RESUMEN

In complex anal fistula, the patient's anus has multiple internal or external openings. The closure of the external opening can be broken again in other trips and another external opening. It is one of the refractory diseases in the field of anorectal surgery. In the treatment of a high recurrence rate, poor functional protection and other problems, surgical treatment such as incision and retention of sphincter hanging line, incision and suture internal opening drainage, fistula removal, and suture were used for different situations. After the failure of surgical treatment, it becomes chronic anal fistula or become cancerous tumor. In this case, the patient had a long time of illness, the mass was huge, the color was black, and it was suspected to be a secondary malignant tumor. This situation is extremely rare in clinical treatment. In our hospital, a case of complex anal fistula secondary to perianal huge tumor was found, and good therapeutic effect was achieved after complex anal fistula resection and tumor resection. In this case, the patient had complex anal fistula for about 5 years without timely treatment, and the perianal mass was rare and huge. It is shown by ultrasonography the secondary malignant tumor, which was extremely rare in clinical treatment. During the operation, it was found that three fistulas at the root of the tumor were connected with one of the anal fistulas. From the appearance, the tumor seems to have a malignant tendency. After surgical resection, the pathology was suppurative inflammation and granulation tissue hyperplasia. The patients recovered well after follow-up and did not relapse. This case report provides case reference and reference for clinical treatment of anorectal diseases.