Prevalence of digital clubbing in bronchogenic carcinoma by a new digital index

Clin Exp Rheumatol. Jan-Feb 1998;16(1):21-6.


Objective: Clubbing can be a paraneoplastic manifestation of bronchogenic carcinoma. We assessed a new digital index of clubbing and used it to determine the prevalence of clubbing for different cell types of lung cancer.

Methods: Clubbing was assessed by measurement of the thickness of both the base of the nailbed (distal phalangeal depth--DPD) and the distal interphalangeal depth (IPD) of the index finger in a control group compared to patient groups with either chronic obstructive lung disease, or lung cancer.

Results: Of the 55 normal subjects, no patient had a DPD/IPD ratio of more than 1.05 on either hand, while 11% of the patients with COPD had a ratio of more than one. For the cancer patients, 33% had a ratio greater than one, with 30 of 109 (37%) having a ratio > 1.05 (chi(2) = 17.6, p < 0.0001). There was no difference in the prevalence of clubbing between the 33 squamous cell patients, the 43 adenocarcinoma patients, and the 33 small cell lung carcinoma patients included.

Conclusions: Measurement of the interphalangeal and distal phalangeal distance demonstrated that one-third of patients with lung cancer had evidence of clubbing. The type of bronchogenic carcinoma did not appear to affect the proportion of patients with clubbing.

MeSH terms

  • Adenocarcinoma / complications
  • Adenocarcinoma / epidemiology
  • Carcinoma, Bronchogenic / complications*
  • Carcinoma, Bronchogenic / epidemiology
  • Carcinoma, Small Cell / complications
  • Carcinoma, Small Cell / epidemiology
  • Carcinoma, Squamous Cell / complications
  • Carcinoma, Squamous Cell / epidemiology
  • Humans
  • Lung Diseases, Obstructive / complications
  • Lung Neoplasms / complications*
  • Lung Neoplasms / epidemiology
  • Osteoarthropathy, Secondary Hypertrophic / epidemiology*
  • Osteoarthropathy, Secondary Hypertrophic / etiology*
  • Physical Examination / standards
  • Predictive Value of Tests
  • Prevalence
  • Reproducibility of Results