Inclusion Criteria:  Suspected or confirmed diagnosis of lung cancer (non-small cell lung cancer, small-cell lung cancer or neuroendocrine tumor) for which a standard of care Transcervical Extended Mediastinal Lymphadenectomy (TEMLA) is planned Planned pre-procedural IV antibiotic. The choice of antibiotic type is up to the treatment physician(s) Able to safely hold all oral medications on the day of surgery and the day after to ensure the absorption of such drugs is not affected due to charcoal ingestion the night before surgery 18 years of age or older Able to provide written consent prior to any research related activities  Exclusion Criteria:  Current pregnancy or breastfeeding (SOC pre-TEMLA testing/assessment) Any current diagnosed disease with known involvement of the gastrointestinal tract Known allergy to oral activated charcoal CTCAE v 5 Dysphagia Grade 2 (symptomatic and altered eating/swallowing) or greater Known risk of aspiration based on history or current complaints Gastrointestinal procedures within 2 weeks before or (planned) after TEMLA Systemic antibiotic use within 8 weeks before planned TEMLA