However, the majority of histologies are non-keratinizing squamous cell carcinomas (SCCs) and its cloacogenic
, transitional, and basaloid variants.
([PSI]) The study included 44 cases of squamous cell carcinoma, 3 cases of adenocarcinoma, and 8 cases of cloacogenic
Acrochordon (skin tag) Kaposi's sarcoma Basal cell carcinoma Malignant melanoma Condylomata acuminata Perianal abscess/fistula Crohn's disease Pilonidal cyst/abscess Cutaneous tuberculosis Squamous cell carcinoma/ Bowen's disease Epidermoid cyst Thrombosed external hemorrhoid Hidradenitis suppurativa Perianal basaloid (cloacogenic
) squamous cell carcinoma
In the 4th edition of WHO classification of tumors of female reproductive organs, primary villoglandular mucinous adenocarcinoma is defined as a primary invasive glandular epithelial tumor of intestinal type and the synonyms are cloacogenic
carcinoma or cloacogenic
The onset of symptoms is often abrupt, with the duration of symptoms for cloacogenic
carcinoma being generally shorter in comparison to those for squamous cell anal neoplasms .
Epidermoid (Squamous Cell) carcinoma is the most common histological variant and represents about 75%-80% of anal cancer cases; somewhat less common is Basaloid Transitional cell (Cloacogenic
Squamous cell (epidermoid) carcinomas, which include cloacogenic
(basaloid transitional cell) tumors, account for most anal cancers, with adenocarcinoma accounting for the rest.
Three of those (60%) had also been deferred to a consensus group at the time of original diagnosis: (1) dysplasia in a patient with inflammatory bowel disease, (2) an inflammatory cloacogenic
polyp with prolapse changes, and (3) a difficult uterine stromal proliferation.
Therefore, cancers are predominantly SCCs, adenocarcinomas, or basaloid and cloacogenic
carcinoma arise from the mucosa of transitional or cloacogenic
zone separating the rectal and anal mucous membranes.
In the literature, this epithelium has been variously designated as transitional, intermediate, or cloacogenic
. Scattered foci of colorectal crypts or small areas of mature squamous epithelium may also be seen in the ATZ.