A solitary fibrous tumor (SFT) is a mesenchymal neoplasm of spindle cells, initially described in the pleura. The World Health Organization (WHO) classifies the solitary fibrous tumor as a neoplasm with intermediate biological potential. Diagnostic images are essential for the diagnostic and therapeutic approach in this entity. The standard of treatment for this type of lesion is surgical resection with oncological margins larger than 1 cm. The solitary fibrous tumors located in the perianal, perineal, and pelvic regions are infrequent and represent a challenge in the clinical approach, mainly because the manifestations are nonspecific. Given the low incidence of this type of neoplasm, we present two cases of SFT in the perianal region managed in a high-complexity hospital.

A case of ischaemic strangulation of the small intestine caused by a haemangiopericytoma in a 12‐year‐old horse is reported. An encapsulated, 4‐cm diameter mass was located in the mesentery adjacent to the wall of the ileum resulting in an ileal obstruction and a subsequent small intestinal volvulus. Surgical management of the case was performed and the horse was discharged from the hospital with no further complications and no recurrence during a 2‐year follow‐up period. After histopathological and immunohistochemical evaluation, the mass was characterised as a haemangiopericytoma. The only report of a haemangiopericytoma in a horse describes a mass located in the eyelid. In humans and dogs, haemangiopericytomas can be malignant with local recurrences after excision and metastasis. In our case, the tumour caused severe ileal obstruction, but no distant metastases were found, and there were no clinical signs of recurrence for a 2‐year follow‐up period after surgery.

Se presenta el caso de una mujer joven con hallazgo endoscópico incidental en una colonoscopia de seguimiento, que consistía en una lesión en el ciego con histología benigna. Se describe el proceso diagnóstico y el tratamiento quirúrgico. Se revisa la literatura existente y se discuten la incidencia, el cuadro clínico y las indicaciones de tratamiento quirúrgico de una patología rara de baja aparición.

Se presenta el caso clínico de un paciente masculino, con clínica y hallazgos tomográficos de masa abdominal en colon descendente. Se describe proceso diagnostico y tratamiento. Se realiza revisión de la literatura, estableciendo su definición e indicaciones quirúrgicas, teniendo en cuenta que el divertículo gigante verdadero del colon se una entidad rara, con menos de 200 casos reportados en la literatura.