Discussion and Conclusions
In this study we present a unique case of mucinous appendiceal neoplasm
that invaded from intraperitoneum to retro peritoneum. To our knowledge,
this is the first case study that tumor had perforated (invaded)
visceral peritoneum into the retroperitoneum.
Park et al reported a 32-year-old man with extra-GIST (EGIST) who
referred to the hospital with dysuria and abdominal mass. Preoperative
ultrasound and MRI revealed a lobulated mixed echoic mass in the
retroperitoneum with heterogeneous enhancement. Patient underwent
surgical excision of tumor and a low anterior resection because of
invasion to the wall of the rectum.(7) In our case also no adhesion
around tissue was found but tumor extends inferiorly to the right side
of the lower abdomen and pelvic cavity.
Engin et al. reported case of GIST with mesenteric and
retroperitoneal invasion, also entered the
small bowel serosa, colonic submucosa and the left ureter which
presented with abdominal bulging , weight loss , and hematuria (6) . It
is inconsistent with our patient, but in general, it can be concluded
that penetration of tumors to visceral peritoneum can be due to the
weakness of this layer.
Mucinous appendiceal neoplasms are rare, but necessary to detect with
imaging due to their malignant potential. Peritoneal seeding and
pseudomyxoma peritonei can occur in both malignant and low-grade
appendiceal neoplasms(9).
Regardless of their clinical seriousness, mucinous neoplasms may be
challenging to diagnose since the symptoms are usually mild or
nonspecific. They often present with stomach pain, weight loss, nausea,
fatigue, a palpable mass, and acute appendicitis. Roma et al .
report a late stage diagnose of apendiceal mucinous adenocarcinoma with
rare presentation such as scrotal pain, abscess, and inguinal drainage
(10) but our patient developed with typical symptoms like abdominal
pain, weight loss and palpable mass without any appendicitis alarm.
In conclusion ,due to the non-specificity of the symptoms, when patient
develops with abdominal distention , pain and retroperitoneal mass , we
should consider invasion of intraperitoneal tumors such as appendiceal
tumors while precise surgical management of these neoplasms may avoid
delay in diagnosis and/or complications of peritoneal seeding.