Objective: To identify in what phases in the treatment of head and neck cancer do delays happen at a tertiary hospital and to determine the association between the length of treatment delays and the oncologic outcomes (disease-free survival and overall survival) for patients with head and neck cancer. : Methods Design: Retrospective Cohort Study Setting: Tertiary National University Hospital Participants: Sixty-eight (68) patients who had surgery and adjuvant radiotherapy for invasive head and neck cancer at the Philippine General Hospital during the 5-year period of January 2014 to December 2019 were included in the initial consideration. Only 15 had survival data and were thus eligible for inclusion in this study. Results: The median treatment package time for head and neck cancers in our institution was 27.6 weeks or 193 days. The treatment package time statistically correlated with both overall survival, F(1,13)=12.952, p <0.005, R2=0.499, and disease-free survival, F(1-13)=12.823, p <0.005, R2= 0.497. However, the independent effects of other predictors such as time interval between first consult to histopathologic diagnosis, diagnosis to surgery, and surgery to post-operative radiotherapy, showed no statistically significant association with overall survival and disease free survival. Conclusion All study patients experienced treatment delays from diagnosis to surgery, and surgery to adjuvant radiation therapy, and in their total treatment package time. The positive correlation among treatment package time, and disease-free and overall survival in this study must be further investigated in order to elucidate the true effect of delays across time intervals in the treatment of head and neck cancer in the Philippine General Hospital. Every effort should be made towards timely management of these patients.
Head and Neck Neoplasms ; Radiotherapy ; Survival Rate ; Treatment Outcome ; Time-to-Treatment ; Surgery ; Disease-Free Survival ; Delayed Diagnosis ; Retrospective Studies ; Postoperative Care

OBJECTIVE: To evaluate the intra-fraction and inter-fraction positional deviations in head and neck tumor patients undergoing intensity-modulated radiation therapy (IMRT) guided by cone-beam CT (CBCT), as well as the correction capability and stability of the HexaPOD evo RT 6D couch in addressing these deviations. METHODS: From May 2019 to April 2022, 59 consecutive patients with head and neck tumors were enrolled at the Department of Radiation Oncology, Peking University Third Hospital.Using the Elekta AXESSE image-guided stereotactic treatment system, a pre-treatment CBCT scan was performed, followed by bone window mode registration with the planning reference images.Deviations were corrected automatically or manually on the 6D couch, followed by a second CBCT scan for confirmation of the deviation correction.Positional errors in translation (X, Y, Z directions) and rotation (Rx, Ry, Rz directions) were recorded before and after correction, and intra-fraction and inter-fraction positional errors were analyzed. RESULTS: Positional error data before and after correction of the 6D couch were successfully obtained and corrected online in 506 CBCT scans.The maximum positional errors before and after correction were 0.90 cm to 0.04 cm (X direction), 1.74 cm to 0.09 cm (Y direction), 1.80 cm to 0.09 cm (Z direction), and 2.90° to 0.14°(Rx direction), 3.00° to 0.15°(Ry direction), 3.00° to 0.15°(Rz direction), respectively.The mean absolute values of translational (X, Y, Z directions) and rotational (Rx, Ry, Rz directions) errors significantly decreased after online correction, from 0.18 cm, 0.22 cm, 0.25 cm, and 0.82°, 1.11°, 0.73° to 0.01 cm, 0.01 cm, 0.01 cm, and 0.04°, 0.06°, 0.04°(all P values < 0.001).After correction, the frequencies of translational errors less than 0.10 cm in the X, Y, Z directions were 99.60%, 98.62%, and 95.45%, respectively, and the frequencies of rotational errors less than 0.2° were all above 99.80%. CONCLUSION Online correction combined with CBCT and the 6D couch significantly reduces both translational and rotational positional errors in patients undergoing head and neck radiation therapy, greatly enhancing the precision of treatment.
Humans ; Cone-Beam Computed Tomography ; Head and Neck Neoplasms/diagnostic imaging* ; Radiotherapy, Image-Guided/methods* ; Radiotherapy, Intensity-Modulated/methods* ; Patient Positioning/methods* ; Radiotherapy Planning, Computer-Assisted/methods* ; Male ; Radiotherapy Setup Errors/prevention & control* ; Female

