Discussion Author: Albert V Porambo
Read more about Adenocarcinoma of the rectum
Multiple CT images of the rectum and sigmoid colon demonstrate eccentric nodular wall thickening along with mild haziness of the border between the bowel wall and the surrounding fat.
Differential considerations include colonic neoplasms such as a villous adenoma, the so-called â€ścarpet lesionâ€ť, adenocarcinoma, stromal cell tumor; carcinoid; hematoma; lymphoma; and metastases.
In this patient, who presented with rectal pain and bleeding sigmoidoscopy and a biopsy was performed, and invasive, moderately differentiated, colonic adenocarcinoma was detected.
Colorectal carcinoma remains the most commonly diagnosed malignancy behind prostate, breast and lung cancer. The incidence of colon cancer is approximately 2.5 times that of rectal cancer. Inflammatory bowel disease, and in particular, ulcerative colitis, carries a greater risk for the development of colorectal cancer.
The radiologic findings of colorectal cancer include a number of appearances. These include, but are not limited to, round polypoid filling defects to encircling, constricting lesions. They can be seen as raised, ulcerated masses, or as irregular, villous appearing lesions. Frequently CT evaluation of the abdomen reveals a soft-tissue mass adjacent to or within the colonic lumen. One must look or evidence of extension of the tumor beyond the wall, or involvement of adjacent organs, such as lymph nodes or distant spread, with the liver being the most common site for hematogenous spread. On CT, pericolonic soft tissue infiltration can represent local tumor extension or secondary inflammation. Overall, CT has a relatively low accuracy rate for preoperative staging, ranging from 50-75%. Difficulties arise from predicting the degree of mural extension, involvement of normal sized nodes, and detection of small peritoneal deposits. Transrectal endosonography has been shown to be a potentially useful technique in the evaluation of the spread of rectal cancer into the perirectal soft tissues. Early reports suggest it is more accurate then CT in evaluating the extent of invasion.
This lesion was staged as stage III, as there evidence of bowel wall penetration, and a tiny lymph node present. It will be managed with presurgical radiation therapy and chemotherapy to reduce the risk of local recurrence.
Search for more about Adenocarcinoma of the rectum