Evaluation of a 'Watch and Wait' Approach for Chemotherapy in Patients with Newly Diagnosed Advanced Non-small Cell...

Systemic therapy in advanced non-small cell lung cancer (NSCLC) is the standard of care. The time of treatment administration has not been examined in the metastatic setting. A 'watch and wait' approach for the initiation of chemotherapy is sometimes used in clinical practice, either because of patient preference, presumed indolent disease behaviour, upfront radiotherapy or other interventions. We propose to evaluate the effect of a watch and wait approach on systemic treatment deliverability and patients' outcomes in a population-based study.

A retrospective analysis of stage IIIB/IV NSCLC patients referred to medical oncology at the British Columbia Cancer Agency in 2009 was conducted. We defined the following: immediate chemotherapy (ICT) - chemotherapy ≤ 8 weeks from medical oncology consult; watch and wait chemotherapy (WWC) - initial observation with chemotherapy > 8 weeks from medical oncology consultation; watch and wait missed (WWM) - watch and wait patients who did not receive chemotherapy; best supportive care (BSC) - patients deemed chemotherapy ineligible. Statistical methods included Kaplan-Meier analysis, Log-rank tests and Cox proportional hazards modelling.

In total, 744 patients were seen by medical oncology; 355 (48%) received ICT, 173 (23%) watch and wait and 216 (29%) BSC. Of the 173 patients on a watch and wait approach, 42% missed an opportunity for chemotherapy due to poor performance status (50%), death (49%) and comorbidity (1%). The median overall survival was as follows: watch and wait 11.5 months, ICT 12.8 months and BSC 4.3 months (P < 0.0001). Controlling for confounding factors (age, gender, performance status), overall survival was longer in WWC (hazard ratio 0.73, confidence interval 0.81-1.07, P = 0.023) and lower in WWM (hazard ratio 1.68, 95% confidence interval 1.27-2.22, P < 0.0001), compared with ICT.

A significant proportion of watch and wait patients never receive systemic therapy, predominantly due to a decline in performance status. Patients in the ICT group were younger, had a better performance status and had non-squamous histology compared with the watch and wait group. The overall survival was longer in the patients who received ICT versus watch and wait. The watch and wait strategy is associated with a high risk of missing the opportunity for any chemotherapy and should be judiciously implemented only in carefully selected patients.