Can Early Dental Extractions Reduce Delays in Postoperative Radiation for Patients With Advanced Oral Cavity Carcinoma?

PURPOSE: This study sought to evaluate the effect of early extractions on the timing of postoperative radiation (PORT) for patients with advanced oral cavity squamous cell carcinoma. MATERIALS AND METHODS: All patients with oral cavity squamous cell carcinoma who required resection, free flap reconstruction, and dental extractions in a 10-year period were retrospectively reviewed. The study included patients who preoperatively had advanced disease that indicated the need for adjuvant radiation as defined by an advanced clinical T category (T3 or T4a) or clinical N category (N2a or above). Multivariate logistic regression models were created to estimate the risk factors for initiation of PORT greater than 6 weeks after surgery. RESULTS: Thirty-four patients were included. Thirteen patients underwent early extractions (before or at the time of surgery). Twenty-one patients underwent extractions after surgery. Extractions included all teeth with periodontal disease within the expected field of radiation. Most patients underwent full-mouth extractions (91.1%). PORT was initiated at greater than 6 weeks in 30.8% of patients in the early cohort, whereas 72.4% of patients in the late group experienced a delay (P = .02). Early extractions were significantly associated with a decreased risk of PORT delay. No increase in operating room time occurred for patients who underwent same-day extractions. CONCLUSIONS: Early involvement of the dental oncology department and oral-maxillofacial surgeons can aid in the timely delivery of care for patients with advanced oral cavity cancer.

Head and neck cancers, Version 2.2014. Clinical practice guidelines in oncology.

This selection from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Head and Neck Cancers focuses on glottic laryngeal cancer, which is the most common type of laryngeal cancer and has an excellent cure rate. The lymphatic drainage of the glottis is sparse, and early stage primaries rarely spread to regional nodes. Because hoarseness is an early symptom, most glottic laryngeal cancer is early stage at diagnosis. Updates to these guidelines for 2014 include revisions to "Principles of Radiation Therapy" for each site and "Principles of Surgery," and the addition of a new section on "Principles of Dental Evaluation and Management."

Assessing the knowledge and awareness of US oncologists regarding the specialty of oral medicine.

OBJECTIVES: This cross-sectional study aimed to assess the awareness among United States (US) oncologists about oral medicine (OM) as a specialty of dentistry, and their collaboration with OM providers. METHODS: An online survey was conducted, inviting 1350 US oncologists, with data collected on demographics, practice background, comfort level with diagnosing and treating oral conditions, referral practices for oral conditions, and more. RESULTS: Of the invited 1350 oncologists, 192 responded (14% response rate). Among respondents, 46% were familiar with the OM specialty. Of these, 73% had previously sought consultation from OM specialists. The primary reasons for referral included dental clearance before initiating chemotherapy (38.5%), dental clearance before initiating radiotherapy (37%), and managing oral ulcers and oral potentially malignant disorders equally (32.2%). Regarding referrals to providers outside of OM, oncologists primarily referred patients with oral lesions to otolaryngologists (64.6%), followed by oral and maxillofacial surgeons (55.2%) and general dentists (45.3%). CONCLUSION: Our study showed that over half of US oncologists were unfamiliar with the OM specialty. However, the referral rate to OM providers was high among oncologists who had prior OM knowledge. It is advisable to enhance the collaboration between OM and oncology specialists to ensure optimal care for patients with cancer.

Feasibility of accelerated image-guided high-dose-rate interstitial brachytherapy with inverse planning simulated annealing (IPSA-HDRBT) for post-operative treatment of pathologically node-negative squamous cell carcinomas of the oral tongue.

