Recurrent membranous nephropathy with a possible alteration in the etiology: a case report

Background Phospholipase A2 receptor 1 (PLA2R1) and thrombospondin type-1 domain-containing 7A (THSD7A) are the two major pathogenic antigens for membranous nephropathy (MN). It has been reported that THSD7A-associated MN has a higher prevalence of comorbid malignancy than PLA2R1-associated MN. Here we present a case of MN whose etiology might change from idiopathic to malignancy-associated MN during the patient’s clinical course. Case presentation A 68-year-old man with nephrotic syndrome was diagnosed with MN by renal biopsy. Immunohistochemistry showed that the kidney specimen was negative for THSD7A. The first course of corticosteroid therapy achieved partial remission; however, nephrotic syndrome recurred 1 year later. Two years later, his abdominal echography revealed a urinary bladder tumor, but he did not wish to undergo additional diagnostic examinations. Because his proteinuria increased consecutively, corticosteroid therapy was resumed, but it failed to achieve remission. Another kidney biopsy was performed and revealed MN with positive staining for THSD7A. PLA2R1 staining levels were negative for both first and second biopsies. Because his bladder tumor had gradually enlarged, he agreed to undergo bladder tumor resection. Pathological examination indicated that the tumor was THDS7A-positive bladder cancer. Subsequently, his proteinuria decreased and remained in remission. Conclusions This case suggests that the etiology of MN might be altered during the therapeutic course. Intensive screening for malignancy may be preferable in patients with unexpected recurrence of proteinuria and/or change in therapy response.

Ectopic Prostate Tissue Presenting as Urinary Bladder Tumor: The Imitation Game!

Ectopic prostate tissue is a rare phenomenon. Histologically and immunohistochemically it is indistinguishable from normal prostatic tissue but it is difficult to recognize and may be confused with malignancy when presenting as ectopic lesion in the urinary system. Therefore, awareness of this entity is essential for both urologists and pathologists to prevent misdiagnosis.

Yolk Sac tumor differentiation in urothelial carcinoma of the urinary bladder: A case report and differential diagnosis

Background: Yolk sac tumor (YST) is a germ cell neoplasm that arises predominantly in the gonads, but can also derive from somatic neoplasms in extragonadal locations. These latter cases have been documented in several organs, although reports from the urinary tract are limited. To our knowledge, this is the first report of a bladder urothelial carcinoma with a predominant component of YST differentiation.Case presentation: We present a unique case of a 76-year-old man with a recurrent urinary bladder tumor, initially interpreted as a high grade urothelial carcinoma with glandular differentiation. In the recurrent tumor, diverse histological patterns were identified, including glandular, hepatoid and sarcomatoid. This tumor showed positivity for AFP, GLP3 and SALL4, and negativity for CK7 and EMA. Fluorescent in situ hybridization study showed a polysomic pattern of chromosome 12. All these findings led to the final diagnosis of a YST derived from urothelial carcinoma. Conclusions: YST differentiation should be considered in the differential diagnosis of a high grade urothelial carcinoma, particularly when glandular and other unusual patterns are observed.

Somatically derived Yolk Sac tumor of the urinary bladder: A case report and differential diagnosis

Background: Yolk sac tumor is a germ cell neoplasm that arises predominantly in the gonads, but can also derive from somatic neoplasms in extragonadal locations. These cases have been denominated recently as “somatically derived Yolk sac tumors”, and have been documented in several locations, although reports from the urinary tract are scarce. To our knowledge, this is the first report of a Yolk sac tumor derived from urothelial carcinoma. Case presentation: We present a unique case of a 76-year-old man with a recurrent urinary bladder tumor, initially interpreted as a high grade urothelial carcinoma with glandular differentiation. In the recurrent tumor, diverse histological patterns were identified, including glandular, hepatoid and sarcomatoid. This tumor showed positivity for AFP, GLP3 and SALL4, and negativity for CK7 and EMA. Fluorescent in situ hybridization study showed a polysomic pattern of chromosome 12. All these findings led to the final diagnosis of a Yolk sac tumor derived from urothelial carcinoma. Conclusions: Somatically derived Yolk Sac tumors should be considered in the differential diagnosis of a high grade urothelial carcinoma, particularly when glandular and other unusual patterns are observed. Key words: Yolk sac tumor, somatically derived, urothelial carcinoma, urinary bladder, case report.

Metastatic Melanoma to the Urinary Bladder of Ocular Origin Accompanied with Primary Cutaneous Melanoma: Diagnostic Challenge—A Report of a Case

Metastases of melanoma to the urinary bladder are infrequent. Even rarer are metastases to the urinary bladder from uveal melanoma, with only 3 cases published in the literature so far. Herein we present a case of a 77-year-old male patient who presented with metastatic melanoma to the urinary bladder. The patient’s history included the diagnoses of uveal melanoma treated with radiation 25 years ago, as well as that of cutaneous melanoma diagnosed 7 years ago. The molecular study of the urinary bladder tumor specimen identified mutation of the GNAQ gene, which has been suggested to be an early molecular event in the pathogenetic course of over 80% of uveal melanomas. Therefore, the diagnosis of uveal melanoma metastatic to the urinary bladder was made.