Primary Anaplastic Lymphoma Kinase (ALK)-Negative Anaplastic Large Cell Lymphoma (ALCL) Presenting as Perforation Peritonitis: A Case Report and Management Principles.

Anaplastic large cell lymphoma (ALCL) has a characteristic feature that distinguishes it from the other types of non-Hodgkin lymphomas (NHLs) - the presence of a marker on its surface called CD30. It can be either cutaneous, systemic, or around breast implants. The systemic type of ALCL can be further classified based on the presence or absence of an abnormal protein, anaplastic lymphoma kinase (ALK), as ALK-positive or ALK-negative ALCL, respectively. We are presenting a case of a 35-year-old male who presented to the emergency department with an acute episode of abdominal pain. He underwent emergency laparotomy with ileal resection and anastomosis, as he was diagnosed with perforation peritonitis. Histological and immuno-histochemical reports of the specimen showed a lymphoproliferative lesion, and it helped reach the diagnosis of ALK-negative ALCL. ALK-negative ALCL can be diagnosed by using multidisciplinary investigation techniques, including radiological imaging, histopathological examination along with immunohistochemical staining. Prompt diagnosis helps in distinguishing ALK-negative ALCL from other lymphomas as well as solids tumors of the small bowel.