PURPOSE: Inverse planning simulated annealing (IPSA) produces highly conformal dose distributions and quick optimizations for high-dose-rate interstitial brachytherapy (HDRBT). We report our dosimetry and overall outcomes using this approach for the accelerated post-operative treatment of pathologically node-negative squamous cell carcinomas of the oral tongue (OTSCC) with high risk of local recurrence. METHODS: Patients with newly diagnosed pN0 OTSCC treated with partial glossectomy, neck dissection, and post-operative HDRBT alone from 2007 to 2021 were retrospectively reviewed. Patients received 30 Gy in 5 fractions over 2.5 days. Target volume and mandible dosimetry are reported. Actuarial rates of local control, regional control, disease-specific survival, and overall survival were estimated using the Kaplan-Meier method. Toxicity was categorized using the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. RESULTS: 19 consecutive patients were reviewed. Median follow-up was 3.2 years (IQR 1.4-8.2 years) with a 3-year estimated local control rate of 81%. Target volumes were generally small, as the median volume was 12.66 cc. Median V150% and V200% were 52% and 24%, respectively. D1cc and D2cc to the mandible were 17.31 Gy and 14.42 Gy, respectively. CONCLUSIONS: IPSA-HDRBT is feasible and highly efficient for post-operative treatment of the primary tumor bed in patients with pathologically node-negative squamous cell carcinomas of the oral tongue. Further technical optimization and prospective clinical evaluation in a larger patient cohort are planned.

Artificial Intelligence-Guided Prediction of Dental Doses Before Planning of Radiation Therapy for Oropharyngeal Cancer: Technical Development and Initial Feasibility of Implementation.

Purpose: The aim was to develop a novel artificial intelligence (AI)-guided clinical decision support system, to predict radiation doses to subsites of the mandible using diagnostic computed tomography scans acquired before any planning of head and neck radiation therapy (RT). Methods and Materials: A dose classifier was trained using RT plans from 86 patients with oropharyngeal cancer; the test set consisted of an additional 20 plans. The classifier was trained to predict whether mandible subsites would receive a mean dose >50 Gy. The AI predictions were prospectively evaluated and compared with those of a specialist head and neck radiation oncologist for 9 patients. Positive predictive value (PPV), negative predictive value (NPV), Pearson correlation coefficient, and Lin concordance correlation coefficient were calculated to compare the AI predictions to those of the physician. Results: In the test data set, the AI predictions had a PPV of 0.95 and NPV of 0.88. For 9 patients evaluated prospectively, there was a strong correlation between the predictions of the AI algorithm and physician (P = .72, P < .001). Comparing the AI algorithm versus the physician, the PPVs were 0.82 versus 0.25, and the NPVs were 0.94 versus 1.0, respectively. Concordance between physician estimates and final planned doses was 0.62; this was 0.71 between AI-based estimates and final planned doses. Conclusion: AI-guided decision support increased precision and accuracy of pre-RT dental dose estimates.

Treatment modality impact on quality of life for human papillomavirus-associated oropharynx cancer.

OBJECTIVES/HYPOTHESIS: Compare treatment-related quality of life (QOL) impact for early-stage human papillomavirus-associated oropharynx squamous cell carcinoma (HPV+ OPSCC) patients. STUDY DESIGN: Retrospective cohort at a tertiary center. METHODS: Stage I (T0-2/N0-1) HPV+ OPSCC patients (n = 76) with pretreatment Karnofsky scores ≥80 reported QOL after surgery alone (n = 17, 22%), surgery with adjuvant radiation ± chemotherapy (S-a[C]XRT) (n = 23, 30%), or definitive radiation ± chemotherapy (d[C]XRT) (n = 36, 47%) with the University of Washington QOL version 4 (UW-QOL); European Organization for Research and Treatment of Cancer Quality of Life Questionnaire, Core Module (EORTC QLQ-C30) and Head and Neck Module (EORTC QLQ-HN35); University of Michigan Xerostomia, and Neck Dissection Impairment Index questionnaires (median follow-up = 2.2 years, interquartile range = 1.0-4.2 years). Treatment adverse events and gastrostomy tube rates were assessed. RESULTS: Over 87% of each treatment group reported good or better overall QOL. Each group had low gastrostomy tube and treatment-specific complication rates. S-a(C)XRT and d(C)XRT patients had similar mean scores with wide ranges for most individual and all composite categories. S-a(C)XRT compared to d(C)XRT patients reported significantly fewer dental problems (EORTC QLQ-C30/HN35 means = 10.1 vs. 34.3, P = .007), worse appearance (UW-QOL means = 72.8 vs. 82.6, P = .02), and worse coughing (EORTC QLQ-C30/HN35 means = 31.9 vs. 15.7, P = .007). Surgery alone compared to d(C)XRT and S-a(C)XRT patients reported significantly better salivary/taste/oral functions and less pain, financial, oral/dental, and sexual problems. CONCLUSIONS: For early-stage HPV+ OPSCC, patients usually achieve acceptable QOL regardless of treatment. S-a(C)XRT and d(C)XRT patients report generally similar QOL including neck/shoulder pain/function, but with a wide range in a limited patient sample. Surgery alone should be considered, when oncologically and functionally safe, given the better associated QOL. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:E48-E56, 2020.

