title: Effect of the chest wall on the measurement of hemoglobin concentrations by near-infrared time-resolved spectroscopy in normal breast and cancer.
abstract: BACKGROUND
  Optical imaging and spectroscopy using near-infrared light have great potential in the assessment of tumor vasculature. We previously measured hemoglobin concentrations in breast cancer using a near-infrared time-resolved spectroscopy system. The purpose of the present study was to evaluate the effect of the chest wall on the measurement of hemoglobin concentrations in normal breast tissue and cancer.
  
  
  METHODS
  We measured total hemoglobin (tHb) concentration in both cancer and contralateral normal breast using a near-infrared time-resolved spectroscopy system in 24 female patients with breast cancer. Patients were divided into two groups based on menopausal state. The skin-to-chest wall distance was determined using ultrasound images obtained with an ultrasound probe attached to the spectroscopy probe.
  
  
  RESULTS
  The apparent tHb concentration of normal breast increased when the skin-to-chest wall distance was less than 20 mm. The tHb concentration in pre-menopausal patients was higher than that in post-menopausal patients. Although the concentration of tHb in cancer tissue was statistically higher than that in normal breast, the contralateral normal breast showed higher tHb concentration than cancer in 9 of 46 datasets. When the curves of tHb concentrations as a function of the skin-to-chest wall distance in normal breast were applied for pre- and post-menopausal patients separately, all the cancer lesions plotted above the curves.
  
  
  CONCLUSIONS
  The skin-to-chest wall distance affected the measurement of tHb concentration of breast tissue by near-infrared time-resolved spectroscopy. The tHb concentration of breast cancer tissue was more precisely evaluated by considering the skin-to-chest wall distance.
authors.affiliation: Department of Diagnostic Radiology and Nuclear Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashiku, Hamamatsu, Shizuoka, 431-3192, Japan. nonchan@hama-med.ac.jp.
authors.forename: Nobuko
authors.initials: N
authors.lastname: Yoshizawa
authors.affiliation: Central Research Laboratory, Hamamatsu Photonics K.K., 5000 Hirakuchi, Hamakitaku, Hamamatsu, Shizuoka, 434-8601, Japan.
authors.forename: Yukio
authors.initials: Y
authors.lastname: Ueda
authors.affiliation: Department of Diagnostic Radiology and Nuclear Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashiku, Hamamatsu, Shizuoka, 431-3192, Japan.
authors.forename: Hatsuko
authors.initials: H
authors.lastname: Nasu
authors.affiliation: Department of Breast Surgery, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashiku, Hamamatsu, Shizuoka, 431-3192, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ogura
authors.affiliation: Central Research Laboratory, Hamamatsu Photonics K.K., 5000 Hirakuchi, Hamakitaku, Hamamatsu, Shizuoka, 434-8601, Japan.
authors.forename: Etsuko
authors.initials: E
authors.lastname: Ohmae
authors.affiliation: Central Research Laboratory, Hamamatsu Photonics K.K., 5000 Hirakuchi, Hamakitaku, Hamamatsu, Shizuoka, 434-8601, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Yoshimoto
authors.affiliation: Department of Radiology, Hamamatsu University Hospital, 1-20-1 Handayama, Higashiku, Hamamatsu, Shizuoka, 431-3192, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Takehara
authors.affiliation: Central Research Laboratory, Hamamatsu Photonics K.K., 5000 Hirakuchi, Hamakitaku, Hamamatsu, Shizuoka, 434-8601, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Yamashita
authors.affiliation: Department of Diagnostic Radiology and Nuclear Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashiku, Hamamatsu, Shizuoka, 431-3192, Japan.
authors.forename: Harumi
authors.initials: H
authors.lastname: Sakahara
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000097:blood* / Q000000981:diagnostic imaging*; D005260:Female; D006454:Hemoglobins / Q000032:analysis*; D006801:Humans; D042361:Mammary Glands, Human / Q000098:blood supply; D008875:Middle Aged; D017698:Postmenopause; D017697:Premenopause; D012016:Reference Values; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D035441:Thoracic Wall / Q000033:anatomy & histology / Q000000981:diagnostic imaging
chemical_list: D006454:Hemoglobins
keywords: Breast cancer; Hemoglobin; Near-infrared time-resolved spectroscopy