Patients diagnosed with lymphoma can register under the departments of Hematology or Oncology, as both departments can administer chemotherapy. However, radiation therapy can only be conducted in the Oncology department. Each hospital may have slightly different categorizations for departments and diseases. However, for a patient initially presenting with lymphoma, who has not yet been diagnosed and primarily shows symptoms of painless lymph node enlargement, they can register under General Surgery. After completing necessary examinations like an ultrasound, if lymphoma is suspected, a lymph node excision biopsy is usually performed in General Surgery.