Non-Small Cell Lung Cancer (NSCLC) is the leading cause of cancer related mortality in US (1). About 22% of patients diagnosed with NSCLC have locally advanced or stage III disease at the time of diagnosis (2). 5 years survival for stage III lung cancer is 23% which is much less than survival in similar stage breast and Colon Cancers (2). Current standard of care for inoperable stage III NSCLC is concurrent chemo-radiotherapy as established by a study (Southwestern Oncology Group) SWOG 9019 (3). Surgery following concurrent chemo-radiotherapy has been evaluated in a large Phase III clinical trial in patients with Stage III (N2) disease which did not show any improvement in overall survival from surgery as compared to concurrent chemo-radiotherapy alone.(4). These two studies demonstrated that the most common site of cancer relapse in patients with stage III disease was distant metastasis, 65% (3) and 57% (4) respectively.~These observations have led to the idea that perhaps giving additional chemotherapy following definitive concurrent chemo-radiotherapy may prevent distant relapse in stage III NSCLC.~This idea was evaluated in a Phase II study SWOG S9504 in which patients with stage III NSCLC were treated with concurrent chemo-radiotherapy followed by 4 cycles of docetaxel consolidation (5). Four cycles of docetaxel consolidation showed an impressive improvement in median Overall Survival (OS) to 26 months.~This idea of docetaxel consolidation was subsequently evaluated in a large phase III trial in which patients inoperable stage III NSCLC after receiving concurrent chemo-radiotherapy were randomized to docetaxel consolidation versus observation (6). However, this study showed no improvement in OS between the docetaxel arm and the observation arm. Many patients in docetaxel arm developed pneumonitis and febrile neutropenia.~Histology based selection of chemotherapy is now standard of for stage IV metastatic NSCLC. A large randomized Phase III trial from Europe showed that a combination of Cisplatin and Pemetrexed is more effective in patients with non-squamous histology and a combination of Cisplatin and Gemcitabine showed efficacy in patients with squamous cell histology (7). Recently maintenance Pemetrexed was evaluated in advanced NSCLC and showed improvement in PFS and OS in patients with non-squamous histology (8). Similarly maintenance gemcitabine has also been evaluated in large Phase III clinical trial after initial chemotherapy with Cisplatin and Gemcitabine (9).~Since most patients with inoperable stage III NSCLC develop distant metastasis following definitive concurrent chemo-radiotherapy there clearly is a need to give addition treatment for these patients. Docetaxel consolidation has not been shown to be successful as noted above. Perhaps tailoring chemotherapy according to histology may result in improvement in PFS and OS in these patients.~Based on this hypothesis the investigators intend to do a pilot phase II study of histology based consolidation chemotherapy in patients with inoperable stage III NSCLC following concurrent chemo-radiotherapy. Patients with inoperable stage III NSCLC would be treated with standard concurrent chemo-radiotherapy and subsequently those with non-squamous histology would be offered 4 cycles of consolidation pemetrexed and those with squamous histology 4 cycles of consolidation with gemcitabine.
This is a pilot phase II study of histology based consolidation chemotherapy in patients with inoperable stage III Non-Small Cell Lung Cancer (NSCLC) following concurrent chemo-radiotherapy. Patients with inoperable stage III NSCLC would be treated with standard concurrent chemo-radiotherapy and subsequently those with non-squamous histology would be offered 4 cycles of consolidation pemetrexed and those with squamous histology 4 cycles of consolidation with gemcitabine.