Appropriately Aggressive Management for a Rare Cancer

This Expert Perspective refers to a case presented here.

Vaginal carcinoma is rare, accounting for 1% to 2% of female genital cancers.[1] Squamous cell cancer accounts for 80% to 90% of vaginal cancers. Human papillomavirus (HPV) viral particles can be identified in approximately 60% of invasive squamous cancers of the vagina.[2]

The peak incidence of vaginal cancer is in the sixth and seventh decades of life, with only 10% of cancers occurring in women less than 40 years old.[3] The majority of vaginal cancers arise in the upper third of the vagina and most commonly arise in the posterior wall. Lymphatic drainage of upper-vaginal cancers follows the same pathways as cervical cancer, to the pelvic and para-aortic lymph nodes; lower-third lesions follow the drainage pathway of vulvar cancer, to the inguinal and pelvic lymph nodes.[1]

Because of the close proximity of the vagina to the urethra, bladder, and rectum, adequate surgical margins are difficult to obtain for any cancer of the vagina other than small cancers located in the upper, posterior region.Therefore, irradiation is usually the treatment of choice. As with cervical cancer, irradiation usually involves both whole-pelvis external-beam therapy and brachytherapy with a combination of vaginal cylinder and interstitial therapy. Based on the data from cervical cancer, most authorities recommend concurrent platinum-based chemotherapy administered with irradiation for vaginal cancer.

Unusual Patient

The patient presented in this case report is unusual in several respects. It is rare to see vaginal carcinoma in a 28-year-old woman, and it is very rare to see vaginal cancer in a pregnant patient. The anterior vaginal wall is not the most common location for a vaginal cancer. At 21 weeks’ gestation, the recommendation for termination of pregnancy and immediate treatment with chemotherapy and irradiation was very reasonable; however, it was certainly the patient’s choice, and given her decision to continue the pregnancy, management was appropriate.

Given the enlarged lymph nodes, many authorities would have recommended frozen section to confirm metastasis. If metastasis to the pelvic lymph nodes was confirmed, a complete para-aortic lymphadenectomy would have been a reasonable approach. If the para-aortic lymph nodes were negative, extended-field irradiation could have been avoided. Nevertheless, without a para-aortic dissection, the choice of extended-field irradiation was appropriate, considering the multiple metastases to pelvic nodes. Most would concur with the choice of concurrent weekly cisplatin(Drug information on cisplatin).

Additional Chemotherapy Issues

The issue of whether to give additional chemotherapy following completion of chemoirradiation is unresolved. Retrospective reviews of cervical data have indicated a possible benefit of additional systemic chemotherapy. The Radiation Therapy Oncology Group (RTOG) is currently considering a randomized study of an additional four cycles of systemic chemotherapy in high-risk cervical cancer (including metastasis to lymph nodes).

The long delay following therapy before recurrence was diagnosed can probably be attributed to the well-differentiated nature of the squamous cell cancer. Ideally, recurrent well-differentiated squamous cell cancer metastatic to the lung should be resected prior to additional therapy, but according to the case report, the recurrence was considered unresectable. Although there are no good data in the literature, one could consider concurrent chemotherapy along with the irradiation to the sites of metastasis.

In summary, this is an unusual case of well-differentiated squamous cell carcinoma occurring in a young pregnant woman. She was managed aggressively and appears to have had a good outcome.

—William J. Hoskins, MD