S2434 Post Liver Transplant Appendicitis: Be Vigilant for Appendiceal Tumors!

Abstract

INTRODUCTION: De novo malignancies in post-transplant patients are a sequel of immunosuppression and have an incidence between 3 and 26%. They are one of the most common cause of morbidity and mortality in long term survival of liver transplant patients with risk almost four times greater than general population. While case reports of appendiceal tumors have been documented in renal transplant patients, there is not much literature for liver transplant patients. Also, fewer than 30 cases of appendicitis in post liver transplant setting have been reported in literature till date. We present a very rare case of mucinous appendiceal adenocarcinoma that presented as appendicitis within three years of liver transplant. CASE DESCRIPTION/METHODS: A 32-year-old Caucasian female with decompensated autoimmune cirrhosis underwent liver transplant in 2017 after detailed transplant evaluation. Post-transplant she was kept on protocol-based immunosuppression consisting of tacrolimus, mycophenolic acid and prednisolone with acceptable therapeutic drug monitoring. She presented in June 2019 with acute onset abdominal pain and was diagnosed with acute appendicitis on clinical examination and imaging. A laparoscopic appendicectomy was performed but complicated by intra-operative appendiceal rupture. Postoperative course was uneventful. Interestingly, final pathology revealed low-grade appendiceal mucinous neoplasm. Considering mandatory immunosuppressive state and peritoneal rupture of appendiceal malignancy, with extensive literature review and team discussions, patient underwent right hemicolectomy followed by intra-operative hyperthermic intraperitoneal chemotherapy (HIPEC) in July 2019. The patient recovered well with no disease recurrence till her last follow up on May 2020. DISCUSSION: Appendiceal malignancies are difficult to diagnose and found in 2% of appendectomy specimens. Mucinous appendiceal cancers are an even rarer subset with incidence of only 0.2%. The reported survival rate is <10% over 10 years. It is extremely rare for GI malignancy to present within 3 years of transplant since detailed cancer screening is part of transplant evaluation which includes abdominal imaging and colonoscopy. Here we report early presentation of a very rare appendiceal carcinoma in post liver transplant setting with excellent response to right hemicolectomy and HIPEC despite continued immunosuppression, which has never been reported. The case also stresses the need for detailed cancer screening in this special population.