Giant appendiceal mucocele: report of a case

High-grade appendiceal mucinous neoplasm presenting as a giant appendiceal mucocele

Appendiceal mucinous neoplasms are rare findings defined by an accumulation of mucus within the vermiform appendix, and can be caused by a variety of conditions. Appendiceal mucinous neoplasms are important to consider because they can develop into pseudomyxoma peritonei as a consequence of perforation. We report a case of a 55-year-old man who initially presented with increasing abdominal girth, constipation, anorexia, and unintentional weight loss. Computed tomography examination of the abdomen and pelvis demonstrated a huge thin-walled cystic mass causing significant displacement of the surrounding abdominal and pelvic structures. The mass was amenable to resection and removed without perforation. Gross pathologic examination demonstrated a 44.0 × 40.0 × 23.0 cm unilocular cystic mass with a section of attached bowel. Microscopic examination revealed high-grade appendiceal mucinous neoplasm arising in a background of low-grade appendiceal mucinous neoplasm. This case report provides an evidence to include appendiceal mucinous neoplasms in the differential diagnosis of large abdominal cystic masses.

[Management of mucinous tumor of appendix]

Low-grade mucinous tumors (MT) of the appendix are rare malignancies. One of the most formidable complications of these tumors is mucin depositing in the peritoneum with development of peritoneal pseudomyxoma. Currently, there are no single clinical - pathomorphological classification and treatment approach to these tumors. This situation is complicated by the fact that tumor of the appendix cannot be preoperatively suspected in many cases and MT is detected after appendectomy for acute appendicitis or its complications. Thus, prognosis of patients is deteriorated.

A Case of Strangulation Ileus Due to a Low-Grade Appendiceal Mucinous Neoplasm

BACKGROUND Strangulation ileus is caused by external obstruction to the small bowel, which results in ischemia and loss of bowel peristalsis. Low-grade appendiceal mucinous neoplasm (LAMN) is a low-grade adenocarcinoma that arises in the appendix. LAMN is usually asymptomatic but can present with appendiceal rupture and pseudomyxoma peritonei (PMP). This report is of a rare presentation of LAMN with strangulation ileus in a 92-year-old man. CASE REPORT A 92-year-old man was admitted to the emergency room with sudden onset of lower abdominal pain and abdominal distension. Laboratory investigations showed a leukocytosis with a white blood cell (WBC) count of 14.6×10³/μL with 85.5% neutrophils, blood urea nitrogen (BUN) of 26.6 mg/dL, and serum creatinine of 2.6 mg/dL, consistent with acute renal failure. Arterial blood gas analysis showed lactic acidosis (pH of 7.11) with a base excess of -20.8 mmol/L and lactate of 13.7 mmol/L. Abdominal computed tomography (CT) showed ascites and a dilated obstructed closed loop of the distal ileum associated with an external mass (3.9×2.8 cm). An initial diagnosis was of strangulation ileus due to Meckel's diverticulum. Emergency ileocecal resection was performed. Histopathology showed a low-grade mucinous tumor arising from the mucosa of the appendix, consistent with LAMN. At a 13-month follow-up, the patient was well with no tumor recurrence. CONCLUSIONS This report is of a rare case of LAMN that presented as a surgical emergency with strangulation ileus.

A Rare Case of Low-grade Appendiceal Mucinous Neoplasm: A Case Report

Low-grade appendiceal mucinous neoplasm (LAMN) is a rare malignancy with symptoms varying depending on the clinical manifestations. The most worrisome complication of this particular neoplasm is seeding of mucin into the adjacent peritoneum leading to pseudomyxoma peritonei (PMP). There is a lack of standardized treatment approach; however, an appendectomy-only approach is currently being used for the resection of non-metastatic disease. We present an unusual case of a 67-year-old male found to have LAMN status post elective appendectomy, six months after being treated for an appendiceal abscess.

A case report of a giant appendiceal mucocele and literature review

A 43-year-old female presented at the accident and emergency department of Princess Marina Hospital, Gaborone, Botswana. She reported a deep dull aching pain of two years duration in the right iliac fossa that has been progressively becoming worse. Ultrasound revealed a large sausage like cystic mass extending from the pelvis up to the medial aspect of the ascending colon. CT scan showed a large sausage like cystic mass extending from the pelvis up to the hepatic flexure of the colon with the cecum displaced. No metastatic features were seen. We made an impression of appendiceal mucocele. A semi-elective laparotomy was scheduled. Intraoperative findings: a giant intact cystic distended appendix with involved base, displacing the cecum cranially. A right hemicolectomy was performed. The histopathological results revealed a low-grade appendicular mucinous neoplasm with no lymph node involvement. The surgical margins were free. The patient recovered uneventfully.

Incidentally discovered low-grade appendiceal mucinous neoplasm: a precursor to pseudomyxoma peritonei

Appendiceal mucoceles (AMs) infrequently arise from an underlying malignancy. Treatment has progressed toward a less aggressive approach over time; they can be managed by appendectomy-only unless pathology reveals malignancy. The ultimate goal of management is to prevent AM rupture, avoiding the syndrome of pseudomyxoma peritonei.