Metastatic Prostate Cancer to the Urethra Masquerading as Urothelial Carcinoma

Multiple metastases of androgen indifferent prostate cancer in the urinary tract: two case reports and a literature review

BACKGROUND

Prostate cancer (PC) is mainly known to metastasize to bone, lung and liver, but isolated metastases of prostate cancer, including ductal carcinoma, in the urinary tract are very rare. We describe two patients with nodular masses in the urinary tract (the anterior urethra or the urinary bladder) that were found on cystoscopy during treatment of castration-resistant prostate cancer.

CASE PRESENTATION

In both cases, the pathological diagnosis from transurethral tumor resection showed that they were androgen indifferent prostate cancer (AIPC), including aggressive variant prostate cancer (AVPC) in Case 1 and treatment-induced neuroendocrine differentiation prostate cancer (NEPC) in Case 2. In Case 1, Loss of genetic heterozygosity (LOH) of BRCA2 and gene amplification of KRAS was identified from the urethra polyps. In Case 2, homozygous deletion was observed in PTEN, and LOH without mutation was observed in RB1.

CONCLUSION

These are the first reports of two cases of urinary tract metastasis of AIPC.

Isolated recurrence of prostate cancer to the anterior urethra 5 years after radiation therapy

INTRODUCTION

Primary or metastatic urethral tumors are extremely rare. However, treatment strategies differ between primary and metastatic tumors. Therefore, establishing an accurate diagnosis is critically needed for initiating timely and appropriate therapy.

CASE PRESENTATION

We describe the case of a 79-year-old man with prostate cancer treated with radiotherapy and androgen deprivation therapy. He presented with macroscopic hematuria as a symptom of anterior urethral tumor at follow-up. Endoscopic tumor resection was performed. Hematoxylin and eosin staining showed adenocarcinoma component. Immunohistochemical staining revealed presence of metastatic prostate cancer to the urethra.

CONCLUSION

Regarding urethral tumors diagnosis, urologists should consider the possibility of metastasis from prostate cancer and perform immunohistochemical examination for establishing accurate diagnosis. Furthermore, if androgen deprivation therapy fails to suppress symptoms, radiotherapy or urethrectomy might be considered.

Unusual presentation of castrate-resistant prostate cancer with urethral and inguinal nodal metastasis

Metastatic involvement of the urethra is a rare finding in patients with carcinoma prostate. The signs and symptoms overlap with those of a primary urethral malignancy. The diagnosis is made following a biopsy of the suspected lesions. We describe the case of a 66-year-old patient with carcinoma prostate who presented with penile pain, 18 months after the treatment with androgen deprivation therapy. Ga-68 prostate-specific membrane antigen positron emission tomography/computed tomography helped in the identification of the urethral and inguinal nodal metastasis, which was confirmed histologically. We also discuss the management of this unusual clinical scenario.

Isolated urethral metastasis from appendiceal mucinous adenocarcinoma

We are presenting a compelling case of a 61-year-old female with a history of appendiceal mucinous adenocarcinoma (AMA) with a new complaint of irritative lower urinary tract symptoms. Magnetic resonance imaging (MRI) showed a semi-circumferential, T2 hyperintense, rim enhancing, and lacking restricted diffusion lesion involving the urethra and infiltrating the right perineal and internal obturator muscles. The suspected differential diagnosis was urethral malignancy, based on her cancer history and MRI findings. After interdisciplinary consensus, the patient underwent excision of the lesion, and pathology was consistent with metastasis from the primary tumor. The urethra is a rare site of primary malignancy and metastatic disease. In particular, a non-contiguous metastatic disease involving the urethra is exceedingly rare. To the best of our knowledge, this is the first report of an AMA metastasizing to the urethra.

A Case of Metastatic Prostate Cancer to the Urethra That Resolved After Androgen Deprivation Therapy

An 83 year-old male with Gleason score 4+3 prostatic adenocarcinoma status post brachytherapy developed obstructive voiding symptoms 9 years after brachytherapy. Prostate-specific antigen was 0.67. Cystoscopy noted multiple papillary urethral tumors concerning for primary urethral carcinoma. Immunophenotype of biopsies supported diagnosis of Gleason score 4+4 prostatic adenocarcinoma. Androgen deprivation therapy was started. Cystoscopy performed 4 years later, for microhematuria workup, noted complete resolution of the urethral tumors. We present a patient with little serum Prostate-specific antigen change with urethral prostatic adenocarcinoma metastasis that resolved after androgen deprivation therapy.

Suppression of T24 human bladder cancer cells by ROS from locally delivered hematoporphyrin-containing polyurethane films

Systemic injection of a photosensitizer is a general method in photodynamic therapy, but it has complications due to the unintended systemic distribution and remnants of photosensitizers. This study focused on the possibility of suppressing luminal proliferative cells by excessive reactive oxygen species from locally delivered photosensitizer with biocompatible polyurethane, instead of the systemic injection method. We used human bladder cancer cells, hematoporphyrin as the photosensitizer, and polyurethane film as the photosensitizer-delivering container. The light source was a self-made LED (510 nm, 5 mW cm-2) system. The cancer cells were cultured on different doses of hematoporphyrin-containing polyurethane film and irradiated with LED for 15 minutes and 30 minutes each. After irradiating with LED and incubating for 24 hours, cell viability analysis, cell cycle analysis, apoptosis assay, intracellular and extracellular ROS generation study and western blot were performed. The cancer cell suppression effects of different concentrations of the locally delivered hematoporphyrin with PDT were compared. Apoptosis dominant cancer cell suppressions were shown to be hematoporphyrin dose-dependent. However, after irradiation, intracellular ROS amounts were similar in all the groups having different doses of hematoporphyrin, but these values were definitely higher than those in the control group. Excessive extracellular ROS from the intended, locally delivered photosensitizer for photodynamic treatment application had an inhibitory effect on luminal proliferative cancer cells. This method can be another possibility for PDT application on contactable or attachable lesions.