Comment on: Red Cell Distribution Width Really Acted Prognostic Role in Upper Tract Urothelial Carcinoma?

See original letter here.


By Yen-Chen Cheng,1 Ching-Chia Li,2 Wen-Jeng Wu,2 and Hsin-Chih Yeh 2

From the Kaohsiung Medical University,1 and Kaohsiung Municipal Ta-Tung Hospital,2 Kaohsiung, Taiwan

To the Editors:

We appreciate the comments by Dr. Zeng on our published article.1 First, patients with high red cell distribution width (RDW) had significantly lower body mass index than those with low RDW (22.96±3.64 versus 24.31±3.74, P = 0.015) in our derivation cohort. However, some previous studies indicated obesity was associated high RDW.2 Second, patients with obstructive jaundice or severe coagulopathy were poor surgical candidates and therefore not included in the study. Third, in our article, renal function has already been considered as a confounding factor and analyzed in the form of estimated glomerular filtration rate. Although diabetes mellitus was described to be associated with high RDW, opposite results were reported in Taiwanese population.3 To our limited knowledge, no strong evidence suggested high RDW is correlated with hypertension in multivariate analysis. No patient received antibiotics within 2 weeks before surgery since those had active infection were excluded. Lastly, we used automated counter device (Sysmex NX-9000) for RDW assessment.

As mentioned in our article, many clinical conditions and factors may influence RDW level, and RDW could be a surrogate of them. We also assumed this was the reason why elevated RDW was more closely related to overall survival than cancer-specific survival. RDW is highly applicable in the clinical setting due to its easy accessibility, and we believe RDW plays an important role in prognostic prediction for patients with upper tract urothelial carcinoma.

References

1. Cheng YC, Huang CN, Wu WJ, et al. The Prognostic Significance of Inflammation-Associated Blood Cell Markers in Patients with Upper Tract Urothelial Carcinoma. Ann Surg Oncol. 2016;23:343-51.

2. Fujita B, Strodthoff D, Fritzenwanger M, et al. Altered red blood cell distribution width in overweight adolescents and its association with markers of inflammation. Pediatr Obes. 2013;8:385-91.

3. Chen PC, Sung FC, Chien KL, Hsu HC, Su TC, Lee YT. Red blood cell distribution width and risk of cardiovascular events and mortality in a community cohort in Taiwan. Am J Epidemiol. 15 2010;171:214-20.