Predictive factors of malignancy in adults with intussusception.

Introduction: Adult intussusception is an unusual entity, and its etiology differs from that in pediatric patients. The aim of this study was to evaluate our experience of 60 adult patients with intussusception and determine if there are any preoperative factors predictive of malignancy.
Methods: The records of 60 adult patients (>18 years of age) with a diagnosis of intussusception surgically treated at Singapore General Hospital and Changi General Hospital between 1990 and 2004 were retrospectively reviewed. The intussusceptions were classified as enteric or colonic. Preoperative predictive factors of malignancy were analyzed using univariate and multivariate analyses, and P<0.05 was considered statistically significant.
Results: There were 60 patients with a median age of 57.5 years (range 21-85 years). Altogether, 34 (56.7%) patients were male, and there were 31 enteric and 29 colonic intussusceptions. A lead point was identified in 54 patients (90%). A total of 22 (36.7%) patients presented with intestinal obstruction, and the correct preoperative diagnosis of intussusception was made in 31 patients (51.7%). Computed tomography was the most useful diagnostic modality, correctly identifying an intussusception in 24 of 30 patients. A malignant pathology was present in 8 of 31 (26%) enteric versus 20 of 29 (69%) colonic intussusceptions. Age (P=0.009), the presence of anemia (P<0.001), and the site of the intussusception (P=0.001) showed significant differences between the benign and malignant groups by univariate analyses. On multivariate analysis, intussusception in the colon (P=0.004) and the presence of anemia (P=0.001) were independent predictive factors of malignancy.
Conclusions: Adult intussusception is most commonly secondary to a pathologic lead point. The site of intussusception in the colon and the presence of anemia are independent preoperative predictors of malignancy. All colonic intussusceptions should be resected en bloc without reduction, whereas a more selective approach can be applied for enteric intussusceptions.