Longitudinal analysis at three oral sites links oral microbiota to clinical outcomes in allogeneic hematopoietic stem-cell transplant.

IMPORTANCE: The oral cavity is the ultimate doorway for microbes entering the human body. We analyzed oral microbiota dynamics in allogeneic hematopoietic stem-cell transplant recipients and showed that microbiota injury and recovery patterns were highly informative on transplant complications and outcomes. Our results highlight the importance of tracking the recipient's microbiota changes during allogeneic hematopoietic stem-cell transplant to improve our understanding of its biology, safety, and efficacy.

Unusual gingival actinomycosis post allogeneic hematopoietic stem-cell transplant: case report.

BACKGROUND: Allogeneic hematopoietic stem cell transplant (allo-HSCT) is used to treat several hematological diseases, but immunosuppression during allo-HSCT facilitates opportunistic microbial growth in tissues, such as actinomycosis. An effective diagnosis of opportunistic diseases is essential for correct management of the disease and preservation of the immunosuppressed patient's life. CASE DESCRIPTION: A 57-year-old female patient was diagnosed with extranodal nasal type NK/T cell lymphoma and underwent curative treatment with allo-HSCT. Twenty-one days after the last clinical follow-up, the patient presented a necrotizing lesion in the papilla region between the first and second molars of the second quadrant. Histopathological analysis showed the presence of a bacterial cluster consistent with Actinomyces infection, and a dense lymphoid infiltrate was also observed. Immunohistochemistry for CD20, CD3, and CD56 was performed to exclude the possibility of the recurrence of extranodal NK/T cell lymphoma. Oral microbiota profiling showed a huge increase in the abundance of Actinomyces bacteria in the subgingival region three weeks prior to appearance of the lesion. CONCLUSIONS: Opportunistic infections with an unusual clinical appearance are confounding factors in therapeutic decision-making. We present for the first time a case of actinomycosis in the gingival papilla region following allo-HSCT. We also highlight how microbiota profiling through next-generation sequencing could be used to anticipate bacterial infection diagnosis.

Oral shedding of herpesviruses and clinical outcomes in hematopoietic stem cell transplant patients.

OBJECTIVES: To characterize the oral shedding of herpes viruses in patients who underwent allogeneic hematopoietic stem cell transplantation (alloHSCT) and investigate its relationship with clinical outcomes. MATERIALS AND METHODS: Polymerase chain reaction and enzymatic digestion were performed to identify the oral shedding of the members of the Herpesviridae family in 31 patients. The samples were collected from the oral cavity at five timestamps. RESULTS: The presence of each herpesvirus in the oral cavity was observed in 3.2%, 12.9%, 19.3%, 32.2%, 54.8% and 93.5% patients for human herpesvirus (HHV)-6A, herpes simplex virus-1, HHV-6B, cytomegalovirus (CMV), Epstein-Barr virus (EBV) and HHV-7, respectively. Oral shedding of herpes virus was not uncommon after alloHSCT. There was a statistically significant association between the EBV and CMV oral shedding at C1 and the cumulative incidence of acute graft-versus-host disease (aGVHD). The results suggested that the presence of HSV-1 at C2 was related to a relapse. The HHV-7 oral shedding at C2 suggests a possible link between relapse, progression-free survival and overall survival of the patients. CONCLUSIONS: Patients who developed aGVHD showed higher CMV and EBV shedding in the oral cavity at aplasia, suggesting modifications to the pattern of immune cell response and inflammatory microenvironment.

Commensal oral microbiota impacts ulcerative oral mucositis clinical course in allogeneic stem cell transplant recipients.

