Plasma Cell Disorders

This is a prospective, single-center, single-arm Phase I study evaluating GPRC5D-targeted PET/CT imaging in patients with plasma cell disorders, including multiple myeloma. Participants will undergo GPRC5D-targeted PET/CT, 18F-FDG PET/CT, and 68Ga-BCMA PET/CT within 5 days whenever feasible for head-to-head comparison of lesion detection and disease assessment. The study aims to evaluate the safety, feasibility, biodistribution, and diagnostic performance of GPRC5D-targeted PET/CT and to compare its imaging characteristics with currently available molecular imaging modalities in plasma cell disorders.

The purpose of this study is to identify multiple myeloma in the precancerous MGUS stage in order to reduce the risk of delayed diagnosis of multiple myeloma, decrease morbidity related to multiple myeloma at progression, and improve long term outcomes.

A Study to Evaluate Gut Microbiome with POEMS Syndrome and Other Plasma Cell Disorders

This is a prospective, single-arm, single-center clinical trial designed to evaluate the safety and efficacy of radiation combined with a BCMA/CD3 bispecific antibody (CM336) in patients with solitary bone plasmacytoma (SBP) with mild bone marrow infiltration.

The goal of this observational study is to register patients with plasma cell disorders. The main questions it aims to answer are: * The incidence of plasma cell disorders both before and after malignancy * Time to progression of monoclonal gammopathy of undetermined significant (MGUS) or smoldering multiple myeloma (SMM) to light chain amyloidosis or multiple myeloma (MM) * Progression free survival (PFS) * overall survival * factors influencing overall survival, progression-free survival, and time to progression * Symptoms and signs of the disease during the diagnosis and relapse phases, including the causes of mortality in plasma cell disorder patients. * genetic characteristics of plasma cell disorder * cost-effectiveness of treatment in Thailand Participants will be collected the data of baseline diagnosis, treatment, treatment results of all admission and follow-up visits from hospital medical record.