Am. J. Respir. Crit. Care Med., Vol 153, No. 1, 01 1996, 243-249.
Lung cancer chemotherapy. Response-survival relationship depends on the method of chest tumor response evaluation
JL Pujol, E Parrat, M Lehmann, V Gautier, JP Daures, FB Michel and P Godard
Service des Maladies Respiratoires, Centre Hospitalier Regional et Universitaire de Montpellier-Nimes, France.
In a previous study we found that tumor responses as assessed by CT scan
and fiberoptic bronchoscopy are sometimes discordant. We hypothesize that
the response-survival relationship might vary according to the method of
tumor response assessment. In a multivariate analysis of survival using the
landmark method, we evaluated the prognostic significance of tumor response
assessed by CT scan or fiberoptic bronchoscopy together with bronchial
tumor location and histology of bronchial biopsies at restaging. A total of
133 lung cancer patients (50 small cell lung cancers and 83 non-small cell
lung cancers) were entered in controlled chemotherapy trials and
prospectively evaluated for chest tumor response by CT scan and fiberoptic
bronchoscopy (FOB). Only 106 patients were fully evaluable for response by
both methods. For these patients, a statistical concordance was observed
between the two tests (kappa = 0.271; p < 0.001). There was a
significant correlation between response and survival whatever the test
used. However, only CT scan evaluation resulted in a classification showing
that the more unfavorable the response stage was, the worse the survival
became with no intersection between survival curves. Cox's hazard model
demonstrated that CT- evaluated progression, proximal bronchial location at
second FOB (intermediate, main bronchus or trachea) and positive histologic
status at restaging were all prognostic determinants of poor survival. In
conclusion, CT-evaluated response led to the best response-survival
relationship as this method classified patients into four groups with
different outcomes. Fiberoptic bronchoscopy should be avoided in patients
who were found to have no endobronchial lesion during the pretreatment
staging. For patients with pretreatment assessable endobronchial lesions,
the decision of a second FOB depends on the results of CT restaging: FOB is
probably unnecessary in patients for whom progression is disclosed by CT
scan. In patients for whom CT scan discloses tumor response or
stabilization, bronchial tumor location and histology of bronchial biopsies
at second FOB are independent prognostic factors.