Oral mucositis (OM) is a complex acute cytotoxicity of antineoplastic treatment that affects 40-85% of patients undergoing hematopoietic stem-cell transplantation. OM is associated with prolonged hospitalization, increased extensive pharmacotherapy, need for parenteral nutrition, and elevated treatment costs. As OM onset relates to the mucosal microenvironment status, with a particular role for microbiota-driven inflammation, we aimed to investigate whether the oral mucosa microbiota was associated with the clinical course of OM in patients undergoing allogeneic hematopoietic stem-cell transplantation. We collected oral mucosa samples from 30 patients and analyzed the oral mucosa microbiota by 16S rRNA sequencing. A total of 13 patients (43%) developed ulcerative OM. We observed that specific taxa were associated with oral mucositis grade and time to oral mucositis healing. Porphyromonas relative abundance at preconditioning was positively correlated with ulcerative OM grade (Spearman ρ = 0.61, P = 0.028) and higher Lactobacillus relative abundance at ulcerative OM onset was associated with shortened ulcerative OM duration (P = 0.032). Additionally, we generated a machine-learning-based bacterial signature that uses pre-treatment microbial profiles to predict whether a patient will develop OM during treatment. Our findings suggest that further research should focus on host-microbiome interactions to better prevent and treat OM.

Oral mucositis in paediatric cancer patients undergoing allogeneic hematopoietic stem cell transplantation preventively treated with professional dental care and photobiomodulation: Incidence and risk factors.

BACKGROUND: Oral mucositis (OM) is an important side effect related to allogeneic hematopoietic stem cell transplantation (allo-HSCT), and it has been associated with a significative reduction of quality of life. A negative impact of OM in paediatric patients could result in increased use of parenteral feeding and opioids, longer periods of hospitalization, and a higher risk of systemic infection. AIM: To investigate the clinical features and clinical outcomes associated with OM development and severity in hematological cancer paediatric patients undergoing allo-HSCT who underwent professional dental care (PDC) and photobiomodulation (PBM) as prophylactic treatment. DESIGN: Medical data and OM presentation were retrieved retrospectively from all patients younger than 18 years who received allo-HSCT between 2013 and 2016. The incidence of OM was assessed and graded by two oral medicine specialists following the WHO guidelines, and it was correlated with clinical parameters. RESULTS: Forty-nine consecutive paediatric patients were included. OM was diagnosed in 73.5% of patients, and in 36.1% of patients, OM was classified as severe. Acute lymphoblastic leukemia as a primary diagnosis and the use of a myeloablative regimen were associated with OM development. The primary diagnosis and use of total body irradiation (TBI) were associated with aggressive OM. Neither the incidence nor the severity of OM affected the overall survival, whereas only the use of a myeloablative regimen and a high body mass index (BMI) were determinants of lower OM-free survival rates. CONCLUSIONS: A myeloablative conditioning and a high BMI were observed to be independent prognostic determinants of a lower OMFS rate. The cluster analysis allowed us to outline patient profiles with greater susceptibility to the development and severity of oral mucositis, which seems to be a useful tool to determine the risk of OM in paediatric patients.

Disruption of the oral microbiota is associated with a higher risk of relapse after allogeneic hematopoietic stem cell transplantation.

Intestinal microbiota (IM) diversity and composition regulates host immunity and affects outcomes after allogeneic stem cell transplantation (allo-HSCT). We evaluated if the oral mucosa microbiota (OM) could impact the outcomes in patients who underwent allo-HSCT. Samples from the oral mucosa of 30 patients were collected at three time points: before the conditioning regimen, at aplasia, and at engraftment. We analyzed the associations of OM diversity and composition with allo-HSCT outcomes. Lower OM diversity at preconditioning was associated with a higher risk of relapse at 3 years (68% versus 33%, respectively; P = 0.04). Dominance (relative abundance ≥ 30%) by a single genus at preconditioning was also associated with a higher risk of relapse (63% versus 36% at 3 years, respectively; P = 0.04), as well as worse progression-free survival (PFS; 19% versus 55%, respectively; P = 0.01), and overall survival (OS) at 3 years (38% versus 81%, respectively; P = 0.02). In our study we observed that OM dysbiosis is associated with a higher risk of relapse and worse survival after allo-HSCT.

Dental Biofilm Microbiota Dysbiosis Is Associated With the Risk of Acute Graft-Versus-Host Disease After Allogeneic Hematopoietic Stem Cell Transplantation.

