlighting a geologically specific disease etiology. We further discovered that cell cycle-related pathways were the most predominantly dysregulated pathways. Our drug screening with our newly established CDC preclinical models identified a CDK9 inhibitor LDC000067 that specifically inhibited CDC tumor growth and prolonged survival. Our study not only improved our understanding of oncogenic molecular alterations of Asian CDC, but also identified cell-cycle machinery as a therapeutic vulnerability, laying the foundation for clinical trials to treat patients with such aggressive cancer.

Rare type of Bellini Duct Carcinoma in a Patient With Cacchi-Ricci Disease: A Case Report and Mini-Review

Medullary sponge kidney (MSK) is an uncommon kidney malformation, characterized by cystic dilatation of the precalyceal papillary collecting ducts. Urography and computed tomography scan represent the gold standard to detect this congenital disorder. A clear diagnosis is not always feasible, especially in the presence of a concomitant renal mass, which in turn can be difficult to detect in MSK patients. When conventional imaging is inconclusive, a renal biopsy can be considered in doubtful cases. Here, we report a unique case of a Bellini duct carcinoma in a patient with MSK and we review the literature on this complex condition.

Renal mass biopsy - a practical and clinicopathologically relevant approach to diagnosis

Advancements in imaging modalities have increased the frequency of renal mass discovery. Imaging has typically been considered sufficient to guide management for a large proportion of these tumours, but renal mass biopsies (RMBs) have an increasing role in determining malignancy and can be a valuable tool for preventing unnecessary surgery in patients with benign tumours. A structured approach should be used to help to navigate the expanding repertoire of renal tumours, many of which are molecularly defined. In terms of tumour subtyping, the pathologist's strategy should focus on stratifying patients into clinically different prognostic groups according to our current knowledge of tumour behaviour, including benign, low-grade or indolent, intermediate malignant or highly aggressive. Crucial pathological features and morphological mimicry of tumours can alter the tumour's prognostic group. Thus, pathologists and urologists can use RMB to select patients with tumours at a reduced risk of progression, which can be safely managed with active surveillance within a tailored imaging schedule, versus tumours for which ablation or surgical intervention is indicated. RMB is also crucial in the oncological setting to distinguish between different high-grade tumours and guide tailored management strategies.

A curious case: Concurrent collecting duct renal cell carcinoma and upper tract urothelial carcinoma

A 71-year-old male presented to Urology with three weeks of overt haematuria and increasing lethargy. Contrast-enhanced CT scans revealed an 8 × 6cm partially exophytic lesion in the left kidney's upper pole, extending beyond the capsule and invading the superior cortical vein, accompanied by abnormal retrocrural lymph nodes. Signs of paraneoplastic syndrome prompted a left radical nephrectomy for symptom relief. Histological analysis identified high-grade collecting duct renal carcinoma and invasive urothelial cell carcinoma. Post-surgery, he was referred for oncological treatment but passed away within two months of the initial diagnosis.

Urine cytology in the detection of renal cell carcinomas - a territory-wide multi-institutional retrospective review of more than 2 decades

INTRODUCTION

Compared with urothelial lesions of the upper urinary tract, the diagnostic performance of urine cytology in detection of renal cell carcinomas is underreported. This study aims to establish the role of urine cytology in the assessment of renal carcinomas by a multi-institute review of urine cytology from nephrectomy confirmed renal cell carcinomas, referenced against renal urothelial and squamous cell carcinomas.

METHODS

Records of nephrectomy performed from the 1990s to 2020s at three hospitals were retrieved and matched to urine cytology specimens collected within 1 year prior. Patient demographics, specimen descriptors, and histology and staging parameters were reviewed and compared against cytologic diagnoses.

RESULTS

There were 1147 cases of urine cytology matched with renal cell carcinomas, with 666 renal urothelial/squamous carcinomas for comparison. The detection rate for urothelial/squamous (atypia or above [C3+]: 63.1%; suspicious or above [C4+]: 24.0%) were higher than renal cell carcinoma (C3+: 13.1%; C4+: 1.5%) (p < 0.001). The positive rate for upper tract urine exceeded other collection methods at 45.0% (C3+) and 10.0% (C4+) (p < .01). Other factors associated with increased positive rates were male sex, collecting duct carcinoma histology, nuclear grade, and renal/sinus involvement (p < .05). Multivariate analysis revealed additional positive correlations with presence of sarcomatoid tumor cells, lymphovascular invasion, and perinephric fat involvement (p < .05). Larger lesion size and higher urine volume did not improve detection rates (p < .05).

CONCLUSIONS

The detection rate of renal cell carcinomas is suboptimal compared with urothelial carcinomas, although urine samples collected from cystoscopy or percutaneous nephrostomy significantly outperformed voided urine specimens.

A rare case of collecting duct renal cell carcinoma

Collecting duct carcinoma is an exceptionally rare and aggressive form of renal cell carcinoma (RCC), representing between 0.4 and 1.8% of RCC cases. The most commonly affected demographic are young African-American males. Here, we present a rare case of collecting duct RCC in a 22 year-old Caucasian female with final pathological staging of pT1aN1 who underwent robot-assisted right radical nephrectomy, with peri-hilar and para-aortic lymph node dissection. Given her node-positivity, adjunctive treatment is discussed.

