GALENOS 1 in Head and Neck, Lung, and Rectal Cancer Patients

Inclusion Criteria: * Written informed consent provided before study procedures * Male or female participants aged 18 years or older * Histological or cytological documentation of head and neck squamous cell carcinoma, locally advanced rectal cancer, or lung cancer * Candidate for standard antineoplastic treatment according to clinical practice * ECOG Performance Status score less than 2 * Adequate kidney, liver, and bone marrow function * Ability to adhere to study visits and protocol requirements Exclusion Criteria: * Incomplete recovery from surgery before start of antineoplastic treatment * Other additional malignancies progressing or requiring active treatment within the previous 3 years, except localized basal cell carcinoma, localized squamous cell carcinoma of the skin, or cervical carcinoma in situ * Active infection requiring systemic antibiotic therapy Serious or unstable medical conditions, psychiatric disorders, or substance abuse that would interfere with study compliance * Receipt of any live vaccine within 30 days before planned start of study therapy * Active cardiac pacing/pacing implants/neurostimulators/hearing systems not compatible with bioimpedance analysis * Edema and/or ascites interfering with body weight evaluation or bioimpedance analysis * Enteral or parenteral nutritional support at baseline