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 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

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

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

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*

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

PURPOSE: External beam radiotherapy (EBRT) is a useful option to treat head and neck skin cancer patients who are not indicated for surgery. In this study, we evaluated the treatment outcomes of EBRT in an Asian population.MATERIALS AND METHODS: The records from 19 head and neck skin cancer patients (10 with squamous cell carcinoma and 9 with basal cell carcinoma) who were treated with definitive or adjuvant EBRT from 2009 to 2017 were retrospectively reviewed. The radiotherapy doses administered ranged from 50 to 66 Gy (median, 55 Gy) with 2.0–2.75 Gy per daily fraction (median, 2.5 Gy). The T stage at presentation was as follows: Tis (1 patient), T1 (11 patients), T2 (6 patients), and T3 (1 patient). None had regional lymph node disease or distant metastasis at presentation. The local failure-free survival (LFFS) rates, toxicity, and cosmetic results were analyzed.RESULTS: The median age was 75.5 years (range, 52.6 to 92.5 years). The median follow-up duration from the completion of radiotherapy was 44.9 months (range, 5.8 to 82.6 months). One local failure occurred in a patient with a 2.1-cm posterior neck squamous cell carcinoma at 32.5 months after radiotherapy (1/19, 5.3%). The 3-year LFFS rate was 91.7%. No patients died from skin cancer during follow-up, and no grade 3 complications occurred. The cosmetic outcomes were excellent for 16 (84.2%) and good for 3 (15.8%) of the 19 patients.CONCLUSION: EBRT offers good local control and cosmetic outcomes in patients with head and neck skin cancer, with no grade 3 complications.
Asian Continental Ancestry Group ; Carcinoma, Squamous Cell ; Follow-Up Studies ; Head ; Humans ; Lymph Nodes ; Neck ; Neoplasm Metastasis ; Radiotherapy ; Retrospective Studies ; Skin Neoplasms ; Skin ; Treatment Outcome

Pharyngocutaneous fistula is a relatively common, but serious complication after pharyngeal or laryngeal cancer surgery. It can cause wound infection, longer hospitalization period and sometimes carotid artery rupture which can be fatal. Recently, we experienced a 63-year-old larynx cancer patient who had dementia and alcoholic liver cirrhosis for underlying diseases. He underwent total laryngectomy and both neck dissection, and pharyngocutaneous fistula occurred during postoperative radiotherapy. Pharyngocutaneous fistula during postoperative radiotherapy has not yet reported in the literature, and there are few reports about pre and postoperative management of dementia patient after head and neck cancer surgery. Therefore, we report this case with a brief review of literature.
Carotid Arteries ; Dementia ; Fistula ; Head and Neck Neoplasms ; Hospitalization ; Humans ; Laryngeal Neoplasms ; Laryngectomy ; Larynx ; Liver Cirrhosis, Alcoholic ; Middle Aged ; Neck Dissection ; Radiotherapy ; Rupture ; Wound Infection

PURPOSE: The aim is to study the dependence of deformable based auto-segmentation of head and neck organs-at-risks (OAR) on anatomy matching for a single atlas based system and generate an acceptable set of contours. METHODS: A sample of ten patients in neutral neck position and three atlas sets consisting of ten patients each in different head and neck positions were utilized to generate three scenarios representing poor, average and perfect anatomy matching respectively and auto-segmentation was carried out for each scenario. Brainstem, larynx, mandible, cervical oesophagus, oral cavity, pharyngeal muscles, parotids, spinal cord, and trachea were the structures selected for the study. Automatic and oncologist reference contours were compared using the dice similarity index (DSI), Hausdroff distance and variation in the centre of mass (COM). RESULTS: The mean DSI scores for brainstem was good irrespective of the anatomy matching scenarios. The scores for mandible, oral cavity, larynx, parotids, spinal cord, and trachea were unacceptable with poor matching but improved with enhanced bony matching whereas cervical oesophagus and pharyngeal muscles had less than acceptable scores for even perfect matching scenario. HD value and variation in COM decreased with better matching for all the structures. CONCLUSION: Improved anatomy matching resulted in better segmentation. At least a similar setup can help generate an acceptable set of automatic contours in systems employing single atlas method. Automatic contours from average matching scenario were acceptable for most structures. Importance should be given to head and neck position during atlas generation for a single atlas based system.
Brain Stem ; Head and Neck Neoplasms ; Head ; Humans ; Larynx ; Mandible ; Methods ; Mouth ; Neck ; Organs at Risk ; Pharyngeal Muscles ; Radiotherapy ; Spinal Cord ; Trachea