title: Lung cancer patients who are asymptomatic at diagnosis show favorable prognosis: a korean Lung Cancer Registry Study.
abstract: OBJECTIVE
  The outcomes of lung cancer patients who were asymptomatic at diagnosis have never been reported as part of a large-scale study. A national survey of lung cancer in South Korea registered a total of 8788 patients diagnosed in 2005. We report the results herein, with an emphasis on the prognosis of the asymptomatic lung cancer patients.
  
  
  RESULTS
  Adenocarcinoma was the most frequent (36.1%) histopathologic type, followed by squamous cell carcinoma (32.1%), large cell carcinoma (1.5%), and small cell carcinoma (13.5%). In most cases, lung cancer was detected with subjective symptoms, but 6.5% of cases had no symptoms indicative of lung cancer at the time of diagnosis. Compared to symptomatic patients, asymptomatic patients were younger, more often female, non-smokers, and more frequently presented with adenocarcinoma. Initial treatments were surgery (22.1%), radiation therapy (7.8%), chemo-radiation therapy (5.4%), and chemotherapy (38%), while 26.6% of patients were recorded to have supportive care only. Asymptomatic patients received surgery in 60.0% of cases, and they showed significantly longer survival times than symptomatic patients. Absence of symptoms at diagnosis significantly reduced the risk of death from non-small cell lung cancer, regardless of patient age, patient gender, stage at diagnosis, smoking history, or whether treatment was performed, but did not reduce the risk of death from small cell lung cancer.
  
  
  CONCLUSIONS
  Adenocarcinoma has grown to be the leading histopathologic type of lung cancer in South Korea. Absence of symptom at diagnosis is a favorable prognostic factor for patients with non-small cell lung cancer.
authors.affiliation: The Survey Committee of Korean Association for the Study of Lung Cancer, South Korea.
authors.forename: Kwang-Ho
authors.initials: KH
authors.lastname: In
authors.forename: Yong-Soo
authors.initials: YS
authors.lastname: Kwon
authors.forename: In-Jae
authors.initials: IJ
authors.lastname: Oh
authors.forename: Kyu-Sik
authors.initials: KS
authors.lastname: Kim
authors.forename: Maan-Hong
authors.initials: MH
authors.lastname: Jung
authors.forename: Kwan-Ho
authors.initials: KH
authors.lastname: Lee
authors.forename: Sun-Young
authors.initials: SY
authors.lastname: Kim
authors.forename: Jeong-Seon
authors.initials: JS
authors.lastname: Ryu
authors.forename: Sung-Yong
authors.initials: SY
authors.lastname: Lee
authors.forename: Eun-Taik
authors.initials: ET
authors.lastname: Jeong
authors.forename: Sang-Yeub
authors.initials: SY
authors.lastname: Lee
authors.forename: Ho-Kee
authors.initials: HK
authors.lastname: Yum
authors.forename: Chang-Geol
authors.initials: CG
authors.lastname: Lee
authors.forename: Woo-Sung
authors.initials: WS
authors.lastname: Kim
authors.forename: Jae-Ill
authors.initials: JI
authors.lastname: Zo
authors.forename: Hojoong
authors.initials: H
authors.lastname: Kim
authors.forename: Young-Whan
authors.initials: YW
authors.lastname: Kim
authors.forename: Se-Kyu
authors.initials: SK
authors.lastname: Kim
authors.forename: Jae-Cheol
authors.initials: JC
authors.lastname: Lee
authors.forename: Young-Chul
authors.initials: YC
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007723:Korea; D008175:Lung Neoplasms / Q000401:mortality* / Q000473:pathology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012042:Registries; D012307:Risk Factors; D016896:Treatment Outcome