RESUMO
PURPOSE: In this paper, we report the results of studying the degree of reactive small round cell infiltration in the stroma as a prognostic indicator of maxillary sinus carcinoma treated with the Kitasato method and the effect of preoperative irradiation at 8 Gy on infiltration in the stroma. SUBJECTS: Out of 74 patients who had been treated with this method in the 27 years from 1976 to 2002, the following patients were enrolled in this study: (1) 17 patients from whom tissue specimens could be obtained with biopsies or probe antrotomies before preoperative irradiation, and (2) 40 patients from whom tissue specimens could be obtained after preoperative irradiation including those who survived five years and who died of a specific cause. METHOD: We classified the pattern of distribution of small round cell infiltration in the stroma into three degrees. (1) Stromal infiltration was compared before and after the operation to recognize the prognosis for each patient based on the pattern of distribution of small round cell infiltration in the stroma. (2) The correlation between the degree of stromal infiltration and prognosis was studied statistically. RESULTS: (1) Both the patients with increased stromal infiltration and those postoperatively preserving a preoperative score of 2+ with irradiation at 8 Gy had a good prognosis. (2) The five-year survival rate for patients was significantly higher in those with a score of 2+ for their tissue specimens. CONCLUSION: The Kitasato treatment method is effective and improves the QOL of patients with maxillary sinus carcinoma. The prognosis was good in the patients with increased or preserved stromal infiltration. The low-dose irradiation and chemotherapy used in combination seemed to be biological response modifiers.