Secondary Malignancies of the Bladder: Avoiding the Diagnostic Pitfall

Metastatic Sites in Rare Genitourinary Malignancies and Primary Cancer Sites in Genitourinary Organ Metastases: A Secondary Analysis Using the Japanese Pathological Autopsy Registry Database

Background

The epidemiology of metastases from rare genitourinary cancer and metastases to genitourinary organs from other primary neoplasms remains poorly understood.

Objective

To investigate the epidemiology of rare genitourinary metastases from rare genitourinary organ-type cancer and to genitourinary organs using data from a large national autopsy registry in Japan.

Design setting and participants

A secondary analysis of the data reported in the Annual of the Pathological Autopsy Cases in Japan and the Japanese Mortality Database from 1993 to 2020 was performed.

Outcome measurements and statistical analysis

Via a retrospective epidemiologic analysis, we evaluated the frequency (probability of occurrence [number per person]) and proportion (percentage) of metastases from upper urinary tract, adrenal, testicular, urethral, and penile cancers. Moreover, the sites of primary tumors metastasizing to genitourinary organs were examined.

Results and limitations

In Japan, the mortality rate of upper urinary tract cancer is increasing rapidly. In the integrated database with 365 099 autopsies and 835 959 metastatic organs, the major metastatic sites (range of frequency ratios) of rare genitourinary organ-type cancers were the lungs (0.38-0.47), liver (0.21-0.56), bone (0.16-0.33), adrenal gland (0.10-0.20), peritoneum (0.0-0.16), and kidneys (0.07-0.22). The major primary sites (range of proportions) of genitourinary organ metastases were the respiratory tract (5.6-34.0%), stomach (4.7-27.0%), hematologic site (0.9-24.9%), lymphoid (2.4-22.2%), bladder (0.8-20.0%), prostate (0.7-14.1%), rectal (2.0-11.7%), and pancreas (2.6-11.0%). The cancers with a high likelihood of genitourinary metastasis were respiratory and stomach cancers. However, the study lacked individual-level information, and there might be a concomitant selection bias in this autopsy study.

Conclusions

This large-scale autopsy database analysis identified the epidemiology of metastasis from rare genitourinary organ-type cancer and the origins of metastasis to genitourinary organs.

Patient summary

This study provides valuable metastatic epidemiologic data and clinical information that are fundamental to the mechanisms of genitourinary metastasis.

Clinical and pathological characteristics of metastatic tumors to the urinary bladder

Metastatic carcinoma to the urinary bladder is a rare and under-recognized condition in surgical pathology. In this study, we identified 8 cases of true bladder metastasis at our institution in the past 20 years, excluding secondary tumors via direct extension or serosal implantation. The most common tumor type is malignant melanoma (3/8), followed by clear cell renal cell carcinoma (2/8), adenocarcinoma of the gastrointestinal tract (2/8), and breast invasive lobular carcinoma (1/8). There are 6 cases of endoscopically exophytic metastasis and 2 cases of diffuse metastasis, commensurate with 6 patients with hematuria and 2 patients with urinary obstruction as respective clinical symptoms. Exophytic bladder metastasis usually presents with similar clinical features as urothelial carcinoma, while diffuse metastasis often masquerades as a urinary tract infection. In the latter circumstance, a markedly thickened bladder wall discerned via imaging study is the best indication for the bladder biopsy to circumvent the misdiagnosis. Histologically, the metastatic tumors can also mimic conventional urothelial carcinoma or its histological variants, and thus pose a potential diagnostic challenge to pathologists. The lack of an in situ component in primary bladder cancer may hint at bladder metastasis. Accurate diagnosis of bladder metastasis requires heightened alertness to this rare condition in addition to a multidisciplinary approach.

Case Report: Analysis of four cases of metastatic bladder masses after radical prostatectomy

Objective

The aim of this study is to investigate the clinical characteristics and diagnostic and therapeutic methods of bladder metastasis after radical prostatectomy and to improve its diagnosis and treatment.

Methods

The clinical data of four patients with bladder metastasis after radical prostatectomy were retrospectively analyzed from January 2011 to December 2021. Three cases suffered from intermittent gross hematuria, and only one case was found to have an elevated prostate-specific antigen (PSA) value. Transurethral resection of bladder tumor was performed in four cases, in which one case also underwent resection of urethral mass. Three cases received endocrine therapy, one of which added intravesical instillation and radiation therapy. Another case received chemotherapy based on comprehensive treatment.

