Clinicopathological characteristics and outcome of nested carcinoma of the urinary bladder.

We present the clinicopathological features of 56 cases of the nested variant of urothelial bladder carcinoma. This is an uncommon variant of bladder cancer, recognized by the current WHO classification of urologic tumors. The nested component represented 100 % of the tumor in 24 cases. The architectural pattern of the tumor varied from solid expansile to infiltrative nests characterized by deceptively bland histologic features resembling von Brunn nests. Typical features of high-grade conventional urothelial carcinoma were present in 32 cases. Most neoplastic cells had nuclei of low to intermediate nuclear grade with occasional nuclear enlargement, most frequently seen in deep areas of tumor. The nested component expressed cytokeratins 7, 20, CAM5.2, and high molecular weight (34ßE12), p63, Ki67, p53, p27, and GATA3. Tumor extension was T1 (n = 9), minimally T2 (n = 10), T2a (n = 1), T2b (n = 4), T3a (n = 8), T3b (n = 13), and T4a (n = 11). On follow-up, 36 of patients died of or were alive with disease from 2 to 80 months (mean 21 months). Four patients died of other causes. Eleven other patients remained disease free. Univariate survival analysis showed no differences for nested carcinoma compared with conventional urothelial carcinoma. As in conventional urothelial carcinoma, in nested carcinoma of the bladder pT category defined different survival groups. In summary, nested variant of urothelial bladder carcinoma is typically associated with advanced stage. In samples of limited volume, it may be misdiagnosed as proliferation of von Brunn nests or other nested-like bladder lesions, delaying definitive therapy.

Flat urothelial carcinoma in situ of the bladder with glandular differentiation.

We present the clinicopathologic and immunonohistochemical features of 25 cases of flat urothelial carcinoma in situ with glandular differentiation. Previously, cases on this category have been reported as in situ adenocarcinoma (a term not currently preferred). Fourteen of 25 cases had concurrent conventional urothelial carcinoma in situ. Five of the cases were primary carcinoma in situ with glandular differentiation; twenty cases of secondary carcinoma in situ with glandular differentiation were associated with urothelial carcinoma alone (n = 11) or with glandular differentiation (n = 7), discohesive (n = 1) or micropapillary carcinoma (n = 1). The individual tumor cells were columnar. The architectural pattern of the carcinoma in situ with glandular differentiation consisted of 1 or more papillary, flat or cribriform glandular patterns. Univariate statistical analysis showed no survival differences between urothelial carcinoma in situ with glandular differentiation and conventional urothelial carcinoma in situ (log-rank 0.810; P = .368). Carcinoma in situ with glandular differentiation showed high ki-67 index and p53 accumulation, high nuclear and cytoplasmic p16 expression and diffuse PTEN expression, a phenotype that also characterized concurrent conventional carcinoma in situ. MUC5A, MUC2, CK20, and c-erbB2 were positive in all 25 cases of urothelial carcinoma in situ with glandular differentiation, and CDX-2 was present in 19 cases; MUC1, CK7, or 34ßE12 was focally present in 21, 19, and 18 cases, respectively. MUC1core was negative in all cases. We concluded that urothelial carcinoma in situ with glandular differentiation is a variant of carcinoma in situ that follows the natural history of conventional urothelial carcinoma in situ. The immunophenotype suggests urothelial origin with the expression of MUC5A and CDX2 as signature for glandular differentiation.

Large cell undifferentiated carcinoma of the urinary bladder.

We present the clinicopathological features of eight cases of large cell undifferentiated bladder carcinoma not otherwise specified (LCUBC). LCUBC was characterised by sheets of large polygonal or round cells with moderate to abundant cytoplasm and distinct cell borders. The LCUBC component varied from 90 to 100% of the tumour specimen with five cases showing pure LCUBC. The architectural pattern of the tumour varied from infiltrating tumour to solid expansile nests with focal (<5%) discohesive growth pattern in two cases. Immunohistochemical staining demonstrated that LCUBC cases were positive for cytokeratins AE1/AE3 and 7; CAM 5.2, CK20, thrombomodulin and uroplakin III were positive in six, three, three and two cases, respectively. Other immunohistochemical markers performed in the differential diagnosis context included alpha-fetoprotein, beta human chorionic gonadotrophin (betahCG), prostate specific antigen (PSA), vimentin, synaptophysin and chromogranin and all were negative. Ki-67 and p53 labelling indexes were 50-90% and 40-90%, respectively. All patients had advanced stage cancer (>or=pT3) and seven (87.5%) had lymph node metastases. Follow-up information was available in all cases, with a range of 6-26 months (mean 10.6 months). Six patients died of disease between 5 and 26 months and two patients were alive with metastases at 6 and 14 months. The prognosis of LCUBC was compared with conventional urothelial carcinoma of similar stages showing survival differences (p =0.0004). In summary, LCUBC is an aggressive variant of urothelial carcinoma that presents at an advanced stage.

Fine needle aspiration cytology of focal myositis: a case report.

BACKGROUND: Focal myositis is an unusual inflammatwy lesion of the skeletal muscle first described by Heffizer. It is a benign condition and usually involves the muscles of the limbs. CASE: A man presented with a palpable mass in the left leg of 6 months' duration. Nuclear magnetic resonance of the leg showed a mass in the tibial muscle; the presumptive diagnosis was sarcoma of the muscle. Smears showed inflammatory cells, skeletal muscle fibers with degenerative and regenerative changes, and fibrous tissue, suggesting a diagnosis of focal myositis. An incisional muscle biopsy was performed, confirming the diagnosis. CONCLUSION: Focal myositis should always he considered when aspirating muscle masses because it is a clinical mimic of a neoplasm. The prognosis is good, and all cases reported in the literature were self-limiting and gradually resolved.