Florica Stăniceanu 1, 2, Liana Tudorică 2, Sabina Zurac 1, 2, Gianina Micu 2, Eliza Grămadă 2, Alexandra Bastian 2, Cristiana Popp 2, Luciana Nichita 1, Al. Croitoru 3
1 University of Medicine and Pharmacy “Carol Davila”
2 Department of Pathology, Colentina University Hospital, Bucharest
3 Department of Surgery, Colentina University Hospital, Bucharest
Abstract
Adenosquamous carcinoma (AdSqCa) is a rare aggressive subtype of colorectal carcinoma with interesting issues concerning histogenesis, prognosis and appropriate management. We analyzed 9 cases of colonic AdSqCa diagnosed in our department in the last 4 years from a total of 330 cases of colonic epithelial malignancies. Histological features were reviewed and histochemical and immunohistochemical studies were performed in order to highlight specific characteristics of the tumors. The gross appearance of carcinomas varied within large limits but all of them showed the same rectosigmoidian location. Most of the cases had high grade of anaplasia as well as other histopathological signs of tumoral aggressiveness: ulceration, necrosis, perivascular and perineural invasion, tumoral emboli, extension to the entire colonic wall. Moreover, 3 patients presented advanced stage disease – either regional lymph node or liver metastasis. The cytonuclear pleomorphism was more pronounced and the proliferation indexes were higher in the squamous component than in the pure adenocarcinomatous counterpart. Its high biological aggressiveness should draw attention to the importance of correct diagnosis of these rare colonic neoplasms. We report our experience regarding an increased incidence and exclusive rectosigmoidian location of AdSqCa, singular features of this type of tumor identifi ed in medical literature. Moreover, the overall histopathological appearance and the immunohistochemical phenotype of the analyzed cases sustain the hypothesis of squamous metaplasia of the glandular adenomatous epithelium with subsequent malignant transformation as possible mechanism of AdSqCa histogenesis.