Skin Disorders and Primary Tumor Location as Prognostic Factors in Patients with Metastatic Colorectal Cancer Treated with Cetuximab and Chemotherapy

Abstract

Background: Cetuximab-induced skin disorder is common in colorectal cancer (CRC), and is known to affect<br />prolonged overall survival (OS). Patients with left-sided CRC survive longer than those with right-sided CRC, among<br />those treated with combination cetuximab and chemotherapy. However, no study has evaluated patient prognosis<br />in terms of OS and progression-free survival (PFS) in relation to both tumor location and skin disorder. This study<br />aimed to determine the incidence of skin disorder according to tumor location and analyze the relationship of tumor<br />location and skin disorder with OS. Methods: Patients with metastatic colorectal cancer (mCRC) treated with standard<br />chemotherapy and cetuximab as first-line therapy were included. Differences in the incidence of skin disorders due to<br />the location of the primary tumors were compared in the same patient. The OS and PFS in relation to the location of<br />the primary tumors and presence or absence of skin disorder were also compared. Results: Total frequency of each<br />skin disorder as rash acneiform, paronychia, and dry skin in patients with left- and right-sided mCRC was 70%, 70%,<br />and 43% and 27%, 36%, and 27%, respectively. The median OS was 8.9 months for mCRC on the left-sided without<br />skin disorder and 56.3 months for mCRC on the left-sided with skin disorder. In comparison, the median OS was 10.4<br />months for mCRC on the right-sided without skin disorder and 11.3 months for mCRC on the right-sided with skin<br />disease (left-sided with skin disorder versus other three group; P<0.001). Conclusions: Primary tumor location and<br />the presence of skin disorder are important factors in patients with mCRC who receive cetuximab. In particular, our<br />results show the new fact that the left-sided and right-sided mCRC survival time were comparable if there is no skin<br />disorder caused by cetuximab.