Mucinous adenocarcinoma of the prostate

Almost all infiltrating colloid carcinomas of the pancreas and periampullary region arise from in situ papillary neoplasms: a study of 39 cases

Colloid carcinomas of organs such as the breast, colon, and prostate have been well characterized. However, up until now there have been only a few studies of colloid carcinomas of the pancreas and periampullary region, and the number of colloid carcinomas in these studies has been limited. A search of our files revealed 39 resections for pancreatic and periampullary carcinomas with colloid differentiation. All neoplasms were extensively sampled. "Carcinomas with colloid differentiation" were defined as tumors associated with abundant extracellular mucin containing free-floating mucinous epithelial cells. Cases with >50% colloid differentiation were classified as "colloid carcinomas," whereas those with less were termed "carcinomas with focal colloid features." Cases with no colloid differentiation at all were designated "carcinomas without colloid differentiation." Of the 39 carcinomas, 31 were colloid carcinomas, and eight were carcinomas with focal colloid features. Twenty-seven were centered in the pancreas, seven were in the duodenum, and five were in the ampulla of Vater. Remarkably, 38 of the 39 carcinomas (97%) arose in association with an intraductal papillary mucinous neoplasm or a tubular/tubulovillous adenoma. Of the patients with colloid carcinomas, the 2-and 5-year actuarial survival rates were 69% and 29%, respectively. There was no significant difference in survival rates between patients with colloid carcinomas and patients with adenocarcinomas without colloid differentiation, whether or not the latter arose in association with intraductal papillary mucinous neoplasms or tubular/tubulovillous adenomas. In a multivariate model colloid differentiation was not an independent predictor of patient survival, while other factors such as tumor location, perineural invasion, vascular invasion, and margin status after resection independently influenced patient survival. Most colloid carcinomas of the pancreas and periampullary region arise in association with a well-defined in situ papillary neoplasm. The diagnosis of a pancreatic or periampullary colloid carcinoma should encourage the pathologist to search for an associated low-grade in situ component. In addition, colloid carcinomas of the pancreas and periampullary region do not necessarily have a better prognosis than carcinomas without colloid differentiation. Instead, other factors such as tumor location, perineural invasion, vascular invasion, and margin status after resection are far more important.

The monoclonal antibody 7E12H12 can differentiate primary adenocarcinoma of the bladder and prostate

OBJECTIVE

To determine if the monoclonal antibody 7E12H12, which reacts with a 40 kDa protein in normal human enterocytes and has been shown to be a marker for intestinal metaplasia and adenocarcinoma arising in the bladder, could assist in distinguishing prostatic, urachal and vesical adenocarcinoma, using a sensitive immunohistochemical assay.

MATERIALS AND METHODS

Fifteen primary prostatic adenocarcinomas and five adenocarcinomas of the urinary bladder were selected for a retrospective evaluation. The monoclonal antibody 7E12H12 (IgM isotype) was used in an immunoperoxidase assay to survey formalin-fixed, paraffin-embedded archival tissue specimens.

RESULTS

All vesical adenocarcinomas reacted positively with the antibody, regardless of grade; none of the 15 prostatic specimens reacted positively in either the benign or malignant glandular epithelium.

CONCLUSION

The monoclonal antibody 7E12H12 can differentiate primary adenocarcinoma of the bladder from secondary adenocarcinoma arising in the prostate and may be a useful tool in diagnostic pathology.

Adenosquamous carcinoma of the prostate

We describe a patient with adenosquamous carcinoma of the prostate. His history suggests a common histogenesis of the glandular and squamous elements of the tumor. A 60-year-old white man had adenocarcinoma of the prostate diagnosed by biopsy and then underwent radical prostatectomy, which showed adenosquamous carcinoma. Immunoperoxidase in the glandular component was positive for prostate-specific antigen (PSA), prostatic acid phosphatase (PAP), and low molecular weight keratin CAM 5.2 but was negative for high molecular weight keratin AE-3. The squamous component was negative for PSA, PAP, and CAM 5.2 but positive for AE-3. Previously reported patients with adenosquamous carcinoma of the prostate share a history of radiation or hormonal therapy followed much later by prostatectomy, suggesting that adenosquamous carcinoma consists of residual primary adenocarcinoma and metaplastic squamous epithelium caused by radiation or hormonal treatment. However, the present case lacks this history, suggesting that the two types of epithelia may have developed concurrently.

