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Plastic and Reconstructive Surgery.... Jun 2024Midfacial reconstruction for extensive defects of the hard nasal structures and bilateral maxillae is challenging. Postoperative radiotherapy causes skin contracture,...
Midfacial reconstruction for extensive defects of the hard nasal structures and bilateral maxillae is challenging. Postoperative radiotherapy causes skin contracture, making secondary reconstruction extremely difficult. A 57-year-old man underwent resection of the nasal bone, nasal cartilage, and hard palate for cancer of the nasal cavity. Postoperative radiotherapy (70 Gy) resulted in bilateral osteoradionecrosis. Severe depression deformity of the midface causes a disorder in closing the mouth, resulting in difficulty in conversation and oral intake. We performed simultaneous reconstruction of the bilateral maxillary and nasal hard structures using double free flaps (fibular osteocutaneous and anterolateral thigh flaps). A 16-cm right fibular osteocutaneous flap was elevated, and an 8-cm proximal bone was resected to obtain the length of the peroneal vessels. The distal 8 cm was cut into three pieces while maintaining the blood flow. The removed nonvascularized fibula was processed into two pieces of cortex: nasal bridge and columella. All areas of the skin island were de-epithelialized to bilaterally fill the maxillary sinuses. Next, the ipsilateral anterolateral thigh flap was elevated with the central 6-cm part for closure of the palate and the proximal area to fill the nasal cavity. The distal area consisted of a fascial flap to cover the reconstructed nasal structure. The chimeric double flap allowed for oral intake, conversation, and nasomaxillary prominence. Computed tomography performed 8 months postoperatively showed maintained bony structures. We used the extra fibula as a nonvascularized cortex piece to prevent infection and exposure, which enabled simultaneous reconstruction of the bilateral maxillae and hard nasal structure.
PubMed: 38919515
DOI: 10.1097/GOX.0000000000005936 -
International Journal of Radiation... Mar 2024Given the limitations of extant models for normal tissue complication probability estimation for osteoradionecrosis (ORN) of the mandible, the purpose of this study was...
Cluster-Based Toxicity Estimation of Osteoradionecrosis Via Unsupervised Machine Learning: Moving Beyond Single Dose-Parameter Normal Tissue Complication Probability by Using Whole Dose-Volume Histograms for Cohort Risk Stratification.
PURPOSE
Given the limitations of extant models for normal tissue complication probability estimation for osteoradionecrosis (ORN) of the mandible, the purpose of this study was to enrich statistical inference by exploiting structural properties of data and provide a clinically reliable model for ORN risk evaluation through an unsupervised-learning analysis that incorporates the whole radiation dose distribution on the mandible.
METHODS AND MATERIALS
The analysis was conducted on retrospective data of 1259 patients with head and neck cancer treated at The University of Texas MD Anderson Cancer Center between 2005 and 2015. During a minimum 12-month posttherapy follow-up period, 173 patients in this cohort (13.7%) developed ORN (grades I to IV). The (structural) clusters of mandibular dose-volume histograms (DVHs) for these patients were identified using the K-means clustering method. A soft-margin support vector machine was used to determine the cluster borders and partition the dose-volume space. The risk of ORN for each dose-volume region was calculated based on incidence rates and other clinical risk factors.
RESULTS
The K-means clustering method identified 6 clusters among the DVHs. Based on the first 5 clusters, the dose-volume space was partitioned by the soft-margin support vector machine into distinct regions with different risk indices. The sixth cluster entirely overlapped with the others; the region of this cluster was determined by its envelopes. For each region, the ORN incidence rate per preradiation dental extraction status (a statistically significant, nondose related risk factor for ORN) was reported as the corresponding risk index.
CONCLUSIONS
This study presents an unsupervised-learning analysis of a large-scale data set to evaluate the risk of mandibular ORN among patients with head and neck cancer. The results provide a visual risk-assessment tool for ORN (based on the whole DVH and preradiation dental extraction status) as well as a range of constraints for dose optimization under different risk levels.