Perineural Invasion and Perineural Tumor Spread in Head and Neck Cancer.

Perineural invasion (PNI), the neoplastic invasion of nerves, is a common pathologic finding in head and neck cancer that is associated with poor clinical outcomes. PNI is a histologic finding of tumor cell infiltration and is distinct from perineural tumor spread (PNTS), which is macroscopic tumor involvement along a nerve extending from the primary tumor that is by definition more advanced, being radiologically or clinically apparent. Despite widespread acknowledgment of the prognostic significance of PNI and PNTS, the mechanisms underlying its pathogenesis remain largely unknown, and specific therapies targeting nerve invasion are lacking. The use of radiation therapy for PNI and PNTS can improve local control and reduce devastating failures at the skull base. However, the optimal volumes to be delineated with respect to targeting cranial nerve pathways are not well defined, and radiation can carry risks of major toxicity secondary to the location of adjacent critical structures. Here we examine the pathogenesis of these phenomena, analyze the role of radiation in PNI and PNTS, and propose guidelines for radiation treatment design based on the best available evidence and the authors' collective experience to advance understanding and therapy of this ominous cancer phenotype.

Controversies in Postoperative Irradiation of Oropharyngeal Cancer After Transoral Surgery.

Transoral surgery (TOS) is a novel technology whose adoption is expanding in the United States and other countries. TOS offers the possibility of a minimally invasive surgical approach to head and neck cancers. Its most frequent application has been in oropharyngeal cancers (OPC), of which most are associated with human papillomavirus (HPV). For HPV-associated OPC, where high response and survival rates are expected, deintensification of standard therapy is a major area of clinical research. In HPV-OPC, traditional pathologic risk factors indicating a need for adjuvant radiation or chemoradiation may not apply as strongly.

Improved outcomes in adjuvant radiotherapy for oral cavity carcinoma at an academic center: a matched-pair analysis.

OBJECTIVES/HYPOTHESIS: Our objective was to evaluate for outcomes differences for patients with oral cavity squamous cell carcinoma (OCSCC) who underwent primary surgical resection at an academic center (AC), followed by postoperative radiation therapy either at the AC or at a nonacademic radiation treatment center (non-AC). DESIGN: Secondary analysis of a retrospective cohort of patients with previously untreated upper aerodigestive tract SCC who underwent surgery followed by adjuvant therapy at an AC from 2002 to 2012. Fifty-three matched pairs of OCSCC patients surgically treated at the AC, but receiving adjuvant radiation at either an AC or a non-AC, were evaluated for differences in clinicopathologic variables, radiation treatment metrics, and survival outcomes. The main outcome measures were overall survival, disease-specific survival, and locoregional control rates. RESULTS: Matched pairs were closely comparable in TNM (tumor, node, metastasis) stage, age, and gender. There were no significant between-groups differences in demographic and clinicopathologic variables except for smoking status (never smokers 43.3% for AC vs. 20.8% for non-AC; P=0.037). Non-AC OCSCC patients received a significantly lower total radiation dose (P=0.0004) and lower radiation fractional dose (P=0.0002) than their AC matched-pair counterparts. AC treatment was associated with improved overall survival (P=0.005), disease-specific survival (P=0.019), and locoregional control (P=0.016). AC treatment was an independent predictor of overall survival on multivariate analysis (P=0.044), after adjustment for clinicopathologic differences between groups. CONCLUSIONS: Improved survival for combined modality treatment of OCSCC at the AC was noted on multivariate analysis. Differences in key radiation treatment metrics could explain survival differences noted in this study. LEVEL OF EVIDENCE: 4.

