From the Guidelines
Rectal thickening is a symptom that requires a thorough diagnostic workup to determine its underlying cause, which could be inflammatory bowel disease, rectal cancer, radiation proctitis, or infection, and treatment should be guided by the specific cause. The diagnosis of rectal thickening typically involves a combination of clinical evaluation, imaging studies (such as MRI or CT scan), and often a biopsy, as recommended by the ESMO clinical practice guidelines for diagnosis, treatment, and follow-up of rectal cancer 1. Common causes of rectal thickening include:
- Inflammatory bowel disease (particularly ulcerative colitis)
- Rectal cancer
- Radiation proctitis
- Infection Treatment depends entirely on the underlying cause, and it is crucial to undergo a complete diagnostic workup including colonoscopy with biopsy before starting any treatment. For inflammatory conditions, medications like mesalamine suppositories (1g daily), hydrocortisone foam (90mg daily for 2-3 weeks), or oral anti-inflammatory agents may be prescribed. If cancer is diagnosed, treatment may involve surgery, radiation therapy, chemotherapy, or a combination approach based on staging, as outlined in the guidelines for rectal cancer 1. Infectious causes would require appropriate antibiotics targeted to the specific pathogen. Radiation proctitis might be treated with sucralfate enemas (10ml of 10% suspension twice daily) or hyperbaric oxygen therapy in severe cases. The prognosis varies significantly depending on the underlying cause, with inflammatory conditions generally having better outcomes than malignancies. It is essential to note that increasing age, comorbidity, and decreasing functional reserves are associated with higher early postoperative mortality and worse toxicity from radiotherapy and chemotherapy in older patients, highlighting the need for a thorough assessment before treatment, as recommended by the guidelines 1. Additionally, the role of clinical examination and biochemical investigations in patients with suspected anorectal abscesses or rectal prolapse should be considered, as outlined in the WSES-AAST guidelines 1. However, the most recent and highest quality study, the ESMO clinical practice guidelines for rectal cancer 1, should guide the diagnosis and treatment of rectal thickening.
From the Research
Diagnosis of Rectal Thickening
- Rectal thickening can be caused by various conditions, including neoplastic, inflammatory, infectious, or ischaemic diseases 2.
- The diagnosis of rectal thickening can be made using computed tomography (CT) scans, which can show the thickness of the rectal wall 3.
- The pattern of attenuation on CT scans, along with clinical findings, can help narrow down the differential diagnosis 2.
- Focal, irregular, and asymmetrical thickening of the bowel wall suggests a malignancy, while regular, symmetric, and homogeneous wall thickening is more frequently due to benign conditions 2.
Treatment of Rectal Thickening
- The treatment of rectal thickening depends on the underlying cause of the condition 4.
- If the cause is benign, treatment may involve managing symptoms and monitoring the condition 4.
- If the cause is malignant, treatment may involve surgery, chemotherapy, or radiation therapy 5.
- Colonoscopy is recommended for patients with rectal thickening to rule out underlying neoplasia 6.
- In patients with severe symptoms or previous negative endoscopic examination, capsule endoscopy may be considered 4.
Correlation with Endoscopic Abnormalities
- Studies have shown that bowel wall thickening on CT scans is correlated with endoscopic abnormalities, including neoplastic and inflammatory conditions 3, 5.
- The positive predictive value of CT scans for bowel wall thickening is high, ranging from 78.1% to 87.5% 3.
- Endoscopic evaluation is recommended for patients with CT evidence of bowel wall thickening, especially in cases involving the transverse colon or in Caucasian patients with symptoms of rectal bleeding 5.