Acute graft-versus-host disease (aGVHD) is one of the major causes of death after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Recently, aGVHD onset was linked to intestinal microbiota (IM) dysbiosis. However, other bacterial-rich gastrointestinal sites, such as the mouth, which hosts several distinctive microbiotas, may also impact the risk of GVHD. The dental biofilm microbiota (DBM) is highly diverse and, like the IM, interacts with host cells and modulates immune homeostasis. We characterized changes in the DBM of patients during allo-HSCT and evaluated whether the DBM could be associated with the risk of aGVHD. DBM dysbiosis during allo-HSCT was marked by a gradual loss of bacterial diversity and changes in DBM genera composition, with commensal genera reductions and potentially pathogenic bacteria overgrowths. High Streptococcus and high Corynebacterium relative abundance at preconditioning were associated with a higher risk of aGVHD (67% vs. 33%; HR = 2.89, P = 0.04 and 73% vs. 37%; HR = 2.74, P = 0.04, respectively), while high Veillonella relative abundance was associated with a lower risk of aGVHD (27% vs. 73%; HR = 0.24, P < 0.01). Enterococcus faecalis bloom during allo-HSCT was observed in 17% of allo-HSCT recipients and was associated with a higher risk of aGVHD (100% vs. 40%; HR = 4.07, P < 0.001) and severe aGVHD (60% vs. 12%; HR = 6.82, P = 0.01). To the best of our knowledge, this is the first study demonstrating that DBM dysbiosis is associated with the aGVHD risk after allo-HSCT.

Late recurrence of Burkitt's lymphoma in the jaw: numb chin syndrome as the only symptom.

The Numb Chin Syndrome (NCS) is defined as facial and oral numbness restricted to the mental nerve's distribution involving the lower lip, skin of the chin, or gingiva of the lower anterior teeth. Hypoesthesia can occur unilaterally or bilaterally. Although this syndrome is rare, its importance is related to the fact that it represents the clinical manifestations of malignant diseases. Breast cancer and non-Hodgkin lymphoma are the most common cause of NCS. The patient, a 58-year-old woman, treated for a Burkitt Lymphoma (BL) nine years ago, described a two-week history of change in sensitivity and pain in the chin region, without relief with the use of analgesics. She had no headache, speech disturbance, dysphagia, visual disturbance, or other neurological symptoms. No surgical intervention has been performed recently. The intraoral examination revealed a healthy oral mucosa and a small area adjacent to the right mental nerve region that was uncomfortable to palpation. No changes were found in the bone trabeculae at cone-beam computed tomography. The contrasted magnetic resonance features made it possible to identify a change in the mandibular body extending to the entire right side, coinciding with the patient's complaint, indicating a probable mandibular medullary invasion. The patient was submitted to a biopsy to rule out a possible recurrence of BL. The microscopic findings were consistent with the diagnosis of BL. The present report described a very unusual presentation of late recurrent BL nine years after the first treatment, which manifested as an NCS.

MASCC/ISOO clinical practice guidelines for the management of mucositis: sub-analysis of current interventions for the management of oral mucositis in pediatric cancer patients.

OBJECTIVE: The aim of this sub-analysis was to highlight the MASCC/ISOO clinical practice guidelines for the management of oral mucositis (OM) in pediatric patients and to present unique considerations in this patient population. METHODS: This sub-analysis of the pediatric patient population is based on the systematic review conducted by the Multinational Association of Supportive Care in Cancer/International Society of Oral Oncology (MASCC/ISSO) published in 2019/2020. Studies were scored and assigned a level of evidence based on previously published criteria. Data regarding adverse effects and compliance was collected from the original publications. RESULTS: A total of 45 papers were included and assessed in this sub-analysis, including 21 randomized controlled trials (RCTs). Chewing gum was demonstrated to be not effective in preventing OM in pediatric cancer patients in 2 RCTs. The efficacy of all other interventions could not be determined based on the available literature. CONCLUSION: There is limited or conflicting evidence about interventions for the management of OM in pediatric cancer patients, except for chewing gum which was ineffective for prevention. Therefore, currently, data from adult studies may need to be extrapolated for the management of pediatric patients. Honey and photobiomodulation therapy in this patient population had encouraging potential. Implementation of a basic oral care protocol is advised amid lack of high level of evidence studies.

