Background and Clinical Significance: Calcinosis cutis is a rare condition that can develop through several mechanisms. These include dystrophic, calciphylaxis (classical, metastatic, and iatrogenic), and idiopathic mechanisms. Idiopathic calcinosis cutis is rare and always a diagnosis of exclusion. A particularly rare site for the development of idiopathic calcinosis cutis is the penis. Case Presentation: A previously healthy 18-year-old male presented to our institution with a three-month history of a painless, firm swelling on the outer layer of the prepucium in the area of the commissure. Histopathology of the excised specimen showed a varying caliber of calcium deposits within the dermis, ranging from small psammoma-like bodies to larger calcium deposits measuring up to 2.5 mm. The deposits were freely dispersed within the dermal collagen and did not exhibit vascular affinity, nor surrounding foci of inflammation. The epidermis was not involved, with only mild reactive hyperkeratosis. The results of detailed physical, imaging, and laboratory tests were normal, and hence the diagnosis of idiopathic calcinosis cutis of the penis was established. Conclusions: Penile calcinosis cutis is a rare condition that falls within the broader group of genital calcinosis cutis. The condition is typically present in young males and has an excellent prognosis after excision.

Background and Clinical Significance: Prostatic malignancies are amongst the leading malignancies in incidence. They represent a mixed group of conditions, predominantly characterized by adenocarcinomas, which are themselves predominantly acinar. Case Presentation: Herein, we present a morphological case report of a 73-year-old male who underwent transrectal ultrasound-guided needle biopsy due to elevated PSA levels (18.61 ng/mL). Histopathology of the biopsy specimen was represented by pleomorphic cells with predominantly clear cytoplasm, with relatively eccentric, pyknotically appearing nuclei with hyperchromatic chromatin and no visible nucleoli. After imaging excluded concomitant renal malignancy and confirmatory immunohistochemistry was carried out, the patient was diagnosed with renal-type clear cell carcinoma of the prostate. Conclusions: While unrecognized by the WHO due to its rarity, renal-type clear cell acinar adenocarcinoma of the prostate is a unique type of prostatic malignancy, which, due to its morphological appearance, necessitated careful differential diagnosis.

Background and Clinical Significance: Urothelial carcinoma is one of the most commonly diagnosed malignant diseases. However, it has a much more favorable prognosis than other significantly less common malignancies. This statement, however, is true only for conventional urothelial carcinomas, not for those with divergent differentiation or a special type of urothelial carcinoma. Case Presentation: Herein, we present a case report of an 80-year-old female patient with multiple predominantly cardiovascular comorbidities and vascular dementia, who presented to our institution with genital bleeding. Clinical and diagnostic tests were difficult due to patient noncooperation; however, abdominal computer tomography and cystoscopy showed an advanced tumor originating from the ventral bladder wall. Histology of the tumor showed an invasive urothelial malignancy with foci of clear-cell (glycogen-rich) variant and dispersed, pleomorphic cells, which were immunohistochemically positive for beta-human chorionic gonadotropin. Hence, the diagnosis of high-grade urothelial carcinoma with clear-cell (glycogen-rich) morphology and divergent trophoblastic differentiation was established. Patient outcome was poor. Conclusions: While conventionally having a somewhat favorable prognosis, special subtypes and divergent differentiation in urothelial carcinomas, which warrant a high-grade diagnosis are not only rare but also highly aggressive conditions. Further challenges arise in their differential diagnosis with other advanced malignancies, which can develop in adjacent organs in both genders