Nature and behavior of transitional tumors in the upper respiratory tract

A study has been made of 168 cases of transitional or inverted papillomas and 57 carcinomas showing a similar morphology, all having their origin in the upper respiratory tract. Two cases of papilloma underwent malignant change while under observation, and an additional 7 cases of paranasal carcinoma showed the simultaneous presence of papilloma and carcinoma in the primary biopsy. The significance of this association is discussed; it is concluded that the incidence of malignant change in the transitional papilloma may range from less than 2% to more than 5% depending upon the histologic interpretation. The transitional carcinoma of the upper respiratory tract has been redefined as a histologic entity justified on the basis of a better survival rate. In the larger, paranasal group, the 5-year survival rate of the transitional carcinomas was 38% as compared with 17% for squamous and 13% for ana-plastic carcinomas. No cause in the selection or management of the cases could be found to account for this difference which appears to be inherent in this particular type of carcinoma. The significance of the histologic pattern in relation to clinical staging of paranasal carcinoma is stressed.