Microbiome in Lung Cancer and Other Malignancies

Inclusion Criteria: Patients diagnosed with lung cancer and other malignancies who are candidates for systemic therapies such as immunotherapy and chemotherapy Eligibility criteria for studying microbiome in patients receiving immunotherapy: * Patients with advanced/recurrent lung cancer (including both NSCLC and SCLC) and other solid tumors of our study interest (e.g. GU cancer and melanoma, etc.) that initiate a new line of immunotherapy (can be 1st or later line), either alone or in combination with chemotherapy, targeted therapy or other immunotherapy. * Patients can be in other clinical trials as long as they meet criteria 1. * Prior treatment with immunotherapy is acceptable as long as criteria 1 is met. For example, a new line therapy with pembrolizumab plus pemetrexed after failing pembrolizumab is considered eligible. * Patients who are to start immunotherapy maintenance after chemoradiation therapy are eligible (e.g. NSCLC patients who will be on durvalumab maintenance) * Patients who are to start immunotherapy after local therapies (e.g. radiation, ablation, etc.) are eligible. * Immunotherapy must have component of anti-PD-1/PD-L1 agents (e.g. nivolumab, pembrolizumab, atezolizumab, durvalumab and avelumab, etc.) or anti-CTLA4 (e.g. ipilimumab) Exclusion Criteria: * Patients \< 18 years of age * Patients that are pregnant * Patients taking more than 2 alcoholic drinks per day and those using non-medical drugs such as marijuana, cocaine, heroine, etc.