Background coloration of squamous epithelium in esophago-pharyngeal squamous cell carcinoma: what causes the color change?
OBJECTIVE
This study aims to clarify the cause of background coloration in the epithelia between each dilated intra papillary capillary loop in esophago-pharyngeal squamous cell carcinoma.


METHODS
This is a single center retrospective study including 124 patients with 160 lesions who underwent esophagogastroduodenoscopy in Nagasaki University Hospital from September 2007 to March 2012; a detailed comparison between endoscopic images and pathology was performed. Immunohistological assessment using anti-human hemoglobin antibody (anti-Hb Ab) was performed to verify the presence of hemoglobin (Hb) component in the cancer cells. Real-time polymerase chain reaction (RT-PCR) and in situ hybridization (ISH) on Hb-β mRNA were performed to assess the production of Hb component within the cancer cells.


RESULTS
A strong positivity for anti-Hb Ab was observed in the squamous cell carcinoma area, whereas non-cancerous mucosa showed no immunopositivity for Hb. The concordance rate between anti-Hb Ab immunoreactivity and the presence of BC was as high as 80.9%. The amount of Hb-β mRNA expression was three times higher in cancer tissues compared with the surrounding non-cancerous mucosa. ISH images showed that the expression exclusively occurred in cancer cells, indicating that Hb is probably produced within cancer cells.


CONCLUSIONS
The background coloration observed is partly due to an extravascular component of Hb. RT-PCR and ISH analyses indicate that Hb is produced within cancer cells.
Department of Gastroenterology and Hepatology, Nagasaki University Hospital, Nagasaki, Japan.
Hitomi
H
Minami
Department of Gastroenterology and Hepatology, Nagasaki University Hospital, Nagasaki, Japan.
Hajime
H
Isomoto
Department of Pathology, Nagasaki University Hospital, Nagasaki, Japan.
Toshiyuki
T
Nakayama
Department of Pathology, Nagasaki University Hospital, Nagasaki, Japan.
Tomayoshi
T
Hayashi
Department of Gastroenterology and Hepatology, Nagasaki University Hospital, Nagasaki, Japan.
Naoyuki
N
Yamaguchi
Department of Gastroenterology and Hepatology, Nagasaki University Hospital, Nagasaki, Japan.
Kayoko
K
Matsushima
Department of Gastroenterology and Hepatology, Nagasaki University Hospital, Nagasaki, Japan.
Yuko
Y
Akazawa
Department of Gastroenterology and Hepatology, Nagasaki University Hospital, Nagasaki, Japan.
Ken
K
Ohnita
Department of Gastroenterology and Hepatology, Nagasaki University Hospital, Nagasaki, Japan.
Fuminao
F
Takeshima
Digestive Disease Center, Showa University Northern Yokohama Hospital, Yokohama, Kanagawa, Japan.
Haruhiro
H
Inoue
Department of Gastroenterology and Hepatology, Nagasaki University Hospital, Nagasaki, Japan.
Kazuhiko
K
Nakao
D002294:Carcinoma, Squamous Cell / Q000378:metabolism*; D004848:Epithelium / Q000378:metabolism*; D004938:Esophageal Neoplasms / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D010610:Pharyngeal Neoplasms / Q000378:metabolism*; D010858:Pigmentation / Q000502:physiology; D012189:Retrospective Studies