Case provided by Manuela
50 years old female with known ovarian cancer and peritoneal carcinomatosis coming with nausea and vomiting a few days after chemotherapy. Surgical resection had included parts of the colon and had ended up in a colostomy, which had to be revised because of an impacted parastomal hernia two years ago.
CT (images A and C) and MRI (images B and D) show a fluid distended stomach (stars in A and B) and a fluid retention in the lesser sac (arrow heads in A and B) compressing the stomach so that the gastric passage is obstructed. Peritoneal carcinomatosis is furthermore represented by diffuse thickening of the visceral peritoneum encasing the small intestine (closed arrows in C and D) and diffuse infiltration of the small intestine mesentery (open arrows in C and D). The latter phenomenon produces the so called impression of a „stellate mesentery“.
Peritoneal carcinomatosis of ovarian cancer with gastric outlet obstruction by a fluid collection in the lesser sac and intestinal encasement by diffuse serosal seeding and mesenteric infiltration.
As in our case, two thirds of patients are in progressed stage of disease (FIGO IIIC or IV) when ovarian cancer is diagnosed for the first time. Even in progressed stage surgery is the most important therapy. Tumor debulking aiming at macroscopic cytoreduction is important, which mostly means bilateral salpingo-oophorectomy, omentectomy, systematic lymph node dissection, and peritonectomy procedures, if necessary. Sometimes it is necessary to remove some parts of the colon, often associatied with a colostomy. Studies show that a colostomy can increase the mean survival of patients for a few months compared to those patients who underwent resection of colon without a colostomy. Prognosis is dependent on the succes of cytoreduction.
In ovarian cancer peritoneal carcinomatosis develops due to spreading of tumor cells with ascites. The locations peritoneal tumor implants develop correlate with the physiology of peritoneal fluid circulation and with the anatomy of peritoneal ligaments. Preferred sites of peritoneal tumor implants are the subphrenic spaces, the paracolic gutters, the ileocolic junction, the mesosigmoid, the greater omentum, and the mesentery of the small intestine. Patterns of peritoneal carcinomatosis include nodular lesions, plaque-like lesions, and diffuse infiltration of mesenteric fat.
Bowel obstruction ist the most important complication of peritoneal carcinomatosis. It may be the result of tumor seeding along the visceral peritoneum and encasing the small intestine. It may also be secondary to ascites trapped between encased bowel loops or, as in our case, in predefined spaces such as the lesser sac.
- Ovarian carinoma is often diagnosed for the first time in progressed stage when peritoneal carcinomatosis already exists.
- Sites of peritoneal tumor implants correlate with the physiology of ascites circulation and anatomy of peritoneal ligaments.
- Ileus in peritoneal carcinomatosis may be secondary to tumor implants directly obstructing the intestinal passage or to ascites trapped in encased bowel loops or predefined peritoneal spaces.
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The Role of Bowel Surgery with Cytoreduction for Epithelial Ovarian Cancer
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What the Radiologist Should Know About Treatment of Peritoneal Malignancy
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