The subspecialty of gynecologic oncology was formalized less than 50 years ago with the creation of the Society of Gynecologic Oncology and subspecialty training and board certification. The formation of the Gynecologic Oncology Group (GOG) – and the many clinical trials spearheaded by that group – has further advanced evidence-based treatments, resulting in improved survival outcomes, quality of life, and preventive strategies.
While it is not possible to provide a comprehensive and exhaustive review of all of the advances, we hope to highlight many of the notable advances in this article.Cervical cancer
Cervical cancer is the fourth most common cancer in women worldwide with 528,000 new cases in 2012. The majority of cervical cancer cases are caused by infection with human papillomavirus (HPV). While the standard therapies for cervical cancer have been long established (radical hysterectomy for stage I and radiation therapy for locally advanced disease), one of the most significant advances in the past 50 years was the addition of radiation-sensitizing chemotherapy (cisplatin) administered concurrently with radiation therapy.
In randomized trials in both early and advanced cervical cancer, the risk of death was reduced by 30%-50%. These studies changed the paradigm for the treatment of cervical cancer (N Engl J Med. 1999 Apr 15;340[15]:1137-43; N Engl J Med. 1999 Apr 15;340[15]:1144-53; J Clin Oncol. 2000 Apr;18[8]:1606-13).
Future studies evaluating biologic adjuncts or additional chemotherapy are currently underway or awaiting data maturation.
The American Society of Clinical Oncology (ASCO) highlighted the “Top 5 advances in 50 years of Modern Oncology” in 2014, and second on the list was the approval of the HPV vaccine to prevent cervical cancer. Vaccines have been developed that can protect against types 2, 4 or 9 of HPV. In a 2014 study, depending on vaccination coverage, the relative number of cervical cancer cases avoided was 34% in Africa, 27% for America, 26% for Asia, 21% for Europe, and worldwide was estimated at 27% (Vaccine. 2014 Feb 3;32[6]:733-9).
While the benefit from HPV vaccination has been proven, in the United States, only about a third of eligible girls and women have been vaccinated. Efforts should focus on expanding vaccination penetration to eligible girls, boys, women, and men.
Endometrial cancer
Endometrial cancer is the most common gynecologic malignancy in the United States with an estimated 54,870 cases and 10,170 deaths annually. Notable advances in the management of women with endometrial cancer have arisen because of a better understanding that there are two types of endometrial cancer – type I and type II.
The type I endometrial cancers tend to be associated with lower stage of disease at the time of diagnosis and fewer recurrences, while type II endometrial cancer is associated with worse outcomes.
Tailoring the surgical approaches and adjuvant therapy for women with endometrial cancer has led to improved outcomes. The GOG conducted a large prospective randomized trial of laparotomy versus laparoscopic surgical staging for women with clinical early-stage endometrial cancer (LAP2). Laparoscopy was associated with improved perioperative outcomes and was found to be noninferior to laparotomy with regards to survival outcomes (J Clin Oncol. 2012 Mar 1;30[7]:695-700). Therefore, minimally invasive surgery has become widely accepted for the surgical staging of women with endometrial cancer.
Appropriate surgical staging allows for tailoring of postoperative adjuvant therapy. The current evidence suggests that vaginal brachytherapy should be the adjuvant treatment of choice over whole pelvic radiation in women with early-stage endometrial cancer (Lancet. 2010 Mar 6;375[9717]:816-23). Studies are underway to evaluate the role of both adjuvant radiation and chemotherapy in women with early-stage type II endometrial cancer who are felt to be at high risk for recurrent disease, as well as how to improve on the therapeutic options for women with advanced or recurrent disease.
Ovarian cancer
Epithelial ovarian cancer is the most deadly gynecologic malignancy in the United States with 21,290 cases and 14,180 deaths in 2015. The concept of ovarian tumor debulking was first described by Dr. Joe Meigs in 1934, but did not gain traction until the mid-1970s when Dr. C. Thomas Griffiths published his work (Natl Cancer Inst Monogr. 1975 Oct;42:101-4).
While there are no randomized trials proving that surgical cytoreduction improves overall survival, most retrospective studies support this concept. In 2009, Chi et al. showed improved median survival in women with ovarian cancer based on the increased percentage of women who underwent optimal cytoreduction (Gynecol Oncol. 2009 Jul;114[1]:26-31). This has led to modifications of surgical techniques and surgical goals with an effort to maximally cytoreduce all of the visible disease.