Winning Abstracts from the 2015 Medical Student Abstract Competition: Primary Vaginal Melanoma: An Incidental Finding on Routine Pelvic Examination

First Author: Ryan Loreno Lym, Case Western Reserve University School of Medicine, Class of 2016

Introduction: Primary vaginal melanoma is a rare and aggressive cancer. It accounts for less than 3% of vaginal cancers and less than 1% of malignant melanomas with an incidence of 0.26/10,000 women per year. Five-year survival rate ranges from 10-20% and there is no effective treatment. UV radiation is not the causative factor and its etiology is unknown. Workup requires pelvic examination of a vaginal lesion with biopsy and histopathological diagnosis.

Case: A 79-year-old woman with a history of endometrial carcinoma status post total hysterectomy in January 2013 was found to have a vaginal lesion in January 2014 on a routine pelvic exam. The exam was done according to current PAP smear guidelines for a patient whose hysterectomy was performed for endometrial carcinoma. The lesion was biopsied and determined to be primary vaginal melanoma. It was excised and initial staging showed no evidence of metastasis.

A follow up pelvic exam in March showed recurrence of three separate vaginal lesions that demonstrated recurrent melanoma. They were excised and PET-CT showed no distant metastasis. She subsequently completed whole pelvic radiation but in July a staging CT scan showed a lesion in the left lung that was confirmed to be metastatic melanoma. The patient was then put on Ipilimumab therapy.

In September she was admitted for complaints of dyspepsia, diarrhea, headache, and dyspnea concerning for progression of metastatic disease and Ipilimumab toxicity. EGD demonstrated erosive gastritis secondary to NSAID use. Bowels were positive for Clostridium Difficile and she was treated with metronidazole. CT scan showed diffuse metastases to the lung, liver, and pancreas. Brain metastasis was confirmed with volumetric MRI. Thoracentesis with subsequent PleurX placement was performed in an effort to relieve the dyspnea felt secondary to the diffuse lung metastases and malignant pleural effusion. Upon discharge it was established that she had failed Ipilimumab therapy and possible options for future management included gamma knife radiation with considerations for hospice and palliative care.

Discussion: Current guidelines recommend against pelvic exams in low risk women such as those older than 65 with adequate screening history or in those who have had a total hysterectomy for benign reasons. However, this case illustrates the importance of follow up pelvic exams in high-risk individuals. For this patient, despite her age and total hysterectomy, her history of endometrial carcinoma and primary vaginal melanoma prompted the need for post-treatment surveillance by pelvic exam. Her exams were important in detecting the presence of her primary vaginal melanoma and its recurrence.

Back to September 2015 Issue of IMpact