Prognostic indicators of occult metastases in oral cancer.

Abstract

We evaluated the importance of several tumor factors related to predicting the presence of occult metastases in the oral cavity. Retrospective case study. The study comprises 29 patients treated at the Department of Otorhinolaryngology (University of Trieste, Cattinara Hospital, Trieste, Italy) between January 1990 and December 2000, who had T1-T2 carcinoma of the oral cavity that had or had not extended to the oropharynx and were clinically evaluated as N0 neck. The patients all underwent surgery with removal of tumor and neck dissection. Four tumor-related parameters were examined with the aim of evaluating their predictivity of metastasis: tumor class, degree of keratinization, degree of differentiation according to Brooler's histopathological grading, and invasive cell grading (ICG). With the exception of tumor class, these parameters were evaluated both in the biopsy and in the surgical specimen and the findings were then compared. We evaluated existing correlations between each individual parameter and the histopathological presence of micrometastases (pN+) and extracapsular spread revealed when specimens from the neck were examined. There was a highly significant correlation between ICG equal to or greater than 13 (range, 5-20) and the presence of occult metastases (P =.0017). On the basis of our findings, the ICG parameter correctly identified 9 of 10 (pN+) patients and could have reduced overtreatment from 65.5% to 17.2% in histopathologically negative necks (pN0). It would appear that with a delay in programming a neck dissection so as to consider ICG in combination with thickness, as in seven recent patients, identification of locoregional occult metastases (pN+) might be more precise.