To the Editor The article by Pearlman et al¹ broaches a matter of high importance; 1 in 6 patients with a diagnosis of early-onset colorectal cancer (CRC) carries a germline defect in a known cancer susceptibility gene. Of these, 1 in 8 carries a CRC-predisposing allele while 3% of the individuals tested carried mutations in breast cancer genes with high or moderate penetrance. These might be simply incidental findings and although they can be clinically actionable for the individuals themselves and their families, a direct association with CRC predisposition has not been established.

中文翻译：

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早发性结直肠癌患者的突变频率

致编辑Pearlman 等人的文章¹提出了一个非常重要的问题。每 6 名诊断为早发性结直肠癌 (CRC) 的患者中就有 1 名携带已知癌症易感基因的种系缺陷。其中，八分之一的人携带易患 CRC 的等位基因，而 3% 的被测个体携带高或中等外显率的乳腺癌基因突变。这些可能只是偶然的发现，尽管它们对个人及其家人在临床上是可行的，但与 CRC 易感性的直接关联尚未确定。