[Metanephric stromal tumor: report of two cases and bibliographic review]. / Tumor del estroma metanéfrico: presentación de dos casos en adultos y revisión de la literatura.

OBJECTIVE: Metanephric Stromal Tumors (MST) are pediatric renal neoplasms not very common in adults. This study revises its classification, incidence and evolution and also some specific characteristics of the cases diagnosed in adults. METHODS: We present two cases of MST diagnosed in adults of 72 and 77 years old respectively. Abdominal pain due to a more than 4 Kg. mass was the initial presentation in both cases. The tumors were completely resected. Four and ten years after excision patients are alive without disease. RESULTS: Characteristic histologic features include a proliferation of fusocellular cells with alternating cellularity that imparts a nodular appearance and onion-skin cuffing around entrapped renal tubules or vascular structures. No mitoses or atypia was found but extensive necrosis and fibrosis were present. A majority of stromal cells were vimentine and CD-34 positive. Stains for CK and EMA highlighted entrapped native tubules. Both cases were previously classified as mesoblastic nephromas. According to the 2002 ONS classification of tumours of the urinary system, they have been revised and re-classified as MST CONCLUSION: MST are pediatric benign tumors exceptionally diagnosed in adults. Metanephric stromal tumors are divided into 3 categories based on the presence of epithelial cells, stroma and epithelial cells plus stromal. Complete excision is the treatment of choice and the prognosis is excellent.

[Inflammatory bowel disease and amyloidosis]. / Enfermedad inflamatoria intestinal y amiloidosis.

Secondary (AA) amyloidosis is a rare but serious complication of longstanding inflammatory bowel disease that can affect the patient's prognosis more than the underlying disease. Although early diagnosis of this complication is becoming more frequent, its effective treatment continues to pose a challenge to the clinician. We present two cases of Crohn's disease complicated by secondary amyloidosis after two years, and describe their outcome.

[Colonic spirochetes: an infrequent cause of adult diarrhea]. / Espiroquetosis colónica: una causa poco frecuente de diarrea en el adulto.

Large intestine infection due to spirochetes was described in 1967 and is mainly related to two pathogens, Serpulina pilosicoli and Brachyspira aalborgi. Clinically, infection presents as diarrhea and/or rectorrhagia and is more frequent among homosexuals. Its prevalence is difficult to estimate but significant differences have been described according to the socioeconomic level of the area studied. We describe three cases of diarrhea due to spirochetes, which are of interest due to the lack of published cases in Spain. Based on these cases, we describe the main characteristics (morphological, therapeutic, etc.) of this infection.

[Synchronous presentation of inverted papilloma with transitional carcinoma focus in right kidney pelvis and bladder urothelial carcinoma]. / Presentación sincrónica de papiloma invertido con foco de carcinoma transicional en pelvis renal derecha y carcinoma urotelial vesical.

We report a case with synchronous presentation of inverted papilloma (I.P) and transitional cell carcinoma of the right renal pelvis (pT2G1) associated to urothelial carcinoma on left lateral wall of the bladder (T1G2). Urothelial inverted papilloma is an uncommon, generally benign tumor that account for 2.2% of all urothelial tumors. Although the preferred location is the bladder (90%), above all in trigone and bladder neck, also can be located at the UUT "upper urinary tract" (7-8%) and urethra (3%). A close follow-up is recommended after conservative therapy, mainly endoscopic procedure, due to likelihood of recurrence and synchronous or metachronous association with transitional cell carcinoma.