Palliative chemotherapy for metastatic lung cancer is now standard. Platinum-based combinations were the first regimens to convincingly have an impact on survival and have been the standard of care in NSCLC. A European study showed that gemcitabine/cisplatin was essentiall equivalent to paclitaxel and a platin and the former became standard in Europe whereas the latter is most often used in the USA.
NCCN does not list Gemzar for second-line therapy(NSCL-16). I did find a recent guideline that focuses specifically on the role of gemcitabine: Use of Gemcitabine in Non-Small Cell Lung Cancer
Practice Guideline Report # 7-8 (Version 2.2002) by Ellis P, Mackay JA, Evans WK, and the Lung Cancer Disease Site Group. It says: “There is currently no evidence from randomized clinical trials that second-line chemotherapy with gemcitabine is associated with any improvement in survival. The routine use of gemcitabine as second-line chemotherapy cannot be recommended. Therefore, Gemzar alone is not supported by credible scientific evidence published in peer-reviewed medical literature generally and recognized by the relevant medical community. NCCN recommends for second line: docetaxel, premetrexed or erlotinib.
nccn.org, nonsmall cell lung cancer,
Use of Gemcitabine in Non-Small Cell Lung Cancer
Practice Guideline Report # 7-8 (Version 2.2002) by Ellis P, Mackay JA, Evans WK, and the Lung Cancer Disease Site Group.