Results

According to the pathological and immunohistochemical results, three cases were acinar adenocarcinoma of the prostate with Gleason score of 9, and all cases were PSA positive and negative for cytokeratin 7 (CK7) and GATA binding protein 3 (GATA-3). One case was small cell neuroendocrine carcinoma of the prostate and was positive for chromogranin A (CGA), synaptophysin (SYN), and cluster of differentiation 56 (CD56). During the follow-up period of 4 to 13 months, one case was lost to follow-up and three cases were alive.

Conclusion

Bladder metastasis after radical prostatectomy is rare, and pathology combined with immunohistochemistry is the gold standard for its diagnosis. Pathological type determines its treatment. Systemic treatment is essential, and local treatment is the most palliative means. Early diagnosis and treatment is significant for better prognosis.

Secondary neoplasms of the urinary bladder-clinical management and oncological outcomes

Background

Secondary neoplasms of the bladder account for 4.5% of all bladder neoplasms however there is limited literature reporting management and survival. This is the largest single centre series presented in current literature with long term oncological follow up.

Methods

This is a single institutional, retrospective cohort study of patients with a histological diagnosis of a secondary bladder neoplasm from January 2007 to December 2017 (n=40). Prognostic variables examined included age at diagnosis, histology, disease free survival and treatment. Kaplan-Meier analysis was used to calculate survival. We used multiple regression analysis to identify the most significant treatments for each population group in terms of their survival.

Results

Twenty-one patients were male (53%) with a median age of 68 and 19 were female (47%) with a median age of 64. The most common secondary neoplasms and their median survival were prostate [12 patients (30%), 446 days], colorectal [9 patients (23%), 403 days], ovarian [5 patients (13%), 369 days], cervical [4 patients (10%), 148 days], breast [3 patients (8%), 241 days], lymphoma [3 patients (8%), 145 days], gastric [2 patients (5%), 66 days], and renal [2 patients (5%), 854 days]. Those receiving treatment following a secondary diagnosis demonstrated statistical significance in survival for colorectal (surgery P=0.013), prostate (radiotherapy P=0.0012 and hormonal therapy P=0.004) and ovarian cancer (chemotherapy P=0.00002).

Conclusions

Prognosis and treatment depends upon the primary neoplasm. There is some survival benefit in well selected patients receiving treatment following a diagnosis of a bladder secondary.

Secondary tumors of the bladder: A survival outcome study

The urinary bladder may be involved by a variety of secondary tumors that originate from other organs. Bladder secondary tumors are rare and may be mistaken as bladder primary tumors because of their overlapping morphologic features. To avoid the diagnostic pitfalls, we analyzed the clinicopathologic features of bladder secondary tumors in a large cohort of patients. Our patient cohort consisted of 45 females and 38 males with a mean age of 58.7 ± 15.4 years (range 10-87 years). The tumors involved the bladder via direct extension from adjacent organs (n = 42) and distant metastasis (n = 41). In females, the majority of secondary tumors originated from the gynecologic tract (n = 25), and other common origins included the colon/rectum (n = 5) and breast (n = 4). In males, the most common origin was the prostate (n = 18), followed by the colon/rectum (n = 4) and kidney (n = 3). 75.9% of the secondary tumors were adenocarcinoma (n = 63), and other common tumor types included sarcoma (n = 6), squamous cell carcinoma (n = 5), melanoma (n = 4), and neuroendocrine carcinoma (n = 3). 67.5% of patients (n = 56) died of the disease with a median overall survival of 23 months from the time of secondary involvement of the bladder. Patients with secondary tumors via direct extension had a median survival time of 20 months, which was not significantly different from that for patients with secondary involvement via distant metastasis (24 months) (p = 0.83). Median survival in cases with prostate primary was 20 months as compared to 23 months for all other tumor types (p = 0.68). The majority of secondary tumors are composed of adenocarcinoma, which highlights the importance of differentiating primary from secondary involvement in bladder adenocarcinoma. Regardless of the origin, bladder secondary tumors are associated with a poor prognosis.