lable at ScienceDirect

Clinical Oncology 22 (2010) 84–88

Contents lists avai

Clinical Oncology

journal homepage: www.elsevier .com/locate /c lon

Letters

Triple-negative Breast Cancer and Brain Metastases

Sir d We read the study by Venkitaraman et al. [1] inwhich they concluded that triple-negative breast cancersexhibit an elevated risk and an earlier occurrence of brainmetastases. They suggested several reasons for a higherpropensity for brain metastases in triple-negative breastcancer patients. We want to add another reason. A recentstudy by Bos et al. [2] looked at the genes that mediatebreast cancer metastasis to the brain. They identified thecyclooxygenase COX2, the epidermal growth factor receptor(EGFR) ligand HBEGF, and the alpha2,6-sialyltransferaseST6GALNAC5 as mediators of cancer cell passage throughthe blood–brain barrier. Furthermore, one of the pivotalstudies on basal-like breast cancer showed that EGFRexpression is one of the surrogate markers for a specificdefinition of basal-like breast cancer [3]. Therefore, thetendency for triple-negative cancer cells to metastasise tothe brain may be explained by their higher expression ofEGFR. Further studies are needed to confirm this proposal.

0936-6555/$36.00

B. Sait*, E. Cinar*, K. Altundagy*Department of Internal Medicine, Hacettepe University

School of Medicine, Ankara, TurkeyyDepartment of Medical Oncology, Hacettepe University

Institute of Oncology, Ankara, Turkey

References

[1] Venkitaraman R, Joseph T, Dhadda A, et al. Prognosis ofpatients with triple-negative breast cancer and brain metas-tasis. Clin Oncol (R Coll Radiol) 2009;21:729–730.

[2] Bos PD, Zhang XH, Nadal C, et al. Genes that mediatebreast cancer metastasis to the brain. Nature 2009;459:1005–1009.

[3] Cheang MC, Voduc D, Bajdik C, et al. Basal-like breast cancerdefined by five biomarkers has superior prognostic valuethan triple-negative phenotype. Clin Cancer Res 2008;14:1368–1376.

� 2009 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

doi:10.1016/j.clon.2009.08.010

Liver Resection of Colorectal Metastases and Adjuvant Chemotherapy:can Published Data Really Support Clinicians in Clinical Practice?

Sir d We read with great interest the recent papers ofMitry et al. [1] and Nordlinger et al. [2] related to the roleof adjuvant chemotherapy in patients with liver metas-tases from colorectal cancer treated with radical surgery(Table 1).

The correct definition of the role of adjuvant treatmentsafter surgery in radically resected patients represents one ofthe topics in gastrointestinal oncology, and the reasons forthe controversial results reported in the two papers arevarious and merit to be analysed in detail.

First, the difficulty in enrolling patients into randomisedclinical trials designed to investigate the role of adjuvantchemotherapy after radical surgery seems evident: in thepooled analysis of Mitry and coworkers [1], the investiga-tors reported the cumulative data of only 278 patients, and

in the experience of Nordlinger and coworkers [2], only364 patients were considered eligible and enrolled intothe trial. Considering that to reach a statistically signifi-cant difference of 10% (the statistically non-significantabsolute risk reduction of relapse reported with adjuvantchemotherapy), adopting an alpha and beta error of 5 and10% needs more than 950 patients. It seems evident thatno existing trial could really show any significant advan-tage for adjuvant chemotherapy as no trial was adequatelypowered to reach any outcome from a statistical point ofview [1–4].

Moreover, the clinical heterogeneity of the patientsenrolled into the single trials seems to be a further reason ofbias in the interpretation of the results. It is known that theprognostic characteristics of the patients radically resected