Brief Answer:
Possible inflammation or malignancy to be evaluated by colonoscopy biopsy

Detailed Answer:
Hi XXXXX,
Thanks for writing in to us.

I have read through your query in detail.
Please find my observations below.

1. The rectum is the distal end part of the large bowel. Diffuse wall thickening refers to a condition where there is a long segment of the rectum that shows wall thickening. Such a wall thickening might be regular or irregular.

2. There are inflammatory, benign and malignant conditions which might cause such features on CT scan.

3. In inflammatory conditions there is Crohns disease, colitis or proctitis in which there is diffuse rectal wall thickening. Benign tumors are less likely to appear as diffuse wall thickening.

4. Considering malignancies, there is rectal cancer, lymphoma and less likely a carcinoid. These require to be detected and confirmed by a biopsy.

5. It is suggested that you proceed with the detailed evaluation of rectal wall thickening and get a colonoscopy and probably biopsy done and confirm the conditions. Early diagnosis and treatmetn are curative in most malignancies.

Hope this answers your question. Please feel free to correct any oversight in my interpretation of your problems and discuss them in detail as per your requirements.

Hope your query is answered.
Do write back if you have any doubts.

Regards,
Dr.Vivek

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