A Journey From Appendicitis to a Rare Appendiceal Mucinous Neoplasm

We present here a 66-year-old Caucasian male whose persistent abdominal pain thought to be due to appendicitis and associated acute splanchnic thrombosis. He was initially managed with antibiotics and anticoagulation. But further work up revealed a low-grade appendiceal mucinous neoplasm causing the splanchnic vein thrombosis. Additionally, diagnosis and management of this rare tumor and appropriate work up for splanchnic thrombosis will be briefly reviewed here.

Low grade appendiceal mucinous neoplasm metastatic to the ovary: A case report and intraoperative assessment guide

INTRODUCTION

Incidence of low grade appendiceal mucinous neoplasm is increasing. Preoperatively, it may present similarly to primary ovarian malignancy. This case report describes a case of presumed ovarian malignancy with final pathologic diagnosis of low grade appendiceal mucinous neoplasm. We also propose several surgical strategies to approach this conundrum.

PRESENTATION OF CASE

A postmenopausal woman with abdominal pain was found to have a 30 cm abdominopelvic mass with elevated CA-125 and CEA presumably a primary ovarian malignancy. During surgical staging, intraoperative findings were notable for an appendiceal mass. Intraoperative surgical oncology consultation recommended appendectomy for diagnostic purposes. Following primary surgery and final pathologic diagnosis, she underwent cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

DISCUSSION

Low grade appendiceal mucinous neoplasm should be within the differential diagnosis of gynecologic surgeons when presented with a patient with large volume ascites and biopsy of acellular mucin. Intraoperatively, an abnormal appearing appendix with normal appearing gynecologic structures should trigger suspicion for appendiceal rather than ovarian origin. Preoperative symptoms, imaging studies, tumor markers, and frozen section pathology may not be able to differentiate between appendiceal and epithelial ovarian malignancies.

CONCLUSION

A recognition of mucinous material and abnormal appearing appendix should prompt the surgeon to consider performing an appendectomy to obtain primary pathologic diagnosis. A high level of suspicion could better optimize the patient for a joint case with the appropriate surgeons. Given the documented disguise of low grade appendiceal mucinous neoplasm as primary ovarian cancer and its increasing incidence, diagnosis and general understanding of treatment should be understood.

Progression to pseudomyxoma peritonei in patients with low grade appendiceal mucinous neoplasms discovered at time of appendectomy

BACKGROUND

The discovery of a low grade appendiceal mucinous neoplasm (LAMN) during appendectomy is a rare scenario. These neoplasms can progress to pseudomyxoma peritonei (PMP), however the incidence of progression is not well known.

METHODS

The records of all patients with a diagnosis of localized LAMN found during appendectomy were identified, and demographic, tumor, surveillance, and outcome variables were analyzed.

RESULTS

Progression to PMP occurred in 20% of patients in an average of 12.4 months after appendectomy with median follow-up of 18 months. Tumor variables such as margin positivity, appendiceal perforation, and presence of extra-appendiceal acellular mucin or mucinous epithelium on the serosal were not significantly associated with progression.

CONCLUSIONS

During an average follow-up period of 18 months after surgery, progression to PMP occurred in a fifth of patients. It is difficult to predict which patients will progress, therefore cross-sectional imaging surveillance is recommended for all patients.

Management of an inguinal hernia in patients with pseudomyxoma peritonei

BACKGROUND

Pseudomyxoma peritonei is a disease that results from a perforated mucinous neoplasm of the appendix so that mucinous ascites and mucin-producing tumor cells are widely disseminated in a characteristic pattern throughout the abdomen and pelvis. The intraabdominal mucus can accumulate in the inguinal canal and by physical examination be indistinguishable from the usual inguinal hernia.

METHODS

A database of patients with pseudomyxoma peritonei was used to identify patients who had an inguinal hernia prior to or at the time of cytoreductive surgery (CRS) and perioperative hyperthermic chemotherapy (HIPEC). At the time of CRS, care was taken in all patients to remove the peritoneal lining of the inguinal canal. Patients who had the inguinal hernia repaired prior to definitive treatment with CRS and HIPEC had all tissue and mesh associated with prior herniorrhaphy resected.

RESULTS

In 178 pseudomyxoma peritonei patients, 17 had a new onset or previously repaired inguinal hernia that required extraction of mucus and mucinous tumor from the hernia site. No repair of the open inguinal canal was attempted at the time of CRS. No recurrent inguinal hernias were recorded and no patients required an inguinal incision at a later time to resect progressive disease within the inguinal canal.

CONCLUSIONS

Inguinal hernias caused by mucinous ascites and tumor were definitively treated by cytoreductive surgery plus HIPEC. Extraction of tumor and peritoneum from the inguinal canal facilitates fibrous closure of the hernia defect so that hernia recurrence was not observed.