Risk of colorectal neoplasm in patients with acromegaly: a meta-analysis

Abstract

Aim: To examine the risk of colorectal neoplasm in acromegalic patients by meta-analyzing all relevant controlled studies.

Methods: Extensive English language medical literature searches for human studies, up to December 2007, were performed using suitable keywords. Pooled estimates [odds ratio (OR) with 95% confidence intervals (CI)] were obtained using either the fixed or random-effects model as appropriate. Heterogeneity between studies was evaluated with the Cochran Q test whereas the likelihood of publication bias was assessed by constructing funnel plots. Their symmetry was estimated by the adjusted rank correlation test.

Results: For hyperplastic polyps the pooled ORs with 95% CI were 3.557 (2.587-4.891) by fixed effects model and 3.703 (2.565-5.347) by random effects model. The Z test values for overall effect were 7.81 and 6.984, respectively (P < 0.0001). For colon adenomas the pooled ORs with 95% CI were 2.486 (1.908-3.238) (fixed effects model) and 2.537 (1.914-3.364) (random effects model). The Z test values were 6.747 and 6.472, respectively (P < 0.0001). For colon cancer the pooled OR with 95% CI was identical for both fixed and random effects model (OR, 4.351; 95% CI, 1.533-12.354; Z = 2.762, P = 0.006]. There was no significant heterogeneity and no publication bias in all the above meta-analyses.

Conclusion: Acromegaly is associated with an increased risk of colorectal neoplasm.

Figure 1

Flow diagram of the studies identified in this meta-analysis.

Figure 2

Forest plot showing individual and pooled ORs (95% CIs) and P values in studies comparing the colon adenoma prevalence in acromegaly patients and controls.

Figure 3

Funnel plot of selected studies examining colon adenoma prevalence in acromegaly patients and controls. No evidence of publication bias found (P = 0.711, by adjusted rank correlation test). Similarly no evidence of publication bias was found for the other colon neoplasias studied, i.e. colon hyperplastic polyps and colon cancer (see results, Table 2).

Figure 4

Forest plot showing individual and pooled ORs (95% CIs) and P values in studies comparing the colon hyperplastic polyp prevalence (A) and the colon cancer prevalence (B) in acromegaly patients and controls.