The residual setup errors of different IGRT alignment procedures for head and neck IMRT and the resulting dosimetric impact.

PURPOSE: To assess residual setup errors during head and neck radiation therapy and the resulting consequences for the delivered dose for various patient alignment procedures. METHODS AND MATERIALS: Megavoltage cone beam computed tomography (MVCBCT) scans from 11 head and neck patients who underwent intensity modulated radiation therapy were used to assess setup errors. Each MVCBCT scan was registered to its reference planning kVCT, with seven different alignment procedures: automatic alignment and manual registration to 6 separate bony landmarks (sphenoid, left/right maxillary sinuses, mandible, cervical 1 [C1]-C2, and C7-thoracic 1 [T1] vertebrae). Shifts in the different alignments were compared with each other to determine whether there were any statistically significant differences. Then, the dose distribution was recalculated on 3 MVCBCT images per patient for every alignment procedure. The resulting dose-volume histograms for targets and organs at risk (OARs) were compared to those from the planning kVCTs. RESULTS: The registration procedures produced statistically significant global differences in patient alignment and actual dose distribution, calling for a need for standardization of patient positioning. Vertically, the automatic, sphenoid, and maxillary sinuses alignments mainly generated posterior shifts and resulted in mean increases in maximal dose to OARs of >3% of the planned dose. The suggested choice of C1-C2 as a reference landmark appears valid, combining both OAR sparing and target coverage. Assuming this choice, relevant margins to apply around volumes of interest at the time of planning to take into account for the relative mobility of other regions are discussed. CONCLUSIONS: Use of different alignment procedures for treating head and neck patients produced variations in patient setup and dose distribution. With concern for standardizing practice, C1-C2 reference alignment with relevant margins around planning volumes seems to be a valid option.

Can positron emission tomography (PET) or PET/Computed Tomography (CT) acquired in a nontreatment position be accurately registered to a head-and-neck radiotherapy planning CT?

PURPOSE: To quantify the uncertainties associated with incorporating diagnostic positron emission tomography/CT (PET/CT) and PET into the radiotherapy treatment-planning process using different image registration tools, including automated and manual rigid body registration methods, as well as deformable image registration. METHODS AND MATERIALS: The PET/CTs and treatment-planning CTs from 12 patients were used to evaluate image registration accuracy. The PET/CTs also were used without the contemporaneously acquired CTs to evaluate the registration accuracy of stand-alone PET. Registration accuracy for relevant normal structures was quantified using an overlap index and differences in the center of mass (COM) positions. For tumor volumes, the registration accuracy was measured using COM positions only. RESULTS: Registration accuracy was better with PET/CT than with PET alone. The COM displacements ranged from 3.2 +/- 0.6 mm (mean +/- 95% confidence interval, for brain) to 8.4 +/- 2.6 mm (spinal cord) for registration with PET/CT data, compared with 4.8 +/- 1.7 mm (brain) and 9.9 +/- 3.1 mm (spinal cord) with PET alone. Deformable registration improved accuracy, with minimum and maximum errors of 1.1 +/- 0.8 mm (brain) and 5.4 +/- 1.4 mm (mandible), respectively. CONCLUSIONS: It is possible to incorporate PET and/or PET/CT acquired in diagnostic positions into the treatment-planning process through the use of advanced image registration algorithms, but precautions must be taken, particularly when delineating tumor volumes in the neck. Acquisition of PET/CT in the treatment-planning position would be the ideal method to minimize registration errors.

