What Are Gynecological Malignancies?
Gynecological malignancies are among the common malignancies in females after breast cancer. As per the latest statistics, cervical cancer is the second most common cancer in women in India, with nearly 1 lakh new registrations happened in 2018. 1,46,420 new cases were registered last year with either of the common gynecological malignancies (cervix, ovary, or uterus). 5-year survival rates for localized cervical, ovarian, and uterine cancers are 91.8 %, 92.4 %, and 95 %; whereas those in case of node-positive cases are 56.3 %, 75.2 %, and 69 % respectively. In the case of distant metastasis, these rates drastically drop to 16.9 %, 29.2 %, and 16.8 % respectively. These rates reflect the importance of timely detection and treatment. 80 %, 36 %, and 89 % cases are either localized or node-positive, respectively.
These numbers demonstrate the obvious fact, that cervical and uterine cancers most commonly present at a stage where good cure rates are still possible, unfortunately, more often ovarian cancers present in the advanced stage. We have many guidelines which help us plan treatment for these malignancies. The most commonly employed guideline is NCCN (National Cancer Comprehensive Network), which gives accurate management decisions based upon the latest evidence.
As per the latest NCCN guidelines for cervical cancer, surgery is recommended only for early stages (FIGO stage IA and IB), for all other loco-regional cases, radiation with weekly concurrent platinum-based chemotherapy is the treatment of choice. Concurrent chemotherapy amplifies the effect of radiation and also has survival benefit.
Radiation is also recommended after surgery if the histopathological report is suggestive of adverse features such as positive margins, lymphovascular invasion, parametrium invasion, positive nodes, deep stromal invasion and size more than 4 cm (Sedlis criteria). There are multiple studies which have demonstrated the increased chances of recurrence if radiation is not given in the presence of such adverse features.
How Is Radiation Therapy Helpful in the Treatment of Such Malignancies?
Radiation therapy is delivered in two formats external beam radiotherapy (EBRT) and brachytherapy (BT).
- EBRT is delivered over five weeks, usually 25 fractions or sittings, in which the patient lies down in supine position, similar to the positioning for a CT scan procedure. The radiation is delivered from the machine head called gantry, which can rotate 360 degrees and is capable of providing from different angles, while the patient lies still. Duration of EBRT during each sitting is usually not more than 10 minutes. With advances in technology, now EBRT can be delivered by minimizing the doses to urinary bladder and rectum, thus reducing the probability of radiation induced genitourinary and gastrointestinal side effects without compromising tumor control probability.
- Brachytherapy is an inpatient procedure, where metallic tubes are placed inside the uterus, in which radiation source is placed with remote technology, thereby ensuring the safety of the personnel involved. This source then delivers radiation to the tumor, the effect of which is up to 2-3 cm from the tube (source), thus ensuring minimum side effects. Usually, 2 to 3 such sittings are required, depending upon response to EBRT, probability of side effects, patient’s age, etc.
What Are the Surgical Treatment Options?
Surgery is an essential treatment in the management of loco-regional uterine cancers. Usually, the recommended surgery is a hysterectomy, bilateral salpingo-oophorectomy, bilateral pelvic node dissection, or para-aortic nodal dissection, which depends upon baseline disease. It is very important that appropriate imaging (CT scan, MRI, or PET-CT) is done before proceeding towards surgery. Based upon adverse histopathological features, further radiation therapy and chemotherapy are recommended.
Adverse features include high grade, deep myometrial invasion, and lymphovascular invasion. In advanced stages, combination chemotherapy is recommended, usually 3 weekly for 6 cycles. The general principle being, to minimize the risk of local recurrence, radiation therapy is needed, whereas to mitigate systemic relapses, chemotherapy is required.
Ovarian malignancies are known for their advanced stage presentation. Usually, they are managed by surgery and combined chemotherapy. Role of radiation therapy is limited and still investigational.
Thus, for management of these malignancies is multimodality requiring the expertise of doctors of various knowledge inclusive of surgical, medical and radiation oncologists; also a good pathologist, radiologist, nuclear medicine expert is needed to provide the crucial information about the disease, thus helping in taking treatment decisions.