Signet-ring cell carcinoma of the prostate mimicking primary gastric carcinoma

A post mortem examination of a 70 year old man, who died three years after a poorly differentiated adenocarcinoma of prostate had been diagnosed, showed widespread signet-ring cell carcinoma, with an associated linitis plastica. The signet-ring cells stained positively with prostatic specific antigen and with prostatic specific acid phosphatase, but failed to react with mucopolysaccharide staining. The electron microscopic appearance of the signet-ring cell tumour was due to the presence of large cytoplasmic vacuoles. This case emphasises the possibility that cases of metastatic signet-ring cell carcinoma may be prostatic in origin. This can be confirmed by specific immunohistochemical studies.

Mucinous adenocarcinoma of the prostate: histochemical and immunohistochemical studies

Twelve patients with primary mucinous adenocarcinoma of the prostate were included in a clinicopathologic study; criteria included a total tumor volume more than 25% mucinous and single or clustered tumor cells floating in mucin lakes. Patient ages were 57 to 81 years; tumor stages were C (three), D (five), and unknown (four). Bone was the most frequent metastatic site (usually osteoblastic), followed by lymph nodes and lungs. Serum levels of prostatic acid phosphatase and prostate-specific antigen were frequently elevated (five of 10 and three of three measured, respectively). All mucinous adenocarcinomas also contained other histologic patterns: microglandular (four), cribriform (three), comedo (two), solid (two), and hypernephroid (one). Mucinous components composed less than 50% of three tumors, 50% and 75% of six, and more than 75% of three. No tumor contained signet-ring cells. Immunoperoxidase staining was positive for prostatic acid phosphatase and prostate-specific antigen and negative for carcinoembryonic antigen. Treatment was radiation, estrogen, orchiectomy, or a combination. In two of four patients, serum prostatic acid phosphatase levels normalized after therapy. Seven patients died of disease (mean follow-up, 56 months), and five patients are alive with disease (mean, 32.2 months). The proportion of mucinous component did not affect prognosis.

Mucins in prostatic carcinoma

Mucin production by prostatic carcinomas is not unusual and the identification of acidic mucin with an appropriate stain may be a useful adjunct in routine diagnostic surgical pathology. In our series of 53 cases of prostatic carcinoma, 20 (38%) showed significant acidic mucin production. This may allow differentiation from benign, hyperplastic tissues which produce neutral mucins only. A case of colloid carcinoma of prostate is described which satisfies Elbadawi's criteria for this uncommon variant. Some suggestions are made which, if rigorously applied, will permit the recognition of genuine cases of colloid carcinoma and of the prognostic significance of mucin-rich tumours.

Signet ring cell carcinoma of prostate. Immunohistochemical and ultrastructural study of a case

Signet ring cell adenocarcinoma (SRCA) is an extremely rare tumor of the prostate. We document with histochemistry, immunohistochemistry, and electron microscopy an incidental "signet ring" cell adenocarcinoma of the prostate in a fifty-seven-year-old white male with chronic lymphocytic leukemia who died of an intracerebral hemorrhage. The signet ring cells stained weakly for neutral mucin and were strongly positive for both prostate-specific antigen and prostate acid phosphatase. In addition, electron microscopy demonstrated intracellular lumina with microvilli and cytoplasmic vacuoles of mucin. This case conclusively supports the existence of SRCA of the prostate.

Primary signet-ring cell carcinoma of the prostate

The occurrence of signet-ring cells within a mucinous prostatic carcinoma is an extremely rare finding. This cancer is characterized by both intracellular retention and extracellular secretion of mucinous material. We report a case of primary signet-ring cell carcinoma of the prostate that was confirmed by autopsy. The results of gross, microscopic, and immunohistochemical examinations are described.

Primary endodermal sinus tumor of the prostate: report of a case

A 29-year-old man was admitted to the Department of Urology of the University of Padova with a diagnosis of prostatic adenocarcinoma. Cystourethrography showed a prostatic urethral obstruction, and CT scan demonstrated a low pelvic solid mass involving the prostate and the seminal vescicle. A radical prostatectomy was performed, and the prostate was found to be widely infiltrated by a neoplasia formed by tubules, papillary structures, and solid cords of cuboidal or flat elements, each having indistinct borders and scant cytoplasm, in a myxoid or fibrous stroma. "Schiller-Duval-like," PAS-diastase-resistant and alfa-fetoprotein hyaline bodies were present. An endodermal sinus (yolk-sac) tumor was diagnosed. There was infiltration of the periurethral prostatic ducts, prostatic urethra, and seminal vesicles and single lymph node metastasis. Testicular echotomography was negative. In spite of aggressive surgery and chemotherapy, the patient died 10 months after diagnosis. This is the third case in the literature after those presented by Benson and Michel.