[A comparative study on proliferative activity in different histological patterns of adenoid cystic carcinoma--from a viewpoint of nuclear DNA contents].

Adenoid cystic carcinoma generally consists of the following histologic features: tubular, cribriform, trabecular, and solid. To investigate how these histological patterns affect the prognosis of this carcinoma, we determined the proliferative activity of each of the histologic patterns by cytofluorometry. Twenty-six cases of adenoid cystic carcinoma, obtained by surgical resection, were studied. According to predominant histological pattern, they were divided into three groups: seven cases were of cribriform pattern, nine cases of trabecular pattern, and ten cases of solid pattern. The region with each dominant pattern was obtained from biopsy specimen, and the nuclear DNA contents of the tumor cells of the regions were assayed. In four of twenty-six cases, that of the tumor cells of the region with other patterns in the same specimens were also assayed. The results were the following: 1) The mean incidence of over 4.5C-polyploid cells of the region with predominant pattern of each tumor significantly increased in the following order: cribriform pattern and solid pattern. 2) The incidence of over 4.5C-polyploid cells, in comparison of a predominant pattern with other histologic patterns in the same tumor, were calculated. It was higher in solid pattern than in trabecular pattern, and was higher in trabecular pattern than cribriform pattern. 3) Only two of ten cases, had aneuploidy in the region with predominant solid pattern and the other cases had diploid stem line. Judging from the above results, it was concluded that proliferative activity of each pattern increased in the following order: cribriform pattern, trabecular pattern, solid pattern.(ABSTRACT TRUNCATED AT 250 WORDS)