Colorectal cancer (CRC) is the second leading cause of cancer in Puerto Rico (PR) accounting
for approximately 1,500 individuals annually, which represent 12% of all cancer cases in the
island. The genetic epidemiology of CRC among Hispanic populations is not well studied, hence
studies focused on large, well defined ethnic groups such as Puerto Ricans, are clearly
warranted. The first step towards evaluating the molecular, environmental, and genetic
epidemiology of CRC in PR is to establish a population-based familial CRC registry. The
following specific aims have been proposed:
Specific Aim 1: To prospectively identify and recruit approximately 300 CRC probands from two
distinct geographical areas in PR (Metropolitan and Southern Region). From each proband the
investigators will obtain a pedigree extended to second-degree relatives and cousins.
Assuming 10% will be positive for a family history of CRC, the investigators will then
recruit all 30 probands with a family history of CRC and a sample of 15 family-history
negative probands and obtain: paraffin-embedded tumors blocks, blood samples, risk factor and
food frequency questionnaires.
Specific Aim 2: To prospectively identify and recruit selected relatives (parents,
grandparents, and same generation relatives - cousins and siblings) from the 45 probands
identified in Specific Aim 1. In addition, for siblings and cousins of probands (i.e.
relatives in the same generation as the proband), the investigators will obtain risk factor
and food frequency questionnaires, and for colorectal cancer cases, tumor blocks and
pathology reports of their cancers.
Specific Aim 3: To estimate from this pilot study the following parameters: (a) response rate
of probands and their selected relatives; (b) response rate of participants for each data
item; (c) family history of CRC and other cancers; (d) number of living first- and
second-degree relatives and cousins of probands; (e) number of these relatives who live in
the same household and region/municipality; (f) prevalence/distribution of selected risk
factors from the administered questionnaires.