Extranodal natural killer/T-cell lymphoma (nasal type) presenting as a perianal abscess: A case report

BACKGROUND Extranodal natural killer (NK) T-cell lymphoma (ENKTL), nasal type is a rare subtype of extranodal non-Hodgkin lymphoma characterized by vascular damage and necrosis. The lesions usually present in the nasal cavity and adjacent tissues, however, the disease originates from the gastrointestinal or genitourinary tract in 25% of cases. Since rectal involvement in ENKTL is rare, rectal symptoms in the course of ENKTL are often misdiagnosed and considered to be related to benign diseases such as rectal fistula or perianal abscess. CASE SUMMARY We report the case of a 24-year-old Han Chinese female who initially presented with a perianal abscess that was subsequently diagnosed as nasal type ENKTL. Due to typical perianal pain, perianal abscess was diagnosed and surgical incision and drainage were performed. After recurrent, severe anal hemorrhages leading to hypovolemic shock and multiple surgeries, a diagnosis of ENKTL was made. The patient's condition gradually deteriorated, and she died shortly after initiation of chemotherapy. CONCLUSION Systemic and neoplastic diseases should be included in the differential diagnosis of any potentially benign perianal abscess complicated with recurrent hemorrhages.