Purpose: It is now clinically relevant to identify and refer patients with hereditary nonpolyposis colorectal cancer (HNPCC) for genetic evaluation; family history is essential. We studied the utility of a brief personal and family history (PFH) questionnaire for identifying hereditary CRC patients in a general clinic setting.
Methods: 204 unselected CRC patients resected from 4/95 - 12/97 consented to this study. Detailed 3-generation pedigrees (PED) were obtained for research, and we abstracted physician notes and PFH information from medical records. Criteria used to identify patients for genetic referral were: 1) Patient or relative diagnosed with HNPCC-associated cancer before age 50; 2) At least two first or second-degree relatives with HNPCC-associated cancer. Patients were classified as Low risk (0 criteria), Increased risk (1 criterion), or High risk (2 criteria). Accuracy of PFH to classify patients was compared with PED ( gold standard ); sensitivity, specificity and kappa were computed.
Results: With PFH, 156 (76.5%), 41 (20.1%), and 7 (3.4%) patients were assigned as Low, Increased, and High risk, respectively. Compared to PED, 17 (8.3%) patients would have been misclassified. All true Low risk patients were idetified by PFH. Kappa scores for agreement between PFH and PED by relative category were high (.74 to 1.0).
Conclusions: Identification of kindreds at risk for HNPCC can be accurately established by obtaining a simple family history determining age of onset and occurrence of HNPCC-associated cancers in first and second degree relatives of the proband with CRC.The brief PFH instrument is almost equivalent to PED for collecting family history information. Along with two simple criteria described above, clinicians may quickly triage the CRC patients and identify those who should be considered for medical genetics evaluation, and appropriate surgical and surveillance guidelines.