{"doi":"10.1016/j.adro.2025.101787","title":"Different Patterns of Oral Mucositis and Microbiota Injury After Total Body Irradiation- Versus Chemotherapy-Based Myeloablative Allogeneic Hematopoietic Cell Transplantation","abstract":"Purpose: Oral mucositis (OM) is a common complication of allogeneic hematopoietic cell transplantation, causing pain, infections, swallowing/speech impairment, and poor quality of life. We hypothesized that patterns (severity and dynamics) of OM and oral microbiota disruptions may be different after high-dose total body irradiation (TBI)- versus chemotherapy-based myeloablative conditioning. Methods and Materials: We conducted an exploratory study including comprehensive, longitudinal mucositis assessment, paired with supragingival plaque and saliva collection. OM was assessed at baseline and days +7, +14, +21, +28, and +84. Total mucositis score at each timepoint was calculated from objective findings in 2 domains and 9 oral sites using a validated scoring system. Plaque and saliva samples (baseline and days +14, +28, and +84) were profiled using shotgun metagenomic sequencing. Results: A total of 249 OM assessments were performed and 342 samples were collected from 47 patients (27 chemotherapy-based, 20 TBI-based). Salivary flow rate remained stable in the chemotherapy-based cohort, but steadily declined in the TBI-based cohort, reaching a significantly lower level in the TBI-based cohort at day +84 both compared to baseline and the chemotherapy-based cohort. OM severity peaked at day +7 in the TBI-based cohort versus day +14 in the chemotherapy-based cohort. Day +14 OM was significantly more severe in the chemotherapy-based cohort; other timepoints were not different. Although the cohorts were similar in plaque microbiota composition at baseline, they became significantly different at all post- hematopoietic cell transplantation timepoints. Salivary microbiota composition was not significantly different between the 2 cohorts. Day +84 plaque microbiota diversity was significantly higher in the TBI-based cohort. Conclusions: We demonstrated different patterns of OM, microbiota injury, and salivary flow rate after TBI- versus chemotherapy-based conditioning. If validated in future studies, our findings could enhance evidence-based pretransplant counseling on oral toxicity and have implications for short- and long-term oral health in transplant survivors.","journal":"Advances in Radiation Oncology","year":2025,"id":564395,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":0,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9662,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2025-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1269409,"name":"Hakan Gem","orcid":"0000-0003-1910-7716","position":1,"is_corresponding":false},{"id":1269906,"name":"Gale Sebastian","orcid":null,"position":2,"is_corresponding":false},{"id":1269907,"name":"Rania Abasaeed","orcid":null,"position":3,"is_corresponding":false},{"id":1101806,"name":"Michele Lloid","orcid":null,"position":4,"is_corresponding":false},{"id":494363,"name":"Yolanda D. Tseng","orcid":"0000-0002-4070-346X","position":5,"is_corresponding":false},{"id":261752,"name":"Omar Y. Mian","orcid":"0000-0002-8133-8120","position":6,"is_corresponding":false},{"id":433550,"name":"Samuel S. Minot","orcid":"0000-0003-1639-3905","position":7,"is_corresponding":false},{"id":1101221,"name":"David Dean","orcid":"0000-0002-9750-6862","position":8,"is_corresponding":false},{"id":313704,"name":"Armin Rashidi","orcid":"0000-0002-9384-272X","position":9,"is_corresponding":false},{"id":1039962,"name":"Maryam Ebadi","orcid":"0009-0004-5848-4789","position":0,"is_corresponding":true}],"reference_count":12,"raw_metadata":null,"created_at":"2026-07-19T02:56:20.933088Z","pmid":"40475394","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}