Objective: Osteoblastoma is a rare benign osteoblastic tumor with a potential for local bone destruction and aggressiveness. The most common site of osteoblastoma is the vertebral column particularly the posterior elements and the sacrum. Method: In this study we present nine cases of osteoblastoma and the principal differential diagnosis. Results: On a period of 10 years, nine cases of osteoblastoma had been diagnosed including seven males and two females. The age of those patients ranged from 5 to 29 year old. The tumor was localized in the spine in five of the nine cases and the other ones in the long bones. The radiological diagnosis of osteoblastoma was made in just two cases. The diagnosis was made by histology in eight cases. All our patients had been treated with curettage. On the nine patients, just one of them had developed two successive recurrences. Conclusion: Osteoblastoma is a rare benign tumor which is rarely diagnosed by radiology alone. The pathologist should always suspect an osteoblastoma in front of a vertebral localization of any tumor. Objective: Congenital hepatic fibrosis (CHF) is a developmental disorder of the portobiliary system. Clinical findings usually include enlarged liver, well-preserved hepatocellular function and portal hypertension. CHF is frequently associated with hepatorenal fibrocystic disease. Method: A 29-year-old woman was referred to our hospital for further evaluation of hepatomegaly, and portal hypertension was found. Laboratory tests were all negative. MRI identified hepatosplenomegaly with hypertrophic left medial segment, high uptake nodular areas and homogeneous boundary liver. Needle biopsy was performed. Results: The biopsy demonstrated slight portal fibrosis and fibrous septa with proliferation of numerous biliary ducts, some of them containing inspissated bile. It was also noticeable the few number of portal vein branches. There was no inflammation or hepatocyte necrosis. Therefore, our diagnosis was congenital hepatic fibrosis. We correlated these results with radiology. Magnetic resonance cholangiopancreatography showed peripherally dilated biliary intrahepatic branches contrasting with preserved caliber of main intrahepatic branches. These findings were also diagnostic for CHF. Conclusion: The low prevalence of CHF makes it hard to think about this entity in patients with portal hypertension and normal laboratory findings. The histological differential diagnosis must be done mainly with cirrhosis, but also with idiopathic portal hypertension and, in small biopsies, with biliary hamartoma. Results: A total of 97 cases of digestive tract lymphoma were reported (64 males, 33 females) with a sex-ratio of 2.0. The patient age ranged between 6 and 82 years with a median age of 48 years. Stomach location was the most frequent with 80 % of cases followed by intestine (15 %) and colon (5 %). Among the 97 digestive tract lymphomas, 48 % were of Marginal zone type (MALT) and 47 % were large B-cell lymphoma. According to the Ann Arbor staging system, 85 % of patients were diagnosed at stage I and II.