San Ysidro Health/Scripps Mercy Chula Vista Hospital San Diego, CA
Andrew Bui, DO, Sharonya Shrivastava, MD San Ysidro Health/Scripps Mercy Chula Vista Hospital, San Diego, CA
Introduction: Appendiceal neoplasms are asymptomatic and non-obstructive that make up ~1% of appendectomy specimens and ~0.5% of intestinal neoplasms. We present an incidental finding of appendiceal neoplasm in a patient with an acute GI bleed.
Case Description/Methods: A 61-year old male with PUD and diverticulosis on colonoscopy (CLN) three years ago presented with painless hematochezia associated with a 3-month 30-lb weight loss. On presentation, vital signs were stable. Physical exam noted for mild abdominal distention. Laboratory values showed WBC of 17.2 K/mcL, hgb of 10.9 g/dL (from 15.1), MCV of 75 fL and platelet count of 1,126 K/mcL (normal one year ago). Computed tomography (CT) of the abdomen and pelvis with contrast revealed a 3.3 x 2.5 cm hyperenhancing mass near the ileocecal valve. GI was consulted for a CLN which showed diverticular bleeding, but no mass. He remained asymptomatic. A bone marrow biopsy showed hypercellularity with atypia and fibrosis most consistent with myeloproliferative neoplasm (MPN). Cytology for JAK-2 V617 mutation was positive and initiated on hydroxyurea for essential thrombocythemia (ET). Meanwhile his hgb continued to downtrend presumed from an acquired von Willebrand syndrome (VWD) and repeat CT scan on hospital day (HD) 5 showed no evidence of acute GI bleed but again showed the mass. On HD7 the patient had BRBPR and a hgb drop to 7.8. On repeat CLN, a mass was discovered intussuscepting in and out of the appendix. A I-123 MIBG Scan was positive in the RLQ with elevated chromogranin A level. Biopsies revealed a low-grade carcinoid tumor. He was discharged with a plan for future right hemicolectomy once platelets stabilized.
Discussion: Neuroendocrine tumors (NET), aka carcinoid tumors, are typically detected in the 5th decade of life. Around 1/5th of NETs are found to have an associated non-carcinoid tumor for which colorectal cancer is 25 to 50% of the cases. In our patient, it was discovered during CLN and imaging prompted by rectal bleeding. It is likely that his carcinoid tumor could have gone undiagnosed if not for his rectal bleeding. We hypothesized this was due in part to his bleeding disorder (acquired VWD) which is very prevalent in those with ET. The patient’s coexisting carcinoid tumor and MPN was also of interest as myelodysplastic syndrome can develop in 2% of patients with metastatic NET who were treated with peptide receptor radionuclide therapy thought to be due to myelotoxicity. Treatment of localized >2 cm appendiceal NET is right hemicolectomy.
Figure: After careful observation of the cecum, a mass inside the appendiceal orifice was seen intussuscepting in and out. A to F shows time lapse of events.
