Mucosubstance-rich myxoid stromal nodule of the prostate

A stromal tumor nodule of the prostate, located in the suburethral region, was incidentally retrieved by transurethral resection in a 72-year-old man with prostatism. Tumor fragments were grossly gelatinous and friable. The nodule consisted of a myxoid population of bland spindle cells lying in a matrix rich in acidic mucosubstance, mostly resistant to hyaluronidase. Capillary and venular vascular grouping and interspersed mast cells were conspicuous features. Phenotypical characterization revealed a population of fibroblasticlike cells. The associated prostatic tissue showed nodular glandular hyperplasia only. Whether this prostatic nodule represents a neoplasm or an unusual variant of hyperplastic stromal nodule is unclear.