Laparoscopic radical nephrectomy and minimally invasive surgery for kidney cancer

Modeling Neoplastic Growth in Renal Cell Carcinoma and Polycystic Kidney Disease

Renal cell carcinoma (RCC) and autosomal dominant polycystic kidney disease (ADPKD) share several characteristics, including neoplastic cell growth, kidney cysts, and limited therapeutics. As well, both exhibit impaired vasculature and compensatory VEGF activation of angiogenesis. The PI3K/AKT/mTOR and Ras/Raf/ERK pathways play important roles in regulating cystic and tumor cell proliferation and growth. Both RCC and ADPKD result in hypoxia, where HIF-α signaling is activated in response to oxygen deprivation. Primary cilia and altered cell metabolism may play a role in disease progression. Non-coding RNAs may regulate RCC carcinogenesis and ADPKD through their varied effects. Drosophila exhibits remarkable conservation of the pathways involved in RCC and ADPKD. Here, we review the progress towards understanding disease mechanisms, partially overlapping cellular and molecular dysfunctions in RCC and ADPKD and reflect on the potential for the agile Drosophila genetic model to accelerate discovery science, address unresolved mechanistic aspects of these diseases, and perform rapid pharmacological screens.

Return to work following laparoscopic-assisted resection or open resection for rectal cancer: Findings from AlaCaRT-Australasian Laparoscopic Cancer of the Rectum Trial

BACKGROUND

Maintaining employment for adults with cancer is important, however, little is known about the impact of surgery for rectal cancer on an individual's capacity to return to work (RTW). This study aimed to determine the impact of laparoscopic vs. open resection on RTW at 12 months.

METHODS

Analyses were undertaken among participants randomized in the Australian Laparoscopic Cancer of the Rectum Trial (ALaCaRT), with work status available at baseline (presurgery), and 12 months. Multivariable logistic regression, adjusted for sociodemographic and clinical characteristics estimated the effect of surgery on RTW in any capacity, or return to preoperative work status at 12 months.

RESULTS

About 228 of 449 (51%) surviving trial participants at 12 months completed work status questionnaires; mean age was 62 years, 66% males, 117 of these received laparoscopic resection (51%). Of 228, 120 were employed at baseline (90 full-time, 30 part-time). Overall RTW in 120 participants in paid work at baseline was 78% (84% laparoscopic, 70% open surgery). Those employed full-time were more likely to RTW at 12 months (OR, 3.55; 95% CI, 1.02-12.31). Those with distant metastases at baseline were less likely to RTW (OR, 0.07; 95% CI, <0.01-0.83). Laparoscopic surgery was associated with a higher rate of RTW but did not reach statistical significance (OR 2.88; 95% CI, 0.95-8.76).

CONCLUSIONS

Full-time work presurgery and the presence of metastatic disease predicts RTW status at 12 months. A laparoscopic-assisted surgical approach to rectal cancer may facilitate more patients to RTW, however, larger sample sizes are likely needed to confirm this result.

Survival among Black and White patients with renal cell carcinoma in an equal-access health care system

PURPOSE

Unequal access to health care may be a reason for shorter survival among Black patients with renal cell carcinoma (RCC) than among their White counterparts. No studies have investigated survival disparity among RCC patients in an equal-access health care delivery system. This study aimed to examine racial differences in survival among clear cell RCC patients in the Department of Defense's (DoD) Military Health System (MHS), which provides equal access to care to all persons.

METHODS

The study used the DoD's Automated Central Tumor Registry to identify 2056 White patients and 370 Black patients diagnosed with clear cell RCC between 1988 and 2004. The subjects were followed through 2007 with a median follow-up time of 4.8 years. Kaplan-Meier survival curves were compared and a Cox model was used to estimate the hazard ratios (HRs) associated with survival by race.

RESULTS

During follow-up, 1,027 White and 158 Black patients died. The Kaplan-Meier curves showed that Black patients had more favorable overall survival than did White patients (log rank p = 0.031). After adjustment for demographic, tumor, and treatment variables, the Cox model showed no statistically significant racial difference overall (adjusted HR 1.07, 95 % CI 0.90-1.28) or stratified by age, sex or tumor stage. However, among patients who did not undergo surgery, Black patients had poorer survival than White patients.

