Primary prostatic signet-ring cell carcinoma

Prostate Adenocarcinoma with Signet-Ring Cells and Features of Mucin: A Clinical Case and Literature Review

Introduction: Signet-ring cells are typically associated with mucin-secreting epithelium; thus, they are most commonly found in the gastrointestinal tract, but not exclusively. Primary signet-ring cell carcinoma of the prostate is a rare and poorly differentiated, aggressive acinar adenocarcinoma variant with a grim prognosis. Clinical Case: In June of 2023, a 54-year-old Caucasian male presented with a complaint of lower urinary tract obstructive symptoms with occasional macrohematuria, non-specific body aches, and shortness of breath. A prostate specimen obtained in transurethral resection of the prostate was sent for histopathological examination. After a series of extraprostatic diagnostic workups, including fibrogastroduodenoscopy, colonoscopy computed tomography imaging, and immunohistochemical studies, the patient was diagnosed with primary prostatic signet-ring cell adenocarcinoma stage IV. Unfortunately, due to the advanced stage of the disease, PE, and third-degree thrombocytopenia, the patient was not a candidate for chemotherapy and died of cardiopulmonary insufficiency later that week. Discussion: Prostatic signet-ring cell carcinoma accounts for 0.02% of all prostate adenocarcinoma cases. Due to its nature and epidemiology, a diligent extraprostatic investigation has to be carried out. The disease often presents with unremarkable clinical symptoms and variable serum prostate-specific antigen results, which may contribute to its late diagnosis. Inconsistent immunohistochemical findings and an unpredictable response to hormonal treatment together pose both diagnostic and therapeutic challenges that negatively affect the prognosis. Conclusions: This study highlights the importance of a multidisciplinary approach and the need for diagnostic and therapeutic consensus within the research community in search of the primary site of the disease, which may positively influence the prognosis.

Mucin-producing tumors and tumor-like lesions involving the prostate: a comprehensive review

Mucin-producing tumors of the prostate include both primary and secondary tumors with mucinous differentiation or features involving the prostate gland. These tumors are relatively rare and have variable prognostic and therapeutic implications. Primary mucinous (colloid) adenocarcinoma of the prostate is defined as prostatic adenocarcinoma with mucinous differentiation involving 25% or more of the entire tumor. Another primary tumor of the prostate that may have mucinous features is primary mucin-producing urothelial-type adenocarcinoma of the prostate (mucinous prostatic urethral adenocarcinoma). Primary mucin-producing urothelial-type adenocarcinoma of the prostate is a distinct entity that typically arises from the prostatic urethra possibly from urethritis glandularis or glandular metaplasia with malignant transformation, and it is analogous to adenocarcinoma with mucinous differentiation arising from the urinary bladder. Signet ring cell tumors of the prostate, though rare, may also have mucinous features. Secondary tumors with mucinous differentiation that may involve the prostate include adenocarcinomas of the urinary bladder and colorectum. Pathologists should also be aware of mucin-producing tumor-like lesions involving the prostate, including mucinous metaplasia, and benign Cowper glands that may mimic malignancy. Herein we present an updated and comprehensive review of the clinicopathologic, immunohistochemical, molecular, and prognostic features of mucinous tumors and tumor-like lesions involving the prostate gland, with emphasis on mucinous prostatic adenocarcinoma and its mimickers, including potential diagnostic pitfalls.

Primary signet ring cell carcinoma of the prostate

Nine patients treated with primary signet ring cell carcinoma of the prostate were identified among 29,783 cases of prostate cancer evaluated at Mayo Clinic from January 15, 1970, until January 2, 2009. A PubMed search of the English-language literature published from January 1, 1980, to January 1, 2010, was then performed using the key words signet ring cell and prostate, identifying 42 cases. This study reviews those cases, along with the additional 9 reported herein, and evaluates clinical characteristics, histologic diagnoses, treatment modalities, and outcomes. Mean age at diagnosis was 68 years (range, 50-85 years), and mean prostate-specific antigen level was 95.3 ng/mL (range, 1.9-536.0 ng/mL; to convert to μg/L, multiply by 1). Most patients (66%) had non-stage IV carcinoma, the most common Gleason sum was 8 (33%), and mean survival was 29 months. The presence of a primary signet ring cell carcinoma of the prostate was best confirmed by negative findings on gastrointestinal work-up, a positive stain for prostate-specific acid phosphatase, and negative carcinoembryonic antigen test results.

