Histogenesis of microscopic adenoma in nonpolypoid colons (those not included in the special disease group of familial polyposis coli) was investigated using complete serial sections with the following results: Adenoma arises from basal cells in the deep layer of the mucosa; and two types of basal cells found were 1) those which had already undergone changes to adenoma and 2) those which are in their transitional stage to adenomas. Early-phase growth of adenoma is brought about by branching. Individual hyperplastic (metaplastic) glands constituting so-called hyperplastic (metaplastic) polyps are considered to be only an expression of one variant in the growing process of adenomas and the glands showing these changes most characteristically have a serrated pattern. Based on these findings, the histogenesis of adenoma in nonpolypoid colons is shown schematically.

Adenoma↗

PubMedDate not supplied

Microscopic adenoma in nonpolyposis coli: incidence and relation to basal cells and lymphoid follicles.

Six microscopic adenomas found in four patients of nonpolyposis coli (namely, not included in the group of familial polyposis coli) which had been detectable microscopically but not macroscopically, were examined by preparing complete serial section. With respect to the histogenesis of large-intestinal adenomas in nonpolyposis coli, they are considered to originate from the basal cells. As the background for this, a great number of adenomatous changes in basal cells were seen, and the microscopic adenomas showed a tendency of multiplicity (in the present study a total of 36 microscopic adenomas were detected). The above-described adenomatous changes in basal cells and development of microscopic adenomas are considered to be closely related to lymphoid follicles on the muscularis mucosa, with 20 (55.6 per cent) of 36 microscopic adenomas originating in the basal cell upon the lymphoid follicles.

Adenoma↗

PubMedDate not supplied

Unusual CT and MR appearance of an epidermoid tumor of the cerebellopontine angle.

We present a case of an unusual epidermoid tumor of the cerebellopontine angle that appeared hyperdense on CT scans and hyperintense on T1- and T2-weighted MR images. We believe that these imaging characteristics were caused by a high protein concentration within the contents of the cyst.

Cerebellar Diseases↗