Late recurrence of Burkitt's lymphoma in the jaw: numb chin syndrome as the only symptom

The Numb Chin Syndrome (NCS) is defined as facial and oral numbness restricted to the mental nerve's distribution involving the lower lip, skin of the chin, or gingiva of the lower anterior teeth. Hypoesthesia can occur unilaterally or bilaterally. Although this syndrome is rare, its importance is related to the fact that it represents the clinical manifestations of malignant diseases. Breast cancer and non-Hodgkin lymphoma are the most common cause of NCS. The patient, a 58-year-old woman, treated for a Burkitt Lymphoma (BL) nine years ago, described a two-week history of change in sensitivity and pain in the chin region, without relief with the use of analgesics. She had no headache, speech disturbance, dysphagia, visual disturbance, or other neurological symptoms. No surgical intervention has been performed recently. The intraoral examination revealed a healthy oral mucosa and a small area adjacent to the right mental nerve region that was uncomfortable to palpation. No changes were found in the bone trabeculae at cone-beam computed tomography. The contrasted magnetic resonance features made it possible to identify a change in the mandibular body extending to the entire right side, coinciding with the patient's complaint, indicating a probable mandibular medullary invasion. The patient was submitted to a biopsy to rule out a possible recurrence of BL. The microscopic findings were consistent with the diagnosis of BL. The present report described a very unusual presentation of late recurrent BL nine years after the first treatment, which manifested as an NCS.

Myeloid sarcoma in the tongue.

Leukemic cells are rarely present in the oral cavity, and there are very few reports regarding such cases. However, we identified some reports of leukemic cells infiltrating tissues in the oral cavity, including gingival involvement. Recurrent painful oral ulcerations and prominent generalized periodontal destruction are the most common oral features of neutrophil disorders, and they may even be the initial symptoms of the disease. The ulcers may affect any part of the oral mucosa, including the tongue and palate. The objective of this report is to describe and discuss a case of myeloid sarcoma in the oral cavity of a 48-year-old male patient.

Undifferentiated pleomorphic sarcoma of the mandible.

Undifferentiated pleomorphic sarcoma (UPS) is a high-grade neoplasm that is usually located in the extremities and retroperitoneum. In the past, UPS was considered the most common soft tissue sarcoma in adults; due to improvements in diagnostic techniques, most cases have been reclassified as other lineage-specific tumors. Gnathic bones are rarely affected, and the clinicopathological characteristics of this neoplasm when diagnosed in the jaw remain to be better described. In this report, we present a rare case of mandibular UPS affecting an 88-year-old female who demonstrated a painful swelling on the right side of the mandible that was accompanied by a pathological fracture. Microscopic examination revealed a pleomorphic spindlecell neoplasm with mitotic figures and necrosis. The patient underwent surgery and adjuvant radiotherapy but experienced metastasis after 12 months of follow-up and died. Diagnosis of UPS is challenging, and oral pathologists must be aware of this entity when dealing with aggressive undifferentiated neoplasms.

Myeloid sarcoma in the tongue

Leukemic cells are rarely present in the oral cavity, and there are very few reports regarding such cases. However, we identified some reports of leukemic cells infiltrating tissues in the oral cavity, including gingival involvement. Recurrent painful oral ulcerations and prominent generalized periodontal destruction are the most common oral features of neutrophil disorders, and they may even be the initial symptoms of the disease. The ulcers may affect any part of the oral mucosa, including the tongue and palate. The objective of this report is to describe and discuss a case of myeloid sarcoma in the oral cavity of a 48-year-old male patient.

Current knowledge regarding medication-related osteonecrosis of the jaw among different health professionals.

