Anal cancer

Perianal mucinous adenocarcinoma arising from chronic anorectal fistulae: a review from single institution

BACKGROUND

Mucinous adenocarcinoma arising from a chronic anorectal fistula is rare, with few reports in the literature. Such lesions can be misdiagnosed for the more common benign perianal abscess or fistula.

METHODS

From our retrospective chart review, we identified three patients with chronic perianal fistula-in-ano who were subsequently found to have developed perianal mucinous adenocarcinoma on biopsy. We recorded the symptomatology, subsequent management and further follow-up of each patient.

RESULTS

Two of three patients who received irradiation and chemotherapy were still alive during 28 and 24 months of follow-up, respectively without any evidence of distant metastasis. One patient with inguinal lymph node metastases died due to distant metastasis 6 months after diagnosis.

CONCLUSIONS

Fistula-associated perianal mucinous adenocarcinoma is an uncommon malignant transformation of chronic fistula-in-ano. MRI can provide important diagnostic information on patient with this suspicious inflammatory condition. Although radical resection of the tumour with abdominoperineal resection remains the surgical treatment of choice. Combined chemoradiotherapy may be appropriate for these patients with promising results.

Anal human papillomavirus testing with Digene's hybrid capture 2 using two different sampling methods

PURPOSE

The incidence of human papillomavirus detection in the anal canal is rising. Efficient anal screening by cytology is hampered because of poor specificity. Human papillomavirus (HPV) testing is proposed in addition to Papanicolaou (Pap) testing for the detection of cervical neoplasia. The purpose of this study was to determine the usefulness of a human papillomavirus-DNA detection test to detect human papillomavirus-associated disease and to compare two different methods of sample collection.

METHODS

In 555 patients, anal samples were obtained by using a cervical brush and a Dacron swab to test for high-risk and low-risk human papillomavirus-DNA. Patients positive for human papillomavirus-DNA underwent anoscopy. Biopsies were taken from visible lesions.

RESULTS

Low-risk human papillomavirus-DNA was found in 325 of 555 patients (58.6 percent) and high-risk human papillomavirus-DNA in 285 of 555 patients (51.4 percent). Positive results confined to one single test method were higher for Dacron swab sampling (2.3 vs. 4.3 percent for low-risk human papillomavirus, P < 0.0001; 3.1 vs. 4.9 percent for high-risk human papillomavirus, P < 0.001). A positive correlation of relative light units was found for both sampling methods in the total cohort (P < 0.0001) as well as for patients who tested human papillomavirus-positive by both sampling techniques (P < 0.0001). Sampling with Dacron swabs yielded higher relative light units values compared with sampling with cervical brush for low-risk human papillomavirus-DNA and high-risk human papillomavirus-DNA.

CONCLUSIONS

Anal screening for human papillomavirus-DNA by hybrid capture 2 is a useful method for detection of human papillomavirus-associated disease. Sample collection using Dacron swabs identifies more human papillomavirus-positive patients, and yields higher relative light unit values than using the cervical brush. Further studies are needed to determine the exact value of hybrid capture 2 in the screening for (pre)cancerous lesions of the anal canal.