A 47-yr-old man suffering from tenesmus and mucoid stool was admitted to our hospital via a local clinic. He had smoked one pack of cigarettes daily for 20 yr and he did not drink alcohol. He had a history of pulmonary tuberculosis 20 yr ago that was treated with anti-tuberculosis medication for 9 months. On admission, he appeared in good health without any complaints of weight loss, fever and night sweats. His blood pressure was 110/90 mmHg, his pulse rate was 78/min, body temperature was 36.2C and respirations were 18/min.
On physical examination, the patient appeared normal and showed no remarkable findings except a depressed anterior chest wall. No lymphadenopathy was detected. His breath sounds were clear and his heart sounds were regular without any murmurs.
The laboratory findings included hemoglobin 13.4 g/dL, white blood cells 4,600/microL, platelets 305,000/microL, AST 22 IU/L, ALT 35 IU/L, ALP 47 IU/L, GGT 42 IU/L, LDH 393 U/L, BUN 14.8 mg/dL, creatinine 1.0 mg/dL, uric acid 6.2 mg/dL and calcium 3.6 mg/dL.
A radiograph of the chest showed a white lesion in the right upper lung field; this was thought to be a healed scar from pulmonary tuberculosis.
The upper gastrointestinal endoscopic examination revealed an healed ulcer in the duodenal bulb. Rapid urease test for Helicobacter pylori gave a negative result. Colonoscopic examination revealed two lesions 1) a granular & reddish mucosal thickening at the just above rectum (Fig. 1A), and 2) a reddish inflammatory mucosa without elevation or depression at the appendiceal orifice (Fig. 1B). Microscopic examination of the mucosal lesions of the colon and rectum showed lymphoepithelial lesions consisting of diffuse proliferation of small lymphocytes and some glandular destruction by lymphocytes (Fig. 2A). Immunohistochemistry showed the neoplastic cells were positive for CD20 (Fig. 2B) but negative for CD5, CD10, and cyclin D1. We then started to perform the staging evaluation of non-Hodgkin's lymphoma (NHL). The titer of beta2-microglobulin was 1,770 microg/L and this was in the normal range. The proteins showed a pattern of polyclonal gammopathy upon serum protein electrophoresis. Computed tomography of abdomen revealed no lymphadenopathy. A bone marrow aspiration and biopsy was performed and they revealed no remarkable findings.
He was diagnosed with a low grade MALT lymphoma of stage IE (using Ann-Arbor staging) and stage II (using St. Jude Children's Research Hospital staging). He had received anticancer chemotherapy (cyclophosphamide 1,200 mg, adriamycin 80 mg, vincristine i.v. and prednisolone 100 mg p.o. for 5 days every month for 4 months) with involved field radiation therapy (3,000 cGy at the colon and 150 cGy at the rectum with 10 MV radiography 2 ports for 20 times during 29 days).
His presenting symptoms, including the tenesmus and mucoid stools subsided after treatment. Three months after treatment, a follow-up colonoscopy revealed no abnormal mucosa (Fig. 3).