Intensity-modulated chemoradiation for treatment of stage III and IV oropharyngeal carcinoma: the University of California-San Francisco experience.

BACKGROUND: Treatment outcomes for stage III and IV oropharyngeal carcinoma treated with intensity-modulated radiotherapy (IMRT) and concurrent chemotherapy without prior surgical resection were reviewed. METHODS: Between April 2000 and September 2004, 71 patients underwent IMRT concurrent with chemotherapy without prior surgical resection for stage III and IV oropharyngeal carcinoma. Chemotherapy was platinum based. The gross tumor volume (GTV) received 70 Gy in 2.12 Gy per fraction. The high-risk clinical tumor volume (CTV) received 59.4 Gy in 1.80 Gy per fraction, and the low-risk CTV received 54 Gy in 1.64 Gy per fraction. RESULTS: With a median follow-up of 33 months, the 3-year local, regional, and locoregional progression-free probabilities were 94%, 94%, and 90%, respectively. The 3-year overall survival estimate was 83%. Locoregional failures occurred in the GTV in 7 patients. Acute grade 3 or 4 toxicity developed in 35 patients. A feeding gastrostomy was placed in 25 patients. Late xerostomia was grade 0 in 16 patients, grade 1 in 31 patients, and grade 2 in 24 patients at last follow-up. No patients experienced grade 3 or 4 late toxicity, except for 1 who developed osteoradionecrosis of the mandible. CONCLUSIONS: Excellent local and regional control was achieved with IMRT and concurrent chemotherapy without prior surgical resection in the treatment of stage III and IV oropharyngeal carcinoma. Significant sparing of the parotid glands and other critical normal tissues was possible using IMRT with moderate acute toxicities and minimal severe late effects.

A phase I study of SPI-077 (Stealth liposomal cisplatin) concurrent with radiation therapy for locally advanced head and neck cancer.

BACKGROUND: Liposomal cisplatin preparations have two potential advantages over the free drug when combined with radiation therapy (RT): 1) selective tumor localization, improving the therapeutic ratio, and 2) prolonged half-life, allowing more radiosensitization. We performed a Phase I study of Stealth liposomal cisplatin (SPI-077) concurrent with RT for head and neck squamous cell carcinoma (HNSCC). METHODS: Patients with Stage IVa/b HNSCC were treated with SPI-077, given intravenously twice two weeks apart, concurrent with RT (60-72 Gy in 6-7 weeks). The SPI-077 dose was escalated in standard phase I design. RESULTS: Twenty patients received 38 doses of SPI-077, escalated from 20-200 mg/m2 in six dose levels. Two of these patients received one dose because of reversible Grade 3 liver toxicity or rash. Three patients had a Grade 1, and one had a Grade 2 infusion reaction. Four patients had transiently elevated transaminases: Grade I (n = 1), Grade 2 (n = 1), and Grade 3 (n = 2). Grade 3 neutropenia occurred in one patient. There was no ototoxicity, neurotoxicity, or nephrotoxicity. In-field radiation skin and mucosal toxicities did not appear to be intensified. Ten of 17 patients (59%) finishing treatment achieved initial complete response. CONCLUSIONS: Systemic and in-field radiation toxicities of SPI-077 were minimal. Infusion reactions were minimized with a slower and more dilute initial infusion. Further dose escalation was stopped in the absence of dose-limiting toxicity to address the reformulation of the liposomally bound cisplatin. Nonetheless, this study shows that high doses of SPI-077 can be given safely. The potentially beneficial therapeutic ratio suggests that liposomal radiosensitizer preparations warrant further investigation.