Variants and Unusual Patterns of Prostate Cancer

Beyond the typical acinar morphology observed in most prostatic adenocarcinoma, a spectrum of morphologic variants and prostate cancer subtypes exists. These unusual entities may be further classified into (1) cancer morphologies arising by divergent differentiation of prostatic ductal, acinar, or basal cells and associated with unique clinical features or therapeutic approaches, and (2) histologies occurring in the context of usual prostatic adenocarcinoma that may result in diagnostic misinterpretation or difficulties in Gleason grade assignment, especially in limited samples. This article details several variants, with emphasis on diagnostic criteria, differential diagnoses, and clinical significance.

MUC2 expression in primary mucinous and nonmucinous adenocarcinoma of the prostate: an analysis of 50 cases on radical prostatectomy

The expression of mucin (MUC2) in prostate cancer has not been well studied previously and may be of prognostic and pathobiologic significance. It is, however, well known that MUC2 expression in mucinous pancreatic and breast cancer represents an indolent pathway since these tumors have a significantly better outcome than their conventional counterparts. Twenty-five cases each of Gleason pattern 3 and 4 mucinous adenocarcinoma of the prostate defined by greater than 25% mucinous component and nonmucinous adenocarcinoma of the prostate were obtained from the surgical pathology files of the Johns Hopkins Hospital and Emory University Hospital. Immunohistochemical stains were performed for MUC2 on all 50 cases. Mean patient age was 60 years (range 44-72 years). MUC2 was expressed in all 25 cases (100%) of mucinous adenocarcinoma of the prostate, irrespective of the Gleason pattern. The nonmucinous component of these cases was negative for MUC2. In contrast, MUC2 expression was significantly lower in nonmucinous adenocarcinoma of the prostate, detected in only 6/25 cases as a focal finding, while 19/25 (76%) of nonmucinous adenocarcinoma of the prostate were completely negative for MUC2 (P<0.01). In six cases that showed focal positivity, MUC2 was expressed in areas with Gleason pattern 3 cancer with extensive mucinous fibroplasia (one case) and prominent intraluminal mucin (five cases). Other areas of these tumors were negative for MUC2. Mucinous adenocarcinoma of the prostate shows diffuse expression of MUC2, a known tumor suppressor, which is not present in either normal prostate or the majority of conventional adenocarcinomas of this organ. This indicates that mucinous adenocarcinoma of the prostate is indeed of the 'colloid type' akin to those in other exocrine organs. It is highly conceivable that this de novo expression of MUC2 has a role, not only in the mucinous differentiation of these tumors and their colloid pattern, but also in their relatively indolent behavior that has been recently elucidated.

Cdx2, cytokeratin 20, thyroid transcription factor 1, and prostate-specific antigen expression in unusual subtypes of prostate cancer

