Urothelial-Type adenocarcinoma of the prostate mimicking metastatic colorectal adenocarcinoma

Mucin-producing urothelial-type adenocarcinoma of the prostate with sarcomatoid features and novel molecular phenotype

Introduction

Mucin-producing urothelial-type adenocarcinoma of the prostate is a rare tumor that may not elevate serum prostate-specific antigen, creating significant diagnostic and monitoring challenges. We evaluate our case in detail and review prior studies to demonstrate that the pathologic and molecular features of this tumor are distinct from conventional prostate adenocarcinoma.

Case presentation

Our patient had a remote history of radiation-treated conventional prostate adenocarcinoma and presented many years later with an abscess-like prostate mass leading to urinary obstruction and hematuria. Biopsy revealed mucin-producing urothelial-type adenocarcinoma of the prostate with concurrent sarcomatoid features. Molecular studies showed a unique phenotype involving alterations in the KRAS, PTEN, RAD21, and TP53 genes.

Conclusions

To our knowledge, this is the first report that describes sarcomatoid features and molecular mutations in mucin-producing urothelial-type adenocarcinoma of the prostate.

FDG PET/CT in a Case With Primary Poorly Differentiated Urothelial-Type Adenocarcinoma of the Prostate

ABSTRACT

Primary urothelial-type adenocarcinoma of the prostate is extremely rare. We describe FDG PET/CT findings in a case with primary poorly differentiated urothelial-type adenocarcinoma of the prostate with pelvic lymph node metastases. Both the prostate tumor and its metastatic lesions showed intense FDG uptake. The patient had normal serum prostate-specific antigen and elevated carcinoembryonic antigen levels, which may be helpful for the differential diagnosis.

A Rare Case of Co-Existing Mucin-Producing Urothelial-Type Adenocarcinoma of the Prostate and Acinar Adenocarcinoma

Mucin-producing urothelial-type adenocarcinoma of the prostate is an extremely rare neoplasm, and its coexistence with acinar adenocarcinoma is exceptional. A 70-year-old man presented with treatment resistant symptoms of urinary obstruction. The serum prostate specific antigen (PSA) level was normal. Cystoscopy revealed a kind of "cottony fluff" in the prostatic urethra. A computed tomography (CT) scan and magnetic resonance imaging (MRI) showed a polylobulated, hyperintense lesion with mucinous content. It was located in the right lobe of the prostate and measured 35 × 27 × 35 mm. The bladder cavity did not show lesions and the gastrointestinal endoscopy was normal. Thus, the patient underwent a radical cystoprostatectomy. The histological sections showed the characteristics of a mucin-producing adenocarcinoma with extensive areas of mucin pools formation. No areas of necrosis, glandular urethritis, or carcinoma in situ were identified. Neither lymphovascular and perineural invasion nor lymph node metastases were identified. The immunohistochemical study showed diffuse positivity for keratin (KRT) 7, KRT20, and membranous beta-catenin and focal positivity for KRT34betaE12 and caudal-related homeobox gene 2 (CDX2). In addition, we identified a 10-mm focus of prostatic acinar adenocarcinoma that was positive for racemase and NKX3.1. There is no treatment algorithm for this condition; however, surgery (radical prostatectomy) with or without adjuvant chemotherapeutic treatment represents a therapeutic alternative.

Mucin-producing urothelial-type adenocarcinoma of the prostate diagnosed after robot-assisted radical prostatectomy

INTRODUCTION

Mucin-producing adenocarcinoma of the prostate is a rare disease that includes prostate adenocarcinoma with mucus production, secondary adenocarcinoma from the bladder or colorectum, and adenocarcinoma from the urothelium of the prostatic urethra. We describe prostate-specific antigen-negative mucin-producing urothelial-type adenocarcinoma of the prostate.

CASE PRESENTATION

The patient had urinary retention and a serum prostate-specific antigen level of 0.74 ng/mL. Computed tomography and magnetic resonance imaging revealed a prostate tumor with a mucous component. We diagnosed adenocarcinoma by prostate biopsy and subsequently performed robot-assisted radical prostatectomy. Mucin-producing urothelial-type adenocarcinoma of the prostate was diagnosed by pathological examinations. Lung metastasis, developing within 3 months after surgery, was treated using chemotherapy.

CONCLUSION

Endocrine therapy is ineffective for mucin-producing urothelial-type adenocarcinoma of the prostate. Mucin-producing urothelial-type adenocarcinoma of the prostate diagnosis requires pathological and immunohistochemical analyses. It is important to surgically remove the primary lesion, and robot-assisted radical prostatectomy may provide an effective approach. Multimodal therapy is essential to treat for mucin-producing urothelial-type adenocarcinoma of the prostate.

Mucinous adenocarcinoma of the prostatic urethra following a remote history of primary brachytherapy for prostate cancer

Secondary malignancies are a known, albeit uncommon, complication of radiation for prostate cancer, either in the form of external beam radiotherapy or seed-implant brachytherapy. Of these secondary malignancies, mucinous adenocarcinoma of the prostatic urothelium is an extremely rare clinical entity that has only once been reported in the literature. We report the case of an 80-year-old gentleman who initially underwent low-dose brachytherapy for low-risk prostate cancer 18 years ago. He subsequently developed recurrent gross hematuria and obstructive voiding symptoms. He underwent cystoscopy and transurethral resection of a large tumor from within the prostate. Final pathology of the tumor revealed a mucinous adenocarcinoma. Further immunostaining revealed this is likely to have originated from the prostatic urothelium. Given his age, comorbidities, and no clear data demonstrating that aggressive extirpative surgery provides a clinical benefit, we elected to undergo surveillance. Clinicians should be aware of mucinous adenocarcinoma of the prostatic urethra as an extremely rare, radiation-induced malignancy. Once a diagnosis is made, extirpative surgery is an option for localized disease, although prognosis remains poor.

