Plasmablastic lymphoma associated to Crohn's disease and hepatitis C virus chronic infection.

Plasmablastic lymphoma is a very rare and recently-described subtype of diffuse large B-cell lymphoma. It has a poor prognosis despite intensive chemotherapy treatment. A 57-year old woman with perianal Crohn's disease receiving azathioprine and infliximab developed this type of lymphoma after a short period of time on the treatment. She also had a hepatitis C virus chronic infection which had not been diagnosed or treated before. There is no solid scientific evidence that either immunomodulators or anti-TNF drugs have a definitive role in the appearance of malignancies, and therefore there are no clear recommendations to limit their use. In these patients, there are some other factors we have to take into account, like the inflammatory bowel disease in itself and its behaviour over time, or the comorbidities of the patient, with special attention to virus infections. In this case report, we will analyse the role of these factors in the development of lymphoproliferative disorders and the recommendations given by experts to avoid their appearance.

[Granular cell tumor of the esophagus: description of an infrequent benign tumor]. / Tumor esofágico de células granulares: descripción de un tumor benigno poco frecuente.

Granular cell tumors (GCT) are infrequent tumors first described by Abrikossoff in 1926. Gastrointestinal involvement occurs in about 6% of GCT, the esophagus being the most frequent location. These tumors are usually benign and asymptomatic and are usually found incidentally when an upper gastrointestinal endoscopy is carried out for another reason, showing an isolated polyp or sessile submucosal nodule, covered by intact yellowish mucosa and with firm consistency. Endoscopic ultrasonography has significantly improved the diagnosis of these lesions. Nowadays endoscopic mucosectomy is the treatment of choice of esophageal GCT with a low frequency of complications. Histologic analysis of the surgical specimen shows specific characteristics such as positivity for S-100 protein. We present two new cases of esophageal GCT that were diagnosed recently and discuss the most relevant features of this infrequent disease.

[Colorectal melanoma: review of two distinct forms of presentation]. / Melanoma colorrectal: revisión de dos formas diferentes de presentación.

Malignant melanoma of the colon and rectum is an infrequent disease. Primary anorectal melanoma accounts for 0.1-4.6% of all malignant neoplasms of the anal canal. Melanoma metastatic to the colon is symptomatic only in 4.4% of patients with a primary melanoma at another site and most of these tumors are diagnosed postmortem. We report two cases of colorrectal malignant melanoma. The first case concerned a patient with rectal bleeding who was diagnosed with a rectal lesion compatible with melanoma. Abdominoperineal resection was performed due to positivity of the sentinel lymph node. We discuss the utility of sentinel lymph node detection in this kind of tumor. In the second case, we discovered a polyp compatible with metastatic melanoma in the transverse colon in a patient with a previous diagnosis of melanoma. In both surgical specimens, the diagnosis of melanoma was confirmed by positivity for protein S-100, Melan-A and HMB-45.