Vague abdominal pain, malaise, anorexia,
and the loss of 10 lb in 2
months prompted a 65-year-old man
to seek medical evaluation. A year
earlier he had undergone surgery for
stage III carcinoma of the sigmoid
colon. Because metastases to the
lymph nodes were found in the resected
colon, the patient was given postoperative
examination revealed poorly differentiated
Mild diffuse abdominal tenderness was the only significant
physical finding. Laboratory test results revealed
mild anemia and a markedly elevated carcinoembryonic
antigen (CEA) level. A CT scan of the abdomen and pelvis
showed enhancing, multiple, small nodules along the anterior
abdominal peritoneal surface (A, arrows) and irregular
thickening of the omentum (B, arrows). Results of a
colonoscopy were unremarkable. Widespread peritoneal
carcinomatosis was diagnosed.
Despite improvements in perioperative mortality and
overall survival for patients who undergo resection for colorectal
cancer, the disease can recur.1 The risk of recurrence
is dependent on the cancer's stage and site; additional
risk factors include:
- The presence of a malignant obstruction.
- Poor cell differentiation on histologic examination.
- Mucin production by the tumor cells.
- Lymphatic and vascular invasion by cancer cells.
Most recurrences are within 2 to 3 years after the
original cancer surgery and involve the original site or
such organs as the liver, lungs, and bone.
Peritoneal carcinomatosis involves widespread diffuse
metastases to the peritoneal surfaces. The prognosis is
extremely poor. Physical examination is not elucidating unless
the patient has bowel obstruction or ascites. An elevated
CEA level and characteristic CT findings--such as
enhancing nodules, a soft tissue mass along the peritoneal
surfaces, and ascites--aid in making the diagnosis. Omental
involvement may be depicted on CT scan as a solid
mass (described as an omental cake) or multiple, small,
ill-defined, solid nodules scattered throughout the omentum,
which cause a thickened or smudged appearance.
Malignant tumoral seeding of
the peritoneum most frequently originates
from primary ovarian, colonic,
and gastric cancers. Less common
primary sites include the pancreas,
uterus, and bladder.
This patient received palliative
chemotherapy. He died of the disease
4 months later.