There are some unusual histologic variants of prostate carcinoma, including mucinous, signet-ring cells, and ductal carcinomas that can metastasize in a problematic way and simulate lung, colorectal, or bladder primaries. Currently, antibodies that are organ-specific have been used in the routine surgical pathology practice. Our aim is to study the profile of expression of Cdx2, thyroid transcription factor 1 (TTF1), and cytokeratin 20 (CK20) in prostate cancer with unusual histologic finding. Twenty-nine prostate adenocarcinomas with unusual histologic findings were submitted to immunohistochemistry with prostate-specific antigen (PSA), CK20, Cdx2, and TTF1 antibodies. There were 7 mucinous, 5 ductal, 2 signet-ring cells, and 15 usual acinar adenocarcinomas with focal mucinous differentiation. To compare the results with usual acinar adenocarcinomas, we studied 10 primary and their respective lymph node metastases in a tissue microarray, 2 unusual metastatic adenocarcinomas, and 6 usual acinar high-grade carcinomas. For tumors with special histologic finding, Cdx2 was expressed by 9 (31.0%) mucinous, signet-cell, or with focal mucinous differentiation. Thyroid transcription factor 1 was moderately positive in mucinous differentiation areas of 2 (6.9%) adenocarcinomas. Cytokeratin 20 was expressed by 9 (31.0%) tumors, among them, 3 ductal adenocarcinomas. Prostate-specific antigen was positive in 28 (96.6%) cases and negative in 1 ductal adenocarcinoma. There was only 1 worrisome ductal adenocarcinoma that was strongly CK20 positive and PSA negative. Almost one third of mucinous prostate carcinomas express Cdx2. Cytokeratin 20 can be positive also in one third of prostate carcinomas, especially the ductal type. Pathologist should be alert when evaluating immunohistochemical profiles of unusual histologic findings of prostate cancer, mostly in distant sites.

A new case of signet ring cell carcinoma of the prostate

Primary signet ring cell carcinoma of the prostate is a very rare variant of prostate cancer. Herein, we report a new case of primary signet ring cell carcinoma of the prostate in an 85-year-old man with voiding disorder and hematuria. Based on this case, we present the anatomopathologic, clinical, and therapeutic aspects of this rare entity.

Primary mucin-producing urothelial-type adenocarcinoma of prostate: report of 15 cases

Prostatic urothelial-type adenocarcinoma arises through a process of glandular metaplasia of the prostatic urethral urothelium and subsequent in situ adenocarcinoma sometimes associated with villous adenoma. These prostatic adenocarcinomas are analogous to nonurachal adenocarcinomas arising in the bladder from cystitis glandularis. Only 2 cases of urothelial-type adenocarcinoma from an institution other than our own have been previously described. The distinction between adenocarcinoma from another organ secondarily involving the prostate, usual adenocarcinoma of the prostate, and prostatic urothelial-type adenocarcinoma can present a significant diagnostic challenge and has significant therapeutic implications. Fifteen cases of prostatic urothelial-type adenocarcinoma were retrieved from the consult files of one of the authors. Mean patient age at diagnosis was 72 years (range 58 to 93 y). All men had negative colonoscopies, clinically excluding a colonic primary. Bladder primaries were ruled out clinically or pathologically in radical resection specimens. Follow-up was available on all men with a mean of 50.3 months (range 2 to 161 mo). All men presented with urinary obstruction symptoms with 3 (20%) also having mucusuria and 2 (13.3%) also having hematuria. Four men (26.7%) developed metastatic disease and 8 (53.3%) died of disease. In 8/15 (53%) cases, glandular metaplasia of the prostatic urethra and contiguous transition to adenocarcinoma were identified. Multiple histologic patterns were observed including dissection of the stroma by mucin pools 15/15 (100%), villous features 7/15 (47%), necrosis 2/15 (13.3%), signet ring cells 3/15 (20%), perineural invasion 1/15 (6.7%), focal squamous differentiation 1/15 (6.7%), and a granulomatous inflammatory response 1/15 (6.7%). Immunohistochemical stains were negative for prostate specific antigen, prostate specific acid phosphatase, CDX2, and beta-catenin in all cases. Stains were positive for high molecular weight cytokeratin in 12/12 cases (100%), and CK7 and CK20 in 10/12 cases (83.3%). Prostatic urothelial-type adenocarcinoma is a rare aggressive cancer arising in the prostate. The differential diagnosis includes conventional prostatic mucinous adenocarcinoma and secondary infiltration from a colonic or bladder adenocarcinoma. Immunohistochemistry for prostate specific antigen, prostate specific acid phosphatase, and high molecular weight cytokeratin along with morphology can help rule out conventional prostate carcinoma. beta-catenin, CDX2, and clinical studies are needed to rule out colonic adenocarcinoma. As prostatic urothelial-type adenocarcinoma is entirely analogous to bladder adenocarcinoma in both, its morphology and immunophenotype, only clinical studies or in some cases pathologic examination of the cystoprostatectomy specimen can exclude infiltration from a primary bladder adenocarcinoma.