Aggressive course in a patient with mucin-producing urothelial-type adenocarcinoma of the prostate: A case report and review of the literature

Prostate cancer is one of the frequently seen types of cancers in men. The most frequent histological type of prostate cancer is the acinar adenocarcinoma. Mucin-producing urothelial-type adenocarcinoma of the prostate is a very rare subtype. The mucin-producing urothelial-type adenocarcinoma of the prostate has microscopic similarities with colon and bladder adenocarcinoma. It has a more aggressive clinical course and does not respond to androgen deprivation therapy. A 77-year-old male patient diagnosed with mucinous prostate cancer was presented in the current case report.

Co-existence of mucin-producing urothelial-type adenocarcinoma of the prostate and inverted papilloma of the bladder

Adenocarcinoma of prostate with mucinous differentiation arising in the male urethra is extremely rare, with only 21 cases reported in the previous literature. A diagnosis of mucin-producing urothelial carcinoma of the prostate is based on the pathology, immunohistochemistry, and clinical examination by excluding the secondary adenocarcinoma of the prostate. We present a case of unexpected mucinous urothelial carcinoma of prostate with co-existing inverted papilloma of bladder in a 57-year-old man. The patient underwent transurethral resection of the prostate (TURP) and transurethral resection of a bladder tumour (TUR-Bt), and the pathologic result showed mucinous prostate carcinoma and bladder inverted papilloma. Immunohistological stain was negative for prostate-specific antigen (PSA), prostate-specific acid phosphatase (PSAP), and P63, but positive for cytokeratin 7 (CK 7), CK 20, clone 34βE12 and P504S. A complete endoscopic examination was performed to exclude the secondary adenocarcinoma of prostate. This case illustrates the clinical and pathological features of a rare and unexpected mucin-producing urothelial carcinoma of prostate in a bladder neoplasm patient.

Demonstration of CDX2 is highly antibody dependant

OBJECTS

CDX2 is a widely used immunohistochemical marker for intestinal differentiation in neoplasms. In the Nordic Immunohistochemical Quality Control external quality assessment scheme, only 45% of the laboratories participating in the CDX2 challenge in 2009 produced sufficient staining. A major cause of insufficient staining results appeared to be less successful primary antibody (Ab) clones. To evaluate the Ab performance in a standardized way, a comparative study was carried out.

MATERIALS AND METHODS

Tissue microarrays containing 309 non-neoplastic tissues and tumor samples with expected high, low, and no CDX2 expression were used. Five Abs were selected for comparison: EPR2764Y concentrated (Conc), EPR2764Y in a ready-to-use format, and DAK-CDX2, AMT28, and CDX2-88, all Conc. The CDX2 stains were scored blindly using the H-score method. Tissue/tumor samples with a maximum H-score of 150 to 300 (on the basis of the staining giving the highest score) were classified as CDX2 high expressors, samples with a maximum H-score of 10 to 149 as low expressors, and samples with a maximum H-score <10 as negative.

RESULTS AND CONCLUSIONS

A total of 106 tumors were CDX2 positive with at least one of the Abs. For 56 high-expressor tumors, the mean H-scores with EPR2764Y Conc, EPR2764Y ready-to-use, DAK-CDX2, AMT28, and CDX2-88 were 262, 236, 234, 167, and 149, respectively, and the percentage of positive tumors 100, 100, 100, 98, and 93, respectively. For 50 low-expressor tumors, the mean H-scores with the same Abs were 59, 26, 28, 7, and 5, respectively, and the percentage of positive tumors 98, 58, 64, 18, and 14, respectively. With EPR2764Y Conc, CDX2 was demonstrated in 5/19 (26%) urothelial carcinomas, 7/64 (11%) lung adenocarcinomas, 5/30 (17%) large cell/sarcomatoid lung carcinomas, and 4/19 (21%) esophagus squamous cell carcinomas. In-house optimized protocols gave for all 4 Conc Abs better staining results than the vendors' recommended protocols. The sensitivity of CDX2 Abs and protocols must be taken into consideration when classifying neoplasms of unknown origin.

Mucin-producing urothelial-type adenocarcinoma of the prostate as a mimicker of colonic adenocarcinoma: a case report and review of the literature

A 59-year-old man presented with persistent urinary obstructive symptoms, gross hematuria, and mucusuria. Subsequently, a prostate-specific antigen (PSA)-negative mucin-producing urothelial type adenocarcinoma of prostate was found. The serum PSA level was within the normal limit. Colonoscopy, positron emission tomography, and other tumor surveys showed this to be the only prostate lesion. Microscopically, there was an adenocarcinoma with copious mucin production, with the formation of mucin pools. The neoplastic glands were variously arranged in cribriform, glandular, and villous adenoma-like patterns. This is a very rare tumor, of which there are only 20 cases reported in the literature in the English language. It is critical to distinguish it from mucinous acinar adenocarcinoma of the prostate and from metastatic adenocarcinoma of either the bladder or colon. This is mainly because mucin-producing urothelial type adenocarcinoma of the prostate has a different clinical behavior, and hence, the treatment plan is different from that for conventional prostatic adenocarcinoma. Specifically, it has a more aggressive clinical course and is unresponsive to hormone therapy.