Low grade dysplasia (LGD) is believed to predispose patients to colorectal cancer (CRC). Proctocolectomy is advocated when LGD is identified.
A cohort of 160 patients with longstanding extensive ulcerative colitis (UC) underwent annual colonoscopic surveillance, between 1978 and 1990. Of these, 40 developed LGD sometime during this time.
In this study, physicians from England, report the outcome of the cohort 10 years later.
The team performed a retrospective cohort study and conducted a histopathological review of the original diagnoses of LGD.
|High grade dysplasia or colorectal cancer developed in 10% of patients.|
They found that at the end of 1990, 128 patients were alive with an intact colon. Of these, 2 were untraceable, 29 had LGD, and 97 had no dysplasia (controls).
They were able to establish the outcome of 99% patients in 2000.
The researchers determined that after 10 years, high grade dysplasia or CRC developed in 10% of the patients with LGD and in 4% of the controls.
However, when analyzed using the Kaplan-Meier method, the team found that there was not a statistically significant difference between the 2 groups.
Histopathological review also demonstrated the unreliability of LGD diagnosis.
Dr Lim's team concluded, "LGD diagnosis is not sufficiently reliable to justify prophylactic colectomy".
"Conservative management of established LGD cases should not be ruled out".