PURPOSE: To assess the current knowledge regarding medication-related osteonecrosis of the jaw (MRONJ); the adverse effects of anti-resorptive (AR) and anti-angiogenic (AA) drugs; strategies for MRONJ prevention and treatment; and perception of the dentist's role in assisting patients who use these drugs among physicians, dentists, and nurses. METHODS: Using questionnaires, the current knowledge of MRONJ was assessed among dentists, physicians, and nurses, who were divided into group I, which included specialties that directly assist cancer patients, and group II, which included other specialties. The questionnaires assessed the characteristics of the health professionals, training time, and specialties; their knowledge of AR and AA drugs; and their knowledge of MRONJ. RESULTS: A total of 1370 health professionals participated in the study, including 1032 dentists, 239 physicians, and 99 nurses. Among dentists and physicians, the training time (p = 0.036 and p < 0.001, respectively) and specialization in group I domains (p < 0.001 and p < 0.001, respectively) had a significant impact on MRONJ knowledge, while nurses showed no significant impact regardless of the training time and specialty. Less than 10% of the physicians and dentists could correlate the signs and symptoms of all stages of MRONJ. CONCLUSION: The findings indicated a notable lack of knowledge regarding MRONJ among dental surgeons and physicians, and especially among nurses. More experienced professionals and specialists in the areas that assist cancer patients usually have a greater understanding of the dentist's role in MRONJ prevention, diagnosis, treatment, and patient care and will introduce or are already using AR and AA drugs.

Digital Workflow for Producing Oral Positioning Radiotherapy Stents for Head and Neck Cancer.

Oral positioning radiotherapy stents are devices that protect healthy structures adjacent to the target volume of head and neck radiotherapy treatment, leading to reduced acute and chronic side effects. This study describes a digital workflow to produce an oral positioning radiotherapy stent and analyze its efficacy by measuring dosimetric variations with and without this stent. An oral positioning radiotherapy stent was created according to a digital workflow that included intraoral scanning, digital design, and 3D printing for a patient with squamous cell carcinoma of the tongue. The patient underwent computed tomography to evaluate radiotherapy treatment by intensity-modulated radiation therapy with and without the use of the 3D-printed oral stent. The use of a 3D-printed oral positioning radiotherapy stent is a feasible and reproducible technique that reduced the planning target volume and radiation doses delivered to the hard palate, right parotid gland, and left parotid gland by 42%, 21%, and 8.5%, respectively.

Herpesviruses in the oral cavity of patients subjected to allogeneic hematopoietic stem cell transplantation and its relationship with oral mucositis.

OBJECTIVES: This study was performed to characterise oral shedding of herpesviruses in patients who underwent allogeneic hematopoietic stem cell transplantation (alloHSCT) and to investigate its relationship with oral mucositis (OM). MATERIALS AND METHODS: PCR and enzymatic digestion were conducted to identify oral shedding of herpesviruses and its correlation with OM development in 31 patients. The samples were collected at three sites in the oral cavity and at 5 times during follow-up; two additional collections were made from patients who developed ulcerative OM. RESULTS: HSV-1, EBV, CMV, HHV-6A, HHV-6B, and HHV-7 were detected in 4.97%, 16.02%, 4.41%, 2.20%, 3.31%, and 68% of the oral mucosal samples, respectively; 4.41%, 16.57%, 5.52%, 2.20%, 5.52%, and 63.53% of supragingival samples, respectively, and 4.41%, 18.23%, 2.76%, 1.65%, 2.75%, and 35.91% of subgingival samples, respectively. OM was diagnosed in 13 patients. The presence of HHV-7 in C1 (oral mucosa: p = 0.032) and C2 (supragingival: p = 0.009; subgingival: p = 0.002) was significantly increased in patients who developed OM, and patients exhibiting HHV-7 shedding in the oral cavity were 3.32-fold more likely to develop OM. CONCLUSIONS: Patients who developed OM showed higher HHV-7 shedding in the oral cavity at nadir (immediately prior to OM development), suggesting modifications to the inflammatory microenvironment. CLINICAL RELEVANCE: HHV-7 may be involved in oral dysbiosis in HSCT-related OM; enhanced understanding of its role in the pathogenesis of OM may lead to the development of strategies for managing and preventing this common side effect of alloHSCT.