Quantitative detection of RASSF1A DNA promoter methylation in tumors and serum of patients with serous epithelial ovarian cancer

OBJECTIVE

Detection of cell free tumor-specific DNA methylation has been proposed as a potentially useful noninvasive mechanism to detect malignancies, including ovarian cancer, and to monitor response to treatment. However, there are few easily implemented quantitative approaches available for DNA methylation analysis. Our objectives were to develop an absolute quantitative method for detection of DNA methylation using RASSF1A, a known target of promoter methylation in ovarian cancer, and test the ability to detect RASSF1A methylation in tumors and serum specimens of women with ovarian cancer.

METHODS

Bisulfite modified DNAs were subjected to real time PCR using nondiscriminatory PCR primers and a probe with sequence containing a single CpG site, theoretically able to capture the methylation status of that CpG for every allele within a given specimen. Input DNA was normalized to ACTB levels detected simultaneously by assay multiplexing. Methylation levels were established by comparison to results obtained from universally methylated DNA.

RESULTS

The assay was able to detect one methylated RASSF1A allele in 100,000 unmethylated alleles. RASSF1A was methylated in 54 of 106 (51%) invasive serous ovarian cancers analyzed and methylation status was concordant in 20/20 matched preoperative serum-tumor pairs. Serial serum specimens taken over the course of treatment for 8 of 9 patients showed fluctuations in RASSF1A methylation concomitant with disease status.

CONCLUSIONS

This novel assay provides a real-time PCR-based method for absolute quantitation of DNA methylation. Our results support feasibility of monitoring RASSF1A methylation from serum samples taken over the course of treatment from women with ovarian cancer.

Adverse events associated with laparoscopy vs laparotomy in the treatment of endometrial cancer

OBJECTIVE

The objective of the study was to compare adverse event rates between laparoscopic vs open surgery for endometrial cancer.

STUDY DESIGN

This was a retrospective cohort study comparing 107 women who underwent laparoscopy with 269 age- and body mass index-matched women who underwent laparotomy for treatment of endometrial cancer.

RESULTS

Adverse event rates were similar between cohorts (37% laparoscopy vs 43% laparotomy, P=.248). Laparotomies had higher rates of cellulitis (16% vs 7%, P=.018) and open wound infection (9% vs 2%, P=.02), whereas laparoscopy had higher rates of sensory peripheral nerve deficit (5% vs 0%, P=.008) and lymphedema (7% vs 1%, P=.003). Laparoscopy was associated with longer mean operating room times but with shorter hospital stays and lower mean blood loss.

CONCLUSION

Laparoscopy was associated with decreased rates of surgical site infections but had an increased risk of peripheral sensory nerve deficits and lymphedema when compared with laparotomy.

Surgical outcomes in gynecologic oncology in the era of robotics: analysis of first 1000 cases

OBJECTIVE

We sought to examine outcomes in an expanding robotic surgery (RS) program.

STUDY DESIGN

In all, 1000 women underwent RS from May 2006 through December 2009. We analyzed patient characteristics and outcomes. A total of 377 women undergoing RS for endometrial cancer staging (ECS) were compared with the historical data of 131 undergoing open ECS.

RESULTS

For the entire RS cohort of 1000, the conversion rate was 2.9%. Body mass index increased over 3 time intervals: T1 = 26.2, T2 = 29.5, T3 = 30.1 (T1:T2, P = .01; T1:T3, P = .0001; T2:T3, P = .037). Increasing body mass index was not associated with increased major complications: T1 = 8.7%, T2 = 4.3%, T3 = 5.7%. In the ECS cohort, as compared with open ECS, women undergoing RS had lower blood loss (46.9 vs 197.6 mL, P < .0001), shorter hospitalization (1.4 vs 5.3 days, P < .0001), fewer major complications (6.4% vs 20.6%, P < .0001), with higher lymph node counts (15.5 vs 13.1, P = .007).

CONCLUSION

RS is associated with favorable morbidity and conversion rates in an unselected cohort. Compared to laparotomy, robotic ECS results in improved outcomes.