While initial surgical debulking is the goal, there are circumstances when a different approach may be indicated. Vergote et al. conducted a prospective randomized trial of 670 women with advanced ovarian cancer. In this study, neoadjuvant chemotherapy followed by interval debulking was not inferior to primary debulking followed by chemotherapy with regards to progression-free survival and overall survival. However, initial surgery was associated with increased surgical complications and perioperative mortality as compared with interval surgery. Therefore, in women who are not felt to be candidates for optimal cytoreduction, neoadjuvant chemotherapy followed by interval surgery may be an appropriate treatment strategy (N Engl J Med. 2010 Sep 2;363[10]:943-53.).
Courtesy Wikimedia Commons/James Heilman, MD/CC-BY-SA-3.0
There have been several notable advances and a series of randomized trials – predominately conducted by the GOG – that have resulted in improved overall survival and progression-free interval in women with ovarian cancer. However, none are as significant as the discovery of paclitaxel and platinum-based chemotherapy (cisplatin and carboplatin).
In 1962, samples of the Pacific Yew’s bark were collected and, 2 years later, the extracts from this bark were found to have cytotoxic activity. There were initial difficulties suspending the drug in solution; however, ultimately a formulation in ethanol, cremophor, and saline was found to be effective. In 1984, the National Cancer Institute began clinical trials of paclitaxel and it was found to be highly effective in ovarian cancer. In 1992, it was approved for the treatment of ovarian cancer.
Cisplatin was approved in 1978. Carboplatin entered clinical trials in 1982 and was approved for women with recurrent ovarian cancer in 1989.
There were a series of trials beginning in the late 1980s that established the role of platinum agents and led us to GOG 111. This trial evaluated cisplatin with either cyclophosphamide or paclitaxel. The paclitaxel combination was superior and in 2003 two trials were published that solidified carboplatin and paclitaxel as the cornerstone in the treatment of women with ovarian cancer (J Clin Oncol. 2003 Sep 1;21[17]:3194-200; J Natl Cancer Inst. 2003 Sep 3;95[17]:1320-9).
What has most recently been debated is the route and schedule for both paclitaxel and the platinum agents. In January 2006, the National Cancer Institute released a Clinical Announcement regarding the role of intraperitoneal (IP) chemotherapy for the treatment of women with optimally debulked ovarian cancer. Of the six trials included in the announcement, four trials showed a benefit for progression-free survival and five studies showed an improvement in overall survival. Armstrong et al (GOG 172) showed a 16-month improvement in overall survival with intravenous (IV) paclitaxel, IP cisplatin, and IP paclitaxel. IP chemotherapy has not been universally embraced by physicians and patients in part because of its toxicity, treatment schedule, and the fact that no IP regimen has been compared with the current standard of IV carboplatin and paclitaxel (N Engl J Med. 2006 Jan 5;354[1]:34-43).
While there have been improvements in 5-year survival over time, most women with advanced ovarian cancer will undergo additional chemotherapy in order to achieve subsequent remissions or maintain stability of disease. Other drugs that have Food and Drug Administration approval in the setting of recurrent ovarian cancer include topotecan, liposomal doxorubicin, gemcitabine, bevacizumab, altretamine, carboplatin, cisplatin, cyclophosphamide, and melphalan. Olaparib was recently approved as monotherapy in women with a germline BRCA-mutation who had received three or more prior lines of chemotherapy.
Minimally invasive surgery
Over the last 30 years, minimally invasive surgery (MIS) in gynecologic oncology, particularly for endometrial cancer, has gone from a niche procedure to the standard of care. The introduction of laparoscopy into gynecologic oncology started in the early 1990s. In a series of 59 women undergoing laparoscopy for endometrial cancer, Childers et al. demonstrated feasibility of the technique and low laparotomy conversion rates (Gynecol Oncol. 1993 Oct;51[1]:33-8.). The GOG trial, LAP2, supported the equivalent oncologic outcomes of MIS versus laparotomy for the treatment of endometrial cancer. While many surgeons and centers offered laparoscopic surgery, there were issues with the learning curve that limited its widespread use.
In 2005, the FDA approval of the robotic platform for gynecologic surgery resulted in at least a doubling of the proportion of endometrial cancer patients treated with MIS (Int J Med Robot. 2009 Dec;5[4]:392-7.). In 2012, the Society of Gynecologic Oncology published a consensus statement regarding robotic-assisted surgery in gynecologic oncology (Gynecol Oncol. 2012 Feb;124[2]:180-4.). This review highlights the advantages of the robotics platform with regards to expanding MIS to women with cervical and ovarian cancer; the improvements in outcomes in the obese woman with endometrial cancer; and that the learning curve for robotic surgery is shorter than for traditional laparoscopy. Issues requiring further research include cost analysis as the cost of the new technology decreases, and opportunities for improvement in patient and physician quality of life.