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.

Primary signet ring cell carcinoma of female urethra

A 69-year-old woman presented with difficulty in urination and bloody fluid discharge from the urethra. Based upon a diagnosis of primary urethral carcinoma, she underwent total cysto-urethrectomy and hysterectomy with pelvic lymph node dissection and urinary diversion of ileal conduit. Microscopically, the tumor was composed of mucinous adenocarcinoma and signet ring cell carcinoma. There was no recurrence 17 months after the surgery.

[Mucinous carcinoma of the prostate: critical review of Elbadawi's criteria]

OBJECTIVES

We present our experience on prostatic mucinous adenocarcinoma and at once we practice an actualization and a critical review of Elbadawi's criteria.

METHODS

After reviewing 206 prostatic carcinomas diagnosed in our hospital, we describe one case that fulfill criteria for being considered a prostatic mucinous adenocarcinoma. We also carry out a wide literature review trying to define anew the including criteria of this tumour by the light of modern knowledge and technology.

CONCLUSIONS

We think that for accepting a tumour as a prostatic mucinous adenocarcinoma, this have to fulfill the following criteria: 1. "More than 25% of a significative tumoral sample is mucinous pattern and present, single or clustered, tumour cells floating in immunohistochemically probed, acidic and neutral, mucin lakes". 2. "Tumour is Gleason 3-4 cribiform pattern with direct transition to colloid areas and usually coexist with classic adenocarcinoma but papillary growth patterns should be excluded. Tumour may contain a moderate proportion of signet-ring cells". 3. "Immunohistochemical staining for PSA have to be strongly positive in both, cribiform and mucinous, areas". 4. "Those PSA nonreactive, or only focally positive, mucinous adenocarcinomas, could be labeled as prostatic only when local or distant mucinous carcinomas are ruled out".

The prostatic gland: malignancies other than adenocarcinomas

Many rare variants of prostatic carcinoma have been described and characterized in recent years. Accurate diagnosis of these variants is necessary in order to determine appropriate therapy. Unusual tumors arising in the prostate raise questions of histogenesis, and may carry a better or worse prognosis than typical adenocarcinoma. Virtually the entire spectrum of cellular differentiation has been observed within prostatic epithelium, and rare neoplasms exhibit these unusual forms of differentiation as the chief component of the tumor. Except in sarcoma (marked prostatic enlargement), imaging plays a limited role in the diagnoses of these entities. Biopsy and histologic diagnoses are essential and the role of imaging is restricted to the evaluation of locoregional and distant spread of the disease.

Prostatic signet-ring cell carcinoma: case report and literature review

Signet-ring cell carcinoma (SRCC) of the prostate is a very rare neoplasm and there have been only 38 cases reported to date. Here the 39th case of prostatic SRCC containing a small amount of neutral mucin, prostatic specific antigen (PSA) and prostatic specific acid phosphatase (PSAP) in the signet-ring cells is reported. It was also found that some intracytoplasmic lumina were derived from the shallow or deep invagination of luminal membranes of cancer cells that formed the neoplastic glands. Using immunohistochemistry, a combination of monoclonal antibodies against cytokeratins 7 and 20 as well as PSA and PSAP may be useful in differentiating prostatic primary SRCC from metastatic SRCC originating in the gastrointestinal tract.

Oliguria, an unusual presentation of primary signet ring-cell adenocarcinoma of the urinary bladder: a case report and review of the literature

Adenocarcinomas represent approximately 2% of primary bladder epithelial malignancies. Of these, the signet ring-cell variant is the rarest form. We report such a case, with the unusual presentation of oliguria, including radiologic and histopathologic findings. The current literature is reviewed.

