Methods, devices and systems are provided to analyze the immunologic response of patients at various times before, during and/or after immunomodulating therapy, particularly treatment with specialized pulsed electric field energy. In some embodiments, such methods, devices and systems include a laboratory developed test that utilizes a patient tumor biopsy sample and a series of blood draws to determine whether the locoregional therapy (with or without additional systemic therapies, or systemic therapies-alone) was sufficient to facilitate an increase in tumor-specific antibody production. In some embodiments, the focus is on evaluation of baseline antibody levels, prior to any treatment, and changes in levels of antibodies to given antigens, especially in response to a given therapy treatment. In such embodiments, this antibody testing is performed prior to treatment. The treatment, such as delivery of specialized PEF energy to a target tissue, is then performed and antibody levels are checked at one or more later timepoints to detect changes in the presence of antibodies and therefore response to therapy.