RE: Primary Tumor Location as a Prognostic Factor in Metastatic Colorectal Cancer
JNCI J Natl Cancer Inst (
correspondence RE: Primary Tumor Location as a Prognostic Factor in Metastatic Colorectal Cancer
He Wen-zhuo 0 1 2 3 4 5
Xia Liang-ping 0 1 2 3 4 5
0 2. Frattini M , Balestra D, Suardi S, et al. Different genetic features associated
1 1. Loupakis F , Yang D, Yau L, et al. Primary tumor location as a prognostic
2 Affiliation of authors: VIP Region, Sun Yat-sen University Cancer Center , Guangzhou, Guangdong, 510060 , P. R. China, HWz, XLp
3 5. Venderbosch S, de Wilt JH, Teerenstra S, et al. Prognostic value of resection
4 4. Lee YC, Lee YL, Chuang JP, et al. Differences in survival between colon
5 3. Yamauchi M, Morikawa T, Kuchiba A, et al. Assessment of colorectal cancer
Colorectal cancer is a group of distinct diseases rather than a
the impact of primary tumor location on patients who accepted
homogeneous one. Fotios Loupakis et al. ( 1) published an
interchemotherapy, as well as patients who accepted chemotherapy
esting paper, which suggested that patients with left-sided colo
plus bevacizumab. However, what they did not evaluate was the
rectal cancers had more favorable prognosis than right side.
impact of bevacizumab on survival among patients grouped
What’s more, the authors also proposed that the efficacy of
by the primary tumor location. We would like to suggest the
bevacizumab was independent of tumor location. The study was
authors compare survival between patients who accepted
based on well-known clinical trials and described in reasonable
chemotherapy alone and chemotherapy plus bevacizumab in
detail. In our opinion, there are three points that might weaken
patients with right-side colon cancer, as well as left-side colon
the stringency of their study.
First, in Fotios Loupakis’ study (1), left-side cancers were
defined as those of origin from descending colon, sigmoid colon,
or rectum. However, descending and sigmoid colon cancers
are different from rectal cancer in molecular features, trea-t
ment approaches, and prognosis ( 2–4). As a result, it may not be
appropriate to mix left-side colon and rectum into one group.
Second, although the number of metastatic sites was balanced
between groups, some other important prognostic factors were
unbalanced or unmentioned, including staging at diagnosis,
carcinoembryonic antigen levels, number of patients who accepted
R0 resection, and primary tumor resection 5( ). Last but not
least, the author mentioned that the efficacy of bevacizumab
was independent of tumor location, which in our opinion is an
overambitious conclusion. In other words, the authors studied
cancer and rectal cancer.
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