Unusual histologic types of high-grade prostatic intraepithelial neoplasia

High-grade prostatic intraepithelial neoplasia (HGPIN) is the most likely precursor proliferation of peripheral zone, moderately to poorly differentiated prostatic adenocarcinomas. The usual cell type of the epithelial lining of HGPIN is a glandular epithelial cell with characteristic nuclear abnormalities. Here we report nine cases of unusual types of HGPIN, including three cases of signet-ring cell HGPIN, one case of small cell neuroendocrine HGPIN, and five cases of HGPIN with distinctive mucinous features. The three examples of signet-ring cell PIN were all associated with an invasive primary signet-ring cell carcinoma of the prostate. The HGPIN assumed a classical tufted and micropapillary architectural growth pattern, with the constituent cells exhibiting a morphologic appearance identical to that of the invasive signet-ring cells. The intraepithelial and invasive signet-ring cells were mucin negative and were immunoreactive for prostate-specific antigen (PSA). A fourth case displayed a mixed intraepithelial glandular-small cell neoplastic proliferation, where intraepithelial small cells were histologically identical to surrounding invasive small cell carcinoma cells. The small cell HGPIN and invasive small cell carcinoma cells were positive for the neuroendocrine markers chromogranin, synaptophysin, and neuron-specific enolase. In five cases, mucinous distension of HGPIN glands, producing a flat pattern of the epithelial lining layer, comprised the third unusual pattern of HGPIN. These blue mucinous secretions were readily detected by hematoxylin and eosin staining and were composed of both neutral (periodic acid-Schiff-positive) and acidic (alcian blue-positive) mucins. Herein we document the existence of an intraepithelial proliferation of neoplastic cell types-small cell neuroendocrine and signet-ring cell-that are usually considered as stromal-invasive cells in the prostate. The presence of these rare prostatic cell types in both HGPIN and invasive carcinoma provides further support for a close relationship between HGPIN and invasive carcinoma of the prostate. All three unusual types of HGPIN-signet-ring cell, small cell neuroendocrine, and mucinous-are important to diagnostically recognize because of the strength of association of HGPIN with invasive carcinoma.

Signet-ring carcinoma of the prostate

A case of prostatic signet-ring adenocarcinoma is described in a man with a history of open prostatectomy for prostate carcinoma (18 years previously). Immunostaining confirmed the prostatic origin of the signet-ring tumor which stained for prostatic acid phosphatase (PSAP) and prostate specific antigen (PSA). Cytokeratin immunostaining showed the vacuoles to be true lamina with clear and distinct outlines, the feature confirmed by ultrastructural examination. This aggressive tumor is an uncommon but distinct variant of primary prostatic carcinoma which should be distinguished from artefactual vacuolation of tumor, inflammatory and stromal cells, and metastatic disease.

Mucinous adenocarcinoma of urinary bladder type arising from the prostatic urethra. Distinction from mucinous adenocarcinoma of the prostate

We describe two cases of mucinous adenocarcinomas involving and confined to the prostate and originating from the prostatic urethra. These cases were identical to adenocarcinomas arising within the urinary bladder and differed from mucinous adenocarcinoma of the prostate. In both cases, an in situ adenocarcinoma component was identified in the overlying prostatic urethra. In one case the in situ adenocarcinoma arose in a villous adenoma of the urethra. Both cases contained lakes of mucin lined by tall columnar epithelium with varying degrees of cytologic atypia, and one case had mucin-positive signet cells. In contrast, mucinous adenocarcinomas of the prostate demonstrate tubules and cribriform glands floating within mucin; mucin-positive signet cells are rare. Both tumors were negative immunohistochemically for prostate-specific antigen and prostate-specific acid phosphatase and positive for carcinoembryonic antigen. One case was treated by radical prostatectomy, and the patient was without evidence of disease with short follow-up. Following simple prostatectomy, the other patient did not undergo definitive therapy for several years, at which point the tumor had progressed locally to an advanced stage. In terms of therapy, the distinction between mucinous adenocarcinoma or urinary bladder-type arising in the prostate depicted within the current study and mucinous adenocarcinoma of the prostate is significant.