Challenge and Outcome for the Prostate Squamous Cell Carcinoma Which Developed 8 Years after Low-Dose-Rate Brachytherapy Approached by a Combined Multimodal Treatment with High-Dose-Rate Interstitial Brachytherapy, External Beam Radiation Therapy, and Chemotherapy.

Prostate squamous cell carcinoma (pSCC) rarely develops as a secondary cancer after treatment with low-dose-rate brachytherapy (LDR-BT). There is no established effective treatment for the disease condition. Herein, we present a 78-year-old man who developed pSCC 8 years after LDR-BT. He was subsequently selected to receive a combined multimodal treatment with high-dose-rate interstitial brachytherapy (HDR-ISBT), external beam radiation therapy, and chemotherapy for his pSCC. Eleven months later, he displayed no biochemical failure nor clinical radiographic recurrence. However, MRI detected a newly developed prostatic-rectal fistula (grade 4), and a colostomy was performed to relieve pain and inflammation. To our knowledge, this is the first report to perform a combined multimodal treatment with HDR-ISBT for pSCC suspected as a secondary cancer due to LDR-BT.

MRI features of the nested variant of urothelial carcinoma of the urinary bladder: report of four cases.

We report on four patients with the nested variant of urothelial carcinoma (NVUC) of the urinary bladder and focus on their magnetic resonance imaging (MRI) findings. MRI showed that all lesions had irregular wall thickening with little protrusion into the bladder lumen. All had extravesical invasion, and two had invaded other organs (uterus and seminal vesicle). On T2-weighted images, all tumors mainly showed relatively strong hypointensity similar to that of the muscularis propria, and in three cases there was also a thin hyperintense layer on the tumor surface, suggesting edematous mucosa. Diffusion-weighted images demonstrated different degrees of hyperintensity, which was faint in one case. Dynamic contrast-enhanced MRI was performed in two cases and both showed gradual contrast enhancement. It has been suggested that NVUC may produce unique MRI findings reflecting its pathological features. It would be useful for those who interpret bladder MRI to recognize this rare urothelial carcinoma variant.

MRI features of mucinous adenocarcinoma of the prostate: report of four cases.

CASE REPORTS: We report four patients with mucinous adenocarcinoma of the prostate, focusing on their magnetic resonance imaging (MRI) findings. The lesions appeared hyperintense on T2-weighted images (T2WI) in all four patients. In the two patients in whom the tumors were confined to the peripheral zone (PZ), the lesions were isointense to the surrounding normal PZ, making them difficult to identify. In all three patients who underwent diffusion-weighted imaging (b = 1000), the lesions appeared hyperintense but visually there was little or no decrease in the apparent diffusion coefficient (ADC), with ADC values of 1.02, 1.39, and 1.66 × 10-3 mm2/s, respectively. In the three patients who underwent a dynamic contrast-enhanced MR study, early enhancement was evident in two (partial in one), and gradually increasing enhancement in one. CONCLUSION: In the four cases in this instance, MRI findings of mucinous adenocarcinoma were very different from the appearance of non-mucinous adenocarcinoma. It is suggested that the conventional interpretation method of MRI for prostate cancer is not suitable for mucinous adenocarcinoma. Those who interpret prostate MRI should be aware of this rare and unique subtype of prostate cancer.