Genomic features of renal cell carcinoma developed during end-stage renal disease and dialysis

Acquired Cystic Disease-Associated Renal Cell Carcinoma: A Systematic Review and Meta-analysis

Acquired cystic disease-associated renal cell carcinoma (ACD-RCC) is a common subtype of renal cell carcinoma (RCC) in end-stage renal disease (ESRD) patients. The current systematic review and meta-analysis was performed to evaluate the clinicopathological, and genetic characteristics of patients with ACD-RCC. A systematic search on three electronic databases including the Pubmed, Scopus, and Web of Science databases were performed until December 31, 2022. A meta-analysis was performed following the PRISMA 2020 Guidelines. Of 888 identified articles, full-text screening in 69 articles, there were 26 articles analyzed, with a total of 2314 tumors in 2199 patients, including 418 ACD-RCC tumors in 363 patients, 1340 clear cell RCC (ccRCC) tumors, 308 papillary RCC (pRCC) tumors. Most ACD-RCC patients were male (80.2%). All the ACD-RCC patients underwent prior dialysis with 148.2 months of mean dialysis duration. There were 8.7%, 3.4%, and 5.8% tumors at the T3-4 stage, N1 stage, and M1 stage, respectively. The mean overall survival of ACD-RCC patients was 39.6 months (95% CI, 26.6-52.5). Compared to ccRCC and pRCC, ACD-RCC patients had a longer duration of dialysis (MD: 103.5 and 31.77 months, respectively; 95% CI: [75.48; 131.53] and [0.95; 62.58], respectively), and a higher rate of multifocal tumors (MD: 3.46 and 2.45 tumors, respectively; 95% CI [1.71; 6.98] and [1.26; 4.79], respectively). Regarding genetic characteristics, chromosomes 3 and 16 were the 2 most frequent chromosomal aberrations. The missense mutation in KMT2C (25%) and TSC2 (18.75%) were the 2 most common gene mutations in ACD-RCC. In conclusion, the ACD-RCC subtype exhibited several distinct clinicopathological and genetic characteristics compared to others RCC subtypes. Further researchs are needed to assess the survival outcome and the genetic characteristics of this subtype.

Renal cell carcinoma outcomes in end-stage renal disease: A 40-year study from two Japanese institutions

OBJECTIVES

The objective of the study was to analyze the outcomes of patients with renal cell carcinoma (RCC) arising in end-stage renal disease (ESRD) over a 40-year span.

METHODS

We retrospectively evaluated data of patients with ESRD-RCC diagnosed between 1979 and 2020 at two institutions. We assessed changes in stage, surgical approaches, and cancer-specific survival (CSS) following nephrectomy according to era between ESRD-RCC and sporadic RCC. Furthermore, perioperative outcomes in patients with ESRD-RCC were compared between laparoscopic and open surgery.

RESULTS

Patients with ESRD-RCC (n = 549) were diagnosed at an earlier stage (p = 0.0276), and the ratio of laparoscopic nephrectomy was increased (p < 0.0001) according to eras. Since 2000 (i.e., after implementation of laparoscopic nephrectomy), patients with ESRD-RCC (n = 305) had significantly shorter CSS (p = 0.0063) after nephrectomy than sporadic RCC (n = 2732). After adjustment by multivariate analysis and propensity score matching, ESRD status was independently associated with shorter CSS (p = 0.0055 and p = 0.0473, respectively). Improved CSS in sporadic RCC (p < 0.0001), but not ESRD-RCC (p = 0.904), according to era contributed to this difference. Laparoscopic nephrectomy showed favorable outcomes, including shorter surgery time, lower estimated bleeding volumes, transfusion rates, and readmission rates, and shorter postoperative hospitalization than open nephrectomy (p < 0.05).

CONCLUSIONS

Advances in diagnostic and treatment modalities potentially enable early diagnosis and minimally invasive surgery for patients with ESRD-RCC. As ESRD-RCC may not present indolently, careful post-operative monitoring is needed.

Mitochondrial DNA Variants at Low-Level Heteroplasmy and Decreased Copy Numbers in Chronic Kidney Disease (CKD) Tissues with Kidney Cancer

The human mitochondrial genome (mtDNA) is a circular DNA molecule with a length of 16.6 kb, which contains a total of 37 genes. Somatic mtDNA mutations accumulate with age and environmental exposure, and some types of mtDNA variants may play a role in carcinogenesis. Recent studies observed mtDNA variants not only in kidney tumors but also in adjacent kidney tissues, and mtDNA dysfunction results in kidney injury, including chronic kidney disease (CKD). To investigate whether a relationship exists between heteroplasmic mtDNA variants and kidney function, we performed ultra-deep sequencing (30,000×) based on long-range PCR of DNA from 77 non-tumor kidney tissues of kidney cancer patients with CKD (stages G1 to G5). In total, this analysis detected 697 single-nucleotide variants (SNVs) and 504 indels as heteroplasmic (0.5% ≤ variant allele frequency (VAF) < 95%), and the total number of detected SNVs/indels did not differ between CKD stages. However, the number of deleterious low-level heteroplasmic variants (pathogenic missense, nonsense, frameshift and tRNA) significantly increased with CKD progression (p < 0.01). In addition, mtDNA copy numbers (mtDNA-CNs) decreased with CKD progression (p < 0.001). This study demonstrates that mtDNA damage, which affects mitochondrial genes, may be involved in reductions in mitochondrial mass and associated with CKD progression and kidney dysfunction.