PubMed: 38462018
DOI: 10.1016/j.ijrobp.2024.02.021 -
Clinical and Translational Radiation... Jan 2024PARP-inhibitors have potent radiosensitizing properties in pre-clinical models. To identify the maximum tolerated dose (MTD) of the PARP-inhibitor Olaparib in...
PURPOSE
PARP-inhibitors have potent radiosensitizing properties in pre-clinical models. To identify the maximum tolerated dose (MTD) of the PARP-inhibitor Olaparib in combination with radiotherapy in patients with head and neck cancer, a single institutional phase-I dose escalation trial was initiated.
PATIENTS AND METHODS
The starting dose of Olaparib was 25 mg BID, combined with radiotherapy (70 Gy in 35 fractions). The MTD was defined as the highest dose-level at which not more than 20 % of patients experience dose-limiting toxicities (DLT) or as the highest reached dose in the absence of DLT's.
RESULTS
One week Olaparib-only treatment (25 mg QD) was administered to all patients prior to the start of radiotherapy. In dose-level I, Olaparib (25 mg BID) was combined with accelerated radiotherapy (70 Gy in 6 weeks). Because of DLT's in 3 of the 4 treated patients (acute tracheotomy 5 and 7 months and osteoradionecrosis 7 months after treatment), the Olaparib dose was de-escalated to 25 mg QD, and combined with conventional radiotherapy (70 Gy in 7 weeks) (dose-level II). There were no DLT's observed in 5 patients treated within dose-level II. After a median follow-up of 60 months, the 4-year LRC and OS rates were 77.8 % and 88.9 %, respectively.
CONCLUSION
Olaparib 25 mg QD combined with conventionally fractionated radiotherapy was well tolerated and identified as the MTD while severe DLT's were observed when Olaparib 25 mg BID was combined with accelerated radiation. This combination might be further explored in future Olaparib dose escalation studies in patients with locally-advanced HNSCC unfit for cisplatin-based chemoradiotherapy.
PubMed: 38021094
DOI: 10.1016/j.ctro.2023.100698 -
Indian Journal of Pathology &... 2024Extranodal Natural Killer/T Cell Lymphoma Nasal Type (EN-NK/T-CL-NT) is a non-Hodgkin extranodal lymphoma of unfavorable prognosis due to its aggressive nature. This...
Extranodal Natural Killer/T Cell Lymphoma Nasal Type (EN-NK/T-CL-NT) is a non-Hodgkin extranodal lymphoma of unfavorable prognosis due to its aggressive nature. This neoplasm mainly affects the paranasal sinuses, nasopharynx, oropharynx, oral cavity, palate, and rarely intestinal, gastric and skin regions. 50-year-old female with a history of lymphoma in nasal and pelvic region. At four years of tumors-free, has facial asymmetry, accompanied by sub-palpebral, nasal and lip edema. Intraoral examination revealed a large ulceration suggestive of osteoradionecrosis. Gum biopsy shows Extranodal NK/T Cell Lymphoma Nasal Type (EN-NK/T-CL-NT). In this case we highlight the characteristics of EN-NK/T-CL-NT with a presentation of osteoradionecrosis-like. Unfortunately, the nature of this tumor led to the patient's death. Clinical follow-up of patients with cancer is imperative to mend and/or decrease treatment complications, as well as to identify second primary tumors or the spread of the underlying disease.
Topics: Female; Humans; Middle Aged; Osteoradionecrosis; Lymphoma, Extranodal NK-T-Cell; Prognosis; Pelvis; Killer Cells, Natural
PubMed: 38358211
DOI: 10.4103/ijpm.ijpm_296_22 -
Asian Pacific Journal of Cancer... Feb 2024
Topics: Humans; Prospective Studies; Chemoradiotherapy; Carcinoma; Oropharynx
PubMed: 38415519
DOI: 10.31557/APJCP.2024.25.2.367