title: Evaluation of pulmonary nodules in Asian population.
abstract: BACKGROUND
  American College of Chest Physicians (ACCP) provides guidelines to manage pulmonary nodules. Pulmonary nodules however can be malignant or benign. Similar incidence of tuberculosis (TB) and lung cancer in Asian countries raises concern over the relevance of suggested guidelines in Asian population. There is little data on the pattern of clinical practice in the management of pulmonary nodules in Asian country (Singapore). Our study describes the current pattern of clinical practice in this area highlighting the variation in practice and discussing the potential reasons.
  
  
  METHODS
  Retrospective review of the medical records of patients diagnosed with lung cancer in 2010.
  
  
  RESULTS
  Sixty nodules were identified in 32 patients. Nodules were detected incidentally on routine imaging in 7 (21.9%) patients. TB contact tracing and pre-employment screening were common ways by which nodules were detected incidentally. Over one third (37.5%) were non-smokers. Majority of nodules were located in the upper lobes of right and left lung followed by right lower lobe (RLL). Only few patients 8 (25%) had positron emission tomography (PET) scan for staging purposes. There were no difference in survival between patients who presented with single, 747 (range, 25-1,840) days vs. multiple nodules 928 (range, 30-2,572) days, P=0.26. In a retrospective analysis of malignancy risk with the probability calculator, 62.5% patients were at low-moderate risk whilst 32.5% were at high risk.
  
  
  CONCLUSIONS
  The clinical practice of managing pulmonary nodules in Asian population differs from ACCP guidelines. None of the patient had pre-test probability calculated, and few had PET scan. This is because upper lobe predominance of lung cancer is identical to TB, non-smoking history does not have any weight in discounting malignancy risk where many of the Asian lung cancer patients are non-smokers, and the local endemicity of TB and its confounding effect on radiological findings of CT scan and PET scan.
authors.affiliation: Department of Respiratory and Critical Care Medicine, Tan Tock Seng Hospital, Singapore 308433, Singapore.
authors.forename: Chee K
authors.initials: CK
authors.lastname: Phua
authors.affiliation: Department of Respiratory and Critical Care Medicine, Tan Tock Seng Hospital, Singapore 308433, Singapore.
authors.forename: Wen Y
authors.initials: WY
authors.lastname: Sim
authors.affiliation: Department of Respiratory and Critical Care Medicine, Tan Tock Seng Hospital, Singapore 308433, Singapore.
authors.forename: Kuan
authors.initials: K
authors.lastname: Sen Tee
authors.affiliation: Department of Respiratory and Critical Care Medicine, Tan Tock Seng Hospital, Singapore 308433, Singapore.
authors.forename: Sennen J W
authors.initials: SJ
authors.lastname: Lew
authors.affiliation: Department of Respiratory and Critical Care Medicine, Tan Tock Seng Hospital, Singapore 308433, Singapore.
authors.forename: Albert Y H
authors.initials: AY
authors.lastname: Lim
authors.affiliation: Department of Respiratory and Critical Care Medicine, Tan Tock Seng Hospital, Singapore 308433, Singapore.
authors.forename: Dessmon Y H
authors.initials: DY
authors.lastname: Tai
authors.affiliation: Department of Respiratory and Critical Care Medicine, Tan Tock Seng Hospital, Singapore 308433, Singapore.
authors.forename: Soon Keng
authors.initials: SK
authors.lastname: Goh
authors.affiliation: Department of Respiratory and Critical Care Medicine, Tan Tock Seng Hospital, Singapore 308433, Singapore.
authors.forename: Ai Ching
authors.initials: AC
authors.lastname: Kor
authors.affiliation: Department of Respiratory and Critical Care Medicine, Tan Tock Seng Hospital, Singapore 308433, Singapore.
authors.forename: Alan W K
authors.initials: AW
authors.lastname: Ng
authors.affiliation: Department of Respiratory and Critical Care Medicine, Tan Tock Seng Hospital, Singapore 308433, Singapore.
authors.forename: John
authors.initials: J
authors.lastname: Abisheganaden
authors.affiliation: Department of Respiratory and Critical Care Medicine, Tan Tock Seng Hospital, Singapore 308433, Singapore.
authors.forename: Akash
authors.initials: A
authors.lastname: Verma
keywords: Asia; Nodule; cancer (lung); histoplasmosis; tuberculosis (TB)