OBJECTIVE: To propose an deep learning-based algorithm for automatic prediction of dose distribution in radiotherapy planning for head and neck cancer. METHODS: We propose a novel beam dose decomposition learning (BDDL) method designed on a cascade network. The delivery matter of beam through the planning target volume (PTV) was fitted with the pre-defined beam angles, which served as an input to the convolution neural network (CNN). The output of the network was decomposed into multiple sub-fractions of dose distribution along the beam directions to carry out a complex task by performing multiple simpler sub-tasks, thus allowing the model more focused on extracting the local features. The subfractions of dose distribution map were merged into a distribution map using the proposed multi-voting mechanism. We also introduced dose distribution features of the regions-of-interest (ROIs) and boundary map as the loss function during the training phase to serve as constraining factors of the network when extracting features of the ROIs and areas of dose boundary. Public datasets of radiotherapy planning for head and neck cancer were used for obtaining the accuracy of dose distribution of the BDDL method and for implementing the ablation study of the proposed method. RESULTS: The BDDL method achieved a Dose score of 2.166 and a DVH score of 1.178 (P < 0.05), demonstrating its superior prediction accuracy to that of current state-ofthe-art (SOTA) methods. Compared with the C3D method, which was in the first place in OpenKBP-2020 Challenge, the BDDL method improved the Dose score and DVH score by 26.3% and 30%, respectively. The results of the ablation study also demonstrated the effectiveness of each key component of the BDDL method. CONCLUSION The BDDL method utilizes the prior knowledge of the delivery matter of beam and dose distribution in the ROIs to establish a dose prediction model. Compared with the existing methods, the proposed method is interpretable and reliable and can be potentially applied in clinical radiotherapy.
Humans ; Deep Learning ; Head and Neck Neoplasms/radiotherapy* ; Algorithms ; Neural Networks, Computer

Antineoplastic Agents/adverse effects* ; Head and Neck Neoplasms ; Humans ; Radiotherapy/adverse effects* ; Stomatitis/prevention & control*

Objective: To develop a designing software of digital oral positioning stent for radiotherapy of head and neck, and to compare its clinical effect with traditional oral positioning stents made by lost wax process. Methods: Thirty patients with nasopharyngeal cancer who received oral examination before radiotherapy in the prosthodontics department from July to December, 2021, were selected and divided into three groups according to the patients' wishes, 10 per group: one group without radiotherapy oral positioning stents, one group with traditional oral positioning stents (traditional stents group), and the third group with digital oral positioning stents (digital stents group). Patients' ages range from 20 years old to 71 years old. There were 15 males and 15 females involved in this study. The manufacturing time and comfort of the two positioning stents were evaluated, and the radiation doses of the radiotherapy target areas and surrounding healthy tissues were statistically analyzed at the end of radiotherapy. Results: The manufacturing time of digital stents group [(209±7) min] was much less than that of traditional stents group [(490±10) min] (t=69.85, P<0.001). The comfort of patients' wearing of digital stents [first wearing: 5 (3, 6) score; at the end of radiotherapy: 4 (3, 5) score] was better than that of traditional ones [first wearing: 7 (3, 7) score; at the end of radiotherapy: 7 (3, 7) score] (U=22.00, P=0.033; U=20.50, P=0.023). There was no significant differences in the target radiation doses among the three groups, and the radiation doses of tongue [traditional stents group: (36.74±5.45) Gy; digital stents group: (35.96±4.98) Gy] and mandible [traditional stents group: (35.46±4.19) Gy; digital stents group: (35.34±3.98) Gy] were significantly lower in the patients wearing oral positioning stents than in the patients without oral positioning stents [tongue: (41.49±4.46) Gy; madible: (39.32±3.52) Gy] (P<0.05). Conclusions: Oral positioning stents for nasopharyngeal carcinoma radiotherapy could greatly reduce the exposure doses of tongue and madible of patients. Digital oral positioning stents designed and manufactured by independently developed software had higher production efficiency than the traditional method, and patients' evaluation of comfort was better.
Humans ; Male ; Female ; Young Adult ; Adult ; Nasopharyngeal Neoplasms/radiotherapy* ; Head and Neck Neoplasms/radiotherapy* ; Tongue ; Stents ; Neck ; Radiotherapy Dosage

Oral squamous cell carcinoma (OSCC) is the most frequent tumour in head and neck malignant. The current treatment is mainly based on surgery therapy, radiation therapy and chemical therapy. Meanwhile, there are many a defect in the treatment. For example, there are many defects in radiotherapy. Radioactive salivatitis is the most common. In addition, there are a series of changes such as dry mouth, oral mucositis, rampant dental caries, and radioactive osteomyelitis of jaw, which cause swallowing, chewing problems, and taste dysfunction. Currently, the research on radioactive salivatitis is progressing rapidly, but its mechanism is more complication. This paper review aims to summarize the research progress in this field.
Carcinoma, Squamous Cell ; Dental Caries ; Head and Neck Neoplasms/radiotherapy* ; Humans ; Mouth Neoplasms ; Radiation Injuries ; Salivary Glands ; Xerostomia/etiology*

