Skip lesions in perianal mucinous adenocarcinoma

Abstract

Perianal mucinous adenocarcinoma (PMA) is a rare gastrointestinal malignancy that occurs in patients with a long-standing history of recurrent perirectal abscesses or a chronic fistula. We present a unique case of PMA, which began as a rectal abscess and progressed to PMA with a skip lesion present all the way up in the mid-rectal region. This is the first case in which PMA presented with skip lesions as opposed to a continuous lesion, and presented without fistulas and recurrent abscesses history but just a 4-day history of perianal burning, itching, and tingling. CT imaging, MRIs, and PET scans were done for the diagnosis of PMA. A discussion of the National Comprehensive Cancer Network (NCCN) guidelines on using radiation therapy followed by an abdominoperineal resection with inguinal node dissection for the management and treatment of PMA is reported. Sharing the presentation of PMA with multimodality specialty groups and tumor boards helps develop various diagnostic and therapeutic approaches for PMA, as well as enhances our understanding of this rare malignant entity.