Systemic Treatment for Advanced and Metastatic Non-Clear Cell Renal Cell Carcinoma: Examining Modern Therapeutic Strategies for a Notoriously Challenging Malignancy

Non-clear cell renal cell carcinoma (nccRCC) is a heterogeneous group of malignancies that represents 25% of renal cell carcinoma (RCC) cases. Treatment for non-clear cell histologies is mostly based on evidence from small phase II clinical trials or extrapolated from successful therapies in clear cell RCC because of the low incidence of non-clear cell pathology. Advances in genomic profiling have improved clinicians' understanding of molecular targets for nccRCC, such as altered mesenchymal epithelial transition (MET) gene status and fumarate hydratase (FH) gene inactivation, but patient outcomes remain poor and optimal management of this disease remains unclear. This review assesses outcomes by histologic subtype from 27 prospective and 13 ongoing clinical trials to identify therapeutic strategies for advanced or metastatic nccRCC. Vascular endothelial growth factor tyrosine kinase inhibitors (TKI), such as sunitinib, and mammalian target of rapamycin (mTOR) inhibitors, such as everolimus, have demonstrated efficacy and remain viable treatment options, with a preference for sunitinib. However, everolimus is preferred in patients with chromophobe RCC because folliculin (FLCN) gene mutations upregulate the mTOR pathway. Novel TKIs, such as cabozantinib, show improved outcomes in patients with papillary RCC because of targeted MET inhibition. Platinum-based chemotherapy continues to be the recommended treatment strategy for collecting duct and medullary RCC. Clinically meaningful antitumor activity has been observed across all non-clear cell histologies for immune checkpoint inhibitors, such as nivolumab, pembrolizumab, and ipilimumab. Ongoing trials are evaluating novel tyrosine kinase inhibitor and immunotherapy combination regimens, with an emphasis on the promising MET-inhibitor cabozantinib and pembrolizumab plus lenvatinib.

SEOM SOGUG clinical guideline for treatment of kidney cancer (2022)

Renal cancer is the seventh most common cancer in men and the tenth in women. The aim of this article is to review the diagnosis, treatment, and follow-up of renal carcinoma accompanied by recommendations with new evidence and treatment algorithms. A new pathologic classification of RCC by the World Health Organization (WHO) was published in 2022 and this classification would be considered a "bridge" to a future molecular classification. For patients with localized disease, surgery is the treatment of choice with nephron-sparing surgery recommended when feasible. Adjuvant treatment with pembrolizumab is an option for intermediate-or high-risk cases, as well as patients after complete resection of metastatic disease. More data are needed in the future, including positive overall survival data. Clinical prognostic classification, preferably IMDC, should be used for treatment decision making in mRCC. Cytoreductive nephrectomy should not be deemed mandatory in individuals with intermediate-poor IMDC/MSKCC risk who require systemic therapy. Metastasectomy can be contemplated in selected subjects with a limited number of metastases or long metachronous disease-free interval. For the population of patients with metastatic ccRCC as a whole, the combination of pembrolizumab-axitinib, nivolumab-cabozantinib, or pembrolizumab-lenvatinib can be considered as the first option based on the benefit obtained in OS versus sunitinib. In cases that have an intermediate IMDC and poor prognosis, the combination of ipilimumab and nivolumab has demonstrated superior OS compared to sunitinib. As for individuals with advanced RCC previously treated with one or two antiangiogenic tyrosine-kinase inhibitors, nivolumab and cabozantinib are the options of choice. When there is progression following initial immunotherapy-based treatment, we recommend treatment with an antiangiogenic tyrosine-kinase inhibitor. While no clear sequence can be advocated, medical oncologists and patients should be aware of the recent advances and new strategies that improve survival and quality of life in the setting of metastatic RC.

PI3K/AKT/mTOR Dysregulation and Reprogramming Metabolic Pathways in Renal Cancer: Crosstalk with the VHL/HIF Axis

Renal cell carcinoma (RCC) represents 85-95% of kidney cancers and is the most frequent type of renal cancer in adult patients. It accounts for 3% of all cancer cases and is in 7th place among the most frequent histological types of cancer. Clear cell renal cell carcinoma (ccRCC), accounts for 75% of RCCs and has the most kidney cancer-related deaths. One-third of the patients with ccRCC develop metastases. Renal cancer presents cellular alterations in sugars, lipids, amino acids, and nucleic acid metabolism. RCC is characterized by several metabolic dysregulations including oxygen sensing (VHL/HIF pathway), glucose transporters (GLUT 1 and GLUT 4) energy sensing, and energy nutrient sensing cascade. Metabolic reprogramming represents an important characteristic of the cancer cells to survive in nutrient and oxygen-deprived environments, to proliferate and metastasize in different body sites. The phosphoinositide 3-kinase-AKT-mammalian target of the rapamycin (PI3K/AKT/mTOR) signaling pathway is usually dysregulated in various cancer types including renal cancer. This molecular pathway is frequently correlated with tumor growth and survival. The main aim of this review is to present renal cancer types, dysregulation of PI3K/AKT/mTOR signaling pathway members, crosstalk with VHL/HIF axis, and carbohydrates, lipids, and amino acid alterations.