A prospective study on lung toxicity in patients treated with gemcitabine and carboplatin: clinical, radiological and functional assessment

Background: Small series and retrospective studies have suggested that treatment with gemcitabine may be associated with pulmonary toxicity. However, a prospective evaluation of cancer patients treated with gemcitabine-based chemotherapy without neoplastic involvement of the thorax and without administration of radiotherapy has not been performed.

Patients and methods: To investigate this issue, 41 consecutive patients receiving gemcitabine and carboplatin underwent prospective evaluation of lung function, which included pulmonary symptoms, pulmonary function tests, arterial blood gases and radiographic studies. Assessment was performed before and after completion of chemotherapy in all patients. Patients with a substantial decline in diffusion capacity for carbon monoxide (DLCO), defined as a drop of > or = 20%, were reassessed 2 months later.

Results: After chemotherapy, there were no significant changes in forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC ratio, alveolar volume or total lung capacity. In contrast, there was a significant decline in DLCO (73 +/- 22 versus 67 +/- 24% predicted; P = 0.017) and in carbon monoxide transfer coefficient (KCO) (89 +/- 24 versus 80 +/- 24% predicted; P = 0.004). Arterial blood gases did not change following treatment. Ten of the 41 patients (24%) exhibited a substantial decline in DLCO, which, however, recovered within 2 months (DLCO at baseline, immediately after therapy and at 2 months after completion of treatment, 84 +/- 14, 58 +/- 16 and 77 +/- 17% predicted, respectively; P < 0.001; baseline DLCO versus DLCO at 2 months, P > 0.05). Four of the 41 patients (10%) experienced dyspnea, which was self-limiting, with the exception of one patient who developed interstitial lung fibrosis. Among the various risk factors examined, older age, female gender and lower baseline DLCO were associated with more profound changes in DLCO post-treatment.

Conclusions: This prospective analysis showed that the combination of gemcitabine and carboplatin induces a significant, but reversible, decrease in diffusion capacity, which is mostly asymptomatic. Thus, this regimen is safe as regards clinically significant lung toxicity.