Serologic Response to Pneumococcal Vaccination Among Esophageal Cancer Patients With High Grade Lymphopenia After Chemoradiation

Inclusion Criteria: 1. Group 1A a. Patients currently receiving, planning to receive, or recently completed chemoradiation for esophageal cancer with protons. 2. Group 1B a. Patients currently receiving, planning to receive, or recently completed chemoradiation for esophageal cancer with intensity-modulated radiation therapy (IMRT) 3. Group 2A a. Patients currently receiving, planning to receive, or recently completed definitive proton therapy for unresectable hepatocellular carcinoma. 4. Group 2B a. Patients currently receiving, planning to receive, or recently completed definitive IMRT for unresectable hepatocellular carcinoma. 5. Group 3 a. Healthy age- and gender- matched individuals 6. All Groups 1. Patients of all genders, races and nationalities will be solicited. 2. Age \>18 years 3. Ability to understand and the willingness to sign a written informed consent document. Exclusion Criteria: * Patients with compromised immunologic responses due to an uncontrolled intercurrent immunodeficiency (e.g., Human immunodeficiency virus (HIV), X-linked agammaglobulinemia) or previous or current immune suppressive therapy a. Human immunodeficiency virus (HIV)-infected patients on effective anti-retroviral therapy with undetectable viral load within 6 months are eligible for this trial. * Patients receiving intravenous immunoglobulin (IVIG) during the study or in the three months prior to study enrollment. * Patients with psychiatric illness/social situations that would limit compliance with study requirements. * Individuals with previous pneumococcal vaccination in the last 5 years. * Individuals with severe allergy to any of the vaccine components