OBJECTIVES: Osteoradionecrosis (ORN) is one of the most severe complications resulting from radiotherapy (RT) in patients with head and neck cancer (HNC). It is characterized by persistent exposed and devitalized bone without proper healing for greater than 6 months after a high dose of radiation in the area. To describe the profile and dental management of ORN in HNC patients undergoing RT in an oncological clinical research center. MATERIALS AND METHODS: A retrospective descriptive study was performed to analyze dental records from HNC patients with ORN treated at an oncological clinical research center from 2013 to 2017. A total of 158 dental records for HNC patients were selected from a total of 583 records. Afterwards, this number was distributed to three examiners for manual assessments. Each examiner was responsible for selecting dental records that contained an ORN description, resulting in 20 dental records. RESULTS: Mean patient age was 60.3 years with males being the most affected sex (80.0%). The most affected area was the posterior region of the mandible (60.0%) followed by the anterior region of the mandible (20.0%) and the posterior region of the maxilla (10.0%). The factors most associated with ORN were dental conditions (70.0%) followed by isolated systemic factors (10.0%) and tumor resection (5.0%). There was total exposed bone closure in 50.0% of cases. The predominant treatment was curettage associated with chlorhexidine 0.12% irrigation (36.0%). CONCLUSION: Poor dental conditions were related to ORN occurrence. ORN management through less invasive therapies was effective for the closure of exposed bone areas and avoidance of infection.
Chlorhexidine ; Curettage ; Dental Records ; Head and Neck Neoplasms ; Head ; Humans ; Jaw ; Male ; Mandible ; Maxilla ; Osteoradionecrosis ; Radiotherapy ; Retrospective Studies

PURPOSE: An enhanced recovery after surgery (ERAS) protocol incorporates up-to-date perioperative care principles; the primary aim in using an ERAS protocol is to reduce issues that delay the recovery and cause the complications. The aim of this study was to compare outcomes associated with head and neck cancer surgery with free-flap reconstruction before and after implementation of an ERAS protocol. METHODS: Outcomes were analyzed by dividing patients into 2 groups: 29 patients in the non-ERAS group and 60 patients in the ERAS group. The ERAS group performed a prospective observational cohort study of patients who underwent a head and neck cancer surgery with free-flap reconstruction in Ajou University Hospital from August 2015 to December 2017. The non-ERAS group retrospectively reviewed the medical records of patients who had undergone the same surgery from August 2012 to July 2015. RESULTS: Demographics, comorbidities, hospital length of stay (LOS), postoperative complications, starting time of rehabilitation, and postoperative periods before radiotherapy for the non-ERAS and ERAS groups were compared. Hospital LOS was significantly lower for patients whose care followed the ERAS protocol than for patients in the non-ERAS group (30.87 ± 20.72 days vs. 59.66 ± 40.43 days, P < 0.0001). CONCLUSION: In this study, hospital LOS was reduced through fast recovery after the implementation of the ERAS protocol. Therefore, the ERAS protocol appeared feasible and safe in head and neck cancer surgery with free-flap reconstruction.
Cohort Studies ; Comorbidity ; Demography ; Free Tissue Flaps ; Head and Neck Neoplasms ; Head ; Humans ; Length of Stay ; Medical Records ; Perioperative Care ; Postoperative Care ; Postoperative Complications ; Postoperative Period ; Prospective Studies ; Radiotherapy ; Radiotherapy, Adjuvant ; Rehabilitation ; Retrospective Studies

MRI simulation images quality of head and neck coil scanning is better than that of radiotherapy surface coil, but currently the head and neck coil is not compatible with radiotherapy positioning devices. In this paper, a new fixation device is developed based on computer reverse engineering technology, which can be used in combination with head and neck coil. This article focuses on discussing the feasibility of the new device in radiotherapy. The obtained ACR phantom and Cat phantom 504 images were used to analyze MR and CT images quality assurance indicators. The dose attenuation of 6 MV photons was measured using the ionization chamber. The results showed each index met the clinical application requirements of intracranial tumor radiotherapy, thereby it can be used in intracranial tumor radiotherapy.
Feasibility Studies ; Head and Neck Neoplasms ; diagnostic imaging ; Humans ; Magnetic Resonance Imaging ; instrumentation ; Phantoms, Imaging ; Radiotherapy Planning, Computer-Assisted

OBJECTIVE: This study aimed to evaluate the risk factors of radiation-induced caries by using a multiple linear regression equation and to provide the basis for the effective prevention of radioactive caries. METHODS: A total of 166 patients with head and neck cancer who underwent radiotherapy were selected as subjects. The number of decayed, missing or filled surfaces were recorded. Questionnaire contents included age, sex, radiation dose, and radiotherapy techniques. Multiple stepwise regression analyses were performed to identify the risk factors of radiation-induced caries. RESULTS: Multiple stepwise regression analyses indicated that the main risk factors of radiation-induced caries were plaque index, radiotherapy techniques, time after radiotherapy, and radiotherapy dose. CONCLUSIONS The awareness of dental care and caries treatment should be improved to reduce the occurrence of radiation-induced caries in patients with head and neck cancer. In addition, intensity modulated radiation therapy should be employed to decrease the radiation exposure dose received by teeth.
Dental Caries ; epidemiology ; etiology ; Head and Neck Neoplasms ; radiotherapy ; Humans ; Radiation Injuries ; epidemiology ; Risk Factors ; Tooth