CONCLUSIONS

The lack of racial difference in survival among RCC patients in the MHS may be related to equal access to health care. Improved access could reduce the survival disparity among RCC patients in the general population.

Genetic variations in microRNA-related genes are associated with survival and recurrence in patients with renal cell carcinoma

We took a polygenic approach to evaluate the effects of 41 potentially functional single-nucleotide polymorphisms (SNPs) in microRNAs (miRNAs)-related genes on survival and recurrence among renal cell carcinoma (RCC) patients. During a median follow-up of 21.8 months, among 316 RCC patients, 64 died and 56 developed recurrence. In single-SNP analysis, we identified seven SNPs significantly associated with RCC survival and five SNPs with recurrence. The most significant associations were SNPs in GEMIN4 with the variant alleles of both rs7813 and rs910925 associated with 1.74-fold [95% confidence interval (CI) = 1.15-2.62] increased risk of death, whereas the variant allele of rs3744741 conferred a decreased risk of death [hazard ratio (HR) = 0.39; 95% CI = 0.19-0.77]. Several SNPs belonging to the pre-miRNA and were identified to be significantly associated with RCC recurrence. Haplotypes of DICER and DROSHA were also associated with altered patient survival and recurrence. More importantly, we observed cumulative effects of multiple SNPs on RCC survival. Compared with subjects carrying zero to two unfavorable genotypes, those carrying three to five and six and more unfavorable genotypes had an increased risk of death with a HR of 2.49 (95% CI = 1.24-5.00) and 6.66 (95% CI = 2.49-17.86), respectively, with significant dose-response trend (P for trend<0.001). As the first study of miRNA-related genetic polymorphisms on RCC clinical outcome, our results strongly suggested that miRNA-related SNPs may impact the recurrence and survival in RCC patients. Future investigation in larger populations and functional characterizations are necessary to validate these results.

Genome-wide profiling of chromosomal alterations in renal cell carcinoma using high-density single nucleotide polymorphism arrays

The identification of genetic aberrations may help understand the mechanisms of tumorigenesis and has important implications in diagnosis, prognosis and treatment. We applied Illumina's 317K high-density single nucleotide polymorphism (SNP) arrays to profile chromosomal aberrations in clear cell renal cell carcinoma (ccRCC) from 80 patients and analyzed the association of LOH/amplification events with clinicopathological characteristics and telomere length. The most common loss of heterozygosity (LOH) were 3p (69 cases) including 38 whole 3p arm losses, 30 large fragment LOH (spanning 3p21-36), and 1 interstitial LOH (spanning 3p12-14, 3p21-22, 3p24.1-24.2 and 3p24.3), followed by chromosome losses at 8p12-pter, 6q23.3-27, 14q24.1-qter, 9q32-qter, 10q22.3-qter, 9p13.3-pter, 4q28.3-qter and 13q12.1-21.1. We also found several smallest overlapping regions of LOH that contained tumor suppressor genes. One smallest LOH in 8p12 had a size of 0.29 Mb and only contained one gene (NRG1). The most frequent chromosome gains were at 5q (32 cases), including 10 whole 5q amplification, 21 large amplifications encompassing 5q32-ter and 1 focal amplification in 5q35.3 (0.42 Mb). The other common chromosome gains were 1q25.1-qter, 7q21.13-qter, 8q24.12-qter and whole 7p arm. Significant associations of LOH at 9p, 9q, 14q and 18q were observed with higher nuclear grade. Significant associations with tumor stage were observed for LOH at 14q, 18p and 21q. Finally, we found that tumors with LOH at 2q, 6p, 6q, 9p, 9q and 17p had significantly shorter telomere length than those without LOH. This is the first study to use Illumina's SNP-CGH array that provides a close estimate of the size and frequency of chromosome LOH and amplifications of ccRCC. The identified regions and genes may become diagnostic and prognostic biomarkers as well as potential targets of therapy.