Prognostic significance of G1 cell-cycle inhibitors in early laryngeal cancer.
BACKGROUND
Radiation therapy yields a 2-year local control rate of 80% to 90% in early laryngeal squamous cell carcinoma. However, a subset of early laryngeal cancers has a significantly higher rate of local recurrence and lower rate of overall survival.


OBJECTIVE
The objective of this study was determine the prognostic significance of p53, p27, and p21 expression in patients with early laryngeal cancer.


METHODS
Expression of p53, p27, and p21 proteins in pretreatment biopsies from sixty-eight patients was analyzed by using immunohistochemistry. Low (</=10% cells) and high (>10% cells) levels of expression were measured. All patients were newly diagnosed and treated with external beam radiation. Other contributing factors were also studied, such as age, sex, race, tumor site, and stage.


RESULTS
Forty (58.8%) and 28 (41.2%) lesions were staged as T1 and T2, respectively, whereas 16 (23.5%) and 52 (76.5%) were located in the supraglottis and glottis, respectively. Overexpression of p27, p53, and p21 was found in 36.7%, 60.6%, and 60% of cases, respectively. Overexpression of p27 was found to be a significant predictor of recurrence by multivariate analysis (RR 3.3, P = .017). Overexpression of p21 and/or p53 was not predictive of recurrence. No factor predicted disease specific or nonspecific overall survival.


CONCLUSIONS
Our results indicate the significance of p27 overexpression as an indicator of recurrence in patients with early laryngeal squamous cell carcinoma.
Korkmaz
Hakan
H
Department of Otolaryngology-Head and Neck Surgery, Wayne State University, Detroit, MI 48201, USA.
Du
Wei
W
Yoo
George H
GH
Enamorado
Ileana I
II
Lin
Ho-Sheng
HS
Adsay
Volkan
V
Kewson
Danny
D
Ensley
John F
JF
Shibuya
Terry Y
TY
Jacobs
John R
JR
Kim
Harold
H
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000473:pathology / Q000532:radiotherapy; D018797:Cell Cycle Proteins / Q000378:metabolism*; D056746:Cyclin G; D056766:Cyclin G1; D050759:Cyclin-Dependent Kinase Inhibitor p21; D050760:Cyclin-Dependent Kinase Inhibitor p27; D016213:Cyclins / Q000378:metabolism*; D005260:Female; D005931:Glottis / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D007822:Laryngeal Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000532:radiotherapy; D007830:Larynx / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D012008:Recurrence; D012189:Retrospective Studies; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D025521:Tumor Suppressor Proteins / Q000378:metabolism
C534702:CCNG1 protein, human; C493956:CDKN1A protein, human; D018797:Cell Cycle Proteins; D056746:Cyclin G; D056766:Cyclin G1; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D016159:Tumor Suppressor Protein p53; D025521:Tumor Suppressor Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27