vacuoles in acinar adenocarcinoma of the prostate

Adenocarcinomas of the prostate may contain clear vacuoles and these should be distinguished from true signet-ring carcinomas which contain mucin.

Whereas vacuoles in adenocarcinoma of the prostate are not uncommon, true mucin-positive signet-ring cell carcinomas of prostate are exceedingly rare with only a handful of bona fide cases reported in the literature.

Vacuoles may distort the architecture and it is controversial as to what grade should be assigned.

Gleason’s only mention of vacuoles described them as signet cells under pattern 5 tumor.

The panel concluded that although typically vacuoles are seen within Gleason pattern 4 cancer, it may be seen within Gleason pattern 5 and even Gleason pattern 3 tumors.

The consensus was that tumors should be graded, as if the vacuoles were not present, by only evaluating the underlying architectural pattern.