BASALOID-SQUAMOUS CARCINOMA - A CLINICAL COMPARISON OF 2 HISTOLOGIC TYPES WITH POORLY DIFFERENTIATED SQUAMOUS-CELL CARCINOMA

Basaloid squamous carcinoma (BSC) of the head and neck has been shown to have a poor prognosis when compared with conventional squamous cell carcinoma (SCC), Pathologically, specimens determined to be BSC can h ave nearly pure basaloid features (group 1) or a mixture of basaloid a nd squamous features (group 2), The clinical behavior in these 2 subgr oups has not been compared previously. BSC is also commonly confused h istologically with poorly differentiated SCC (PDSCC), A retrospective comparison of disease stage at presentation, rate of distant metastasi s, rate of local recurrence in those offered surgical resection, and r ate of survival is made to compare outcomes of the 2 BSC groups and th e PDSCC group. The presence of particular histologic features may be a ssociated with poorer outcomes. Patients with BSC have advanced diseas e at presentation. Survival in the BSC group was less than half that i n the PDSCC groups. Statistical analysis shows the 2 groups to be well matched with regard to stage and site of disease. Presence of neck no dal disease on presentation predicts poor survival. In this study dist ant metastases occurred in 52% of patients with BSC and in 13% of pati ents in the PDSCC group. The local recurrence rate is comparable for B SC and conventional SCC, with even early tumors in the BSC group recur ring distantly rather than locally or regionally. Considering the high distant metastatic rate of BSC and poorer overall survival rate, a mo re extensive metastatic survey is indicated in these patients before s urgery is recommended. We recommend that patients with a diagnosis of BSC not be included with conventional SCC groups in prospective random ized cancer protocols.