Current Trends and Challenges of Microbiome Research in Bladder Cancer.

PURPOSE OF THE REVIEW: Microbiome research has provided valuable insights into the associations between microbial communities and bladder cancer. However, this field faces significant challenges that hinder the interpretation, generalization, and translation of findings into clinical practice. This review aims to elucidate these challenges and highlight the importance of addressing them for the advancement of microbiome research in bladder cancer. RECENT FINDINGS: Recent findings underscore the complexities involved in microbiome research, particularly in the context of bladder cancer. Challenges include low microbial biomass in urine samples, potential contamination issues during collection and processing, variability in sequencing methods and primer selection, and the difficulty of establishing causality between microbiota and bladder cancer. Studies have shown the impact of sample storage conditions and DNA isolation kits on microbiome analysis, emphasizing the need for standardization. Additionally, variations in urine collection methods can introduce contamination and affect results. The choice of 16S rRNA gene amplicon sequencing or shotgun metagenomic sequencing introduces technical challenges, including primer selection and sequencing read length. Establishing causality between the microbiota and bladder cancer requires experimental methods like fecal microbiota transplantation and human microbiota-associated murine models, which face their own set of challenges. Translating microbiome research into therapeutic applications is hindered by methodological variability, incomplete understanding of bioactive molecules, imperfect animal models, and the inherent heterogeneity of microbiome communities among individuals. Microbiome research in bladder cancer presents significant challenges stemming from technical and conceptual complexities. Addressing these challenges through standardization, improved experimental models, and advanced analytical approaches is essential for advancing our understanding of the microbiome's role in bladder cancer and its potential clinical applications. Achieving this goal can lead to improved patient outcomes and novel therapeutic strategies in the future.

Genomic Evolution of Oligometastatic Clear Cell Renal Cell Carcinoma Presenting Two Decades Following Radical Nephrectomy.

Metachronous oligometastatic clear cell renal cell carcinoma may take many years before becoming clinically apparent. Herein we report regional lymph node recurrence of clear cell renal cell carcinoma more than two decades following radical nephrectomy. Chromosomal microarray analysis demonstrated multiple chromosomal alterations, including 3pq deletion shared by the original and recurrent tumors, and 17p deletion containing the TP53 gene present only in the latter. Sequencing of 1550 genes revealed mutations of VHL in both the primary and metastasis and BAP1 only in the metastatic lesion. These findings genetically link the original and recurrent tumors and suggest that VHL, TP53, and BAP1 alterations played an evolutionary role in recurrence decades after initial resection.

A sheep in wolf's clothing; a case of renal leiomyoma masquerading as hereditary leiomyomatosis and renal cell carcinoma.

Active surveillance has become a standard of care for the management of small renal masses. Decision to transition from surveillance to intervention relies on several factors including growth kinetics, histologic grade on biopsy and patient comorbidities. Management of renal masses in pregnancy presents a unique change when clinical triggers must be weighed with risk to fetus. We present the case of a third trimester patient with an enlarging and enhancing renal mass managed with robotic assisted laparoscopic partial nephrectomy. Histologic analysis was consistent with renal leiomyoma. Renal leiomyomas are a rare benign mesenchymal tumor influenced by changes in progesterone-estrogen axis.

Pathological and Clinical Outcomes in a Large Surveillance and Intervention Cohort of Radiographically Cystic Renal Masses.

PURPOSE: We evaluated oncologic risks in a large cohort of patients with radiographic cystic renal masses who underwent active surveillance or intervention. MATERIALS AND METHODS: A single-institutional database of 4,340 kidney lesions managed with either active surveillance or intervention between 2000-2020 was queried for radiographically cystic renal masses. Association of radiographic tumor characteristics and high-grade pathology was evaluated. RESULTS: We identified 387 radiographically confirmed cystic lesions in 367 patients. Of these, 247 were resected (n=240) or ablated (n=7; n=247, 203 immediate vs 44 delayed intervention). Pathologically, 23% (n=56) demonstrated high-grade pathology. Cystic features were explicitly described by pathology in only 18% (n=33) of all lesions and in 7% (n=4) of high-grade lesions. Of the intervention cohort, African American race, male gender, and Bosniak score were associated with high-grade pathology (P < .05). On active surveillance (n=184), Bosniak IV lesions demonstrated faster growth rates than IIF and III lesions (2.7 vs 0.6 and 0.5 mm/y, P ≤ .001); however, growth rates were not associated with high-grade pathology (P = .5). No difference in cancer-specific survival was identified when comparing intervention vs active surveillance at 5 years (99% vs 100%, P = .2). No difference in recurrence was observed between immediate intervention vs delayed intervention (P > .9). CONCLUSIONS: A disconnect between "cystic" designation on imaging and pathology exists for renal lesions. Over 80% of radiographic Bosniak cystic lesions are not described as "cystic" on pathology reports. More than 1 in 5 resected cystic renal lesions demonstrated high-grade disease. Despite this finding, judiciously managed active surveillance ± delayed intervention is a safe and effective management option for most radiographic cystic renal masses.