Evaluating human papillomavirus testing, prevalence, and association with prognosis in head and neck squamous cell carcinoma by subsite: A national cancer database study

PURPOSE

To compare human papillomavirus (HPV) testing, prevalence, and association with prognosis between head and neck squamous cell carcinoma (HNSCC) subsites.

MATERIALS AND METHODS

This study utilized the National Cancer Database (NCDB) to identify patients diagnosed with HNSCC between 2010 and 2017. Rates of HPV testing, HPV-positivity, and changes in these rates over time were measured by subsite. The impact of HPV-positivity on overall survival across six head and neck subsites was assessed using multivariable-adjusted Cox proportional hazards analysis.

RESULTS

A total of 121,550 patients were included. Of this cohort, 87,575 (72.1%) were tested for HPV, with the oropharynx (55,049/64,158; 85.8%) displaying the highest rates of testing and the sinonasal tract (1519/2853; 53.2%) displaying the lowest testing rates. Of the 86,136 with a definitive result, 46,878 (54.4%) were HPV-positive, with the oropharynx (40,313/54,205; 74.4%) displaying the highest rates of HPV-positivity and the oral cavity (1818/11,505; 15.8%) displaying the lowest. HPV-positive malignancy was associated with significantly improved adjusted overall survival in the oropharynx (HR = 0.42 [95% CI: 0.43-0.47]), oral cavity (HR = 0.86 [95% CI: 0.79-0.95]), sinonasal tract (HR = 0.63 [95% CI: 0.48-0.83]), larynx (HR = 0.78 [95% CI: 0.71-0.87]), and hypopharynx (HR = 0.56 [95% CI: 0.48-0.66]), but not the nasopharynx (HR = 0.93 [95% CI: 0.77-1.14]).

CONCLUSION

HPV testing rates were significantly lower in non-oropharyngeal subsites. This is relevant as HPV-associated disease displayed significantly improved overall survival in both the oropharynx and four of five non-oropharyngeal subsites. While validation with prospective studies is necessary, these findings may warrant HPV testing in all HNSCC subsites.

Performance of Liquid Biopsy for Diagnosis and Surveillance of Human Papillomavirus-Associated Oropharyngeal Cancer

Importance

There is growing interest in the use of circulating plasma tumor human papillomavirus (HPV) DNA for diagnosis and surveillance of patients with HPV-associated oropharyngeal squamous cell carcinoma (OPSCC). Recent advances in the assays, combining the identification of circulating HPV tumor DNA and tumor DNA fragment analysis (tumor tissue-modified viral [TTMV]-HPV DNA), have been shown to be highly accurate. However, use of these newer techniques has been limited to small cohort studies and clinical trials.

Objective

To establish the clinical efficacy of plasma TTMV-HPV DNA testing in the diagnosis and surveillance of HPV-associated OPSCC in a contemporary clinical setting.

Design, Setting, and Participants

This retrospective observational cohort study included patients with OPSCC who underwent TTMV-HPV DNA testing between April 2020 and September 2022 during the course of routine clinical care. For the diagnosis cohort, patients with at least 1 TTMV-HPV DNA measurement prior to initiation of primary therapy were included. Patients were included in the surveillance cohort if they had at least 1 TTMV-HPV DNA test performed after completion of definitive or salvage therapy.

Main Outcomes and Measures

Per-test performance metrics, including sensitivity, specificity, positive predictive value, and negative predictive value, for TTMV-HPV DNA testing.

Results

Of 399 patients included in the analysis, 163 were in the diagnostic cohort (median [IQR] age, 63 [56-68.5] years; 142 [87.1%] male), and 290 were in the surveillance cohort (median [IQR] age, 63 [57-70] years; 237 [81.7%] male). Of the 163 patients in the diagnostic cohort, 152 (93.3%) had HPV-associated OPSCC while 11 (6.7%) had HPV-negative OPSCC. The TTMV-HPV DNA sensitivity in pretreatment diagnosis was 91.5% (95% CI, 85.8%-95.4% [139 of 152 tests]), and the specificity was 100% (95% CI, 71.5%-100% [11 of 11 tests]). In the surveillance cohort, 591 tests conducted in 290 patients were evaluated. A total of 23 patients had molecularly confirmed pathologic recurrences. The TTMV-HPV DNA test demonstrated sensitivity of 88.4% (95% CI, 74.9%-96.1% [38 of 43 tests]) and specificity of 100% (95% CI, 99.3%-100% [548 of 548 tests]) in detecting the recurrences. Positive predictive value was 100% (95% CI, 90.7%-100% [38 of 38 tests]), and negative predictive value was 99.1% (95% CI, 97.9%-99.7% [548 of 553 tests]). The median (range) lead time from positive TTMV-HPV DNA test to pathologic confirmation was 47 (0-507) days.

Conclusions and Relevance

This cohort study demonstrated that when evaluated in a clinical setting, the TTMV-HPV DNA assay demonstrated 100% specificity in both diagnosis and surveillance. However, the sensitivity was 91.5% for the diagnosis cohort and 88.4% for the surveillance cohort, signifying that nearly 1 in 10 negative tests among patients with HPV-associated OPSCC was a false negative. Additional research is required to validate the assay's performance and, if validated, then further research into the implementation of this assay into standard clinical practice guidelines will be required.

Practice Patterns and Disparities of Fractionation Schemes for Post-Mastectomy Comprehensive Nodal Irradiation

PURPOSE/OBJECTIVE(S)

Hypofractionated (HF) radiotherapy is the established standard of care for whole breast irradiation and is being investigated for comprehensive nodal irradiation, but appropriate patient selection for the latter is currently undefined. This study aims to report national practice patterns and patient selection for HF comprehensive nodal irradiation compared to conventional fractionation (CF). The hypothesis is that the rate of HF for comprehensive nodal irradiation in breast cancer has been increasing over time and is more likely to be offered to disparate demographic populations.

MATERIALS/METHODS

We queried the National Cancer Database and identified 128,693 patients who received comprehensive nodal irradiation between 2008-2016 in the United States. No patient who underwent lumpectomy received HF nodal irradiation; therefore, only post-mastectomy patients were included in this study. After the exclusion, 29,053 post-mastectomy patients with adjuvant comprehensive nodal irradiation remained. A multivariable binomial regression analysis between HF and CF patients was performed.

RESULTS

Of the patients identified, 1,910 received HF (6.57%), and 27,143 received CF (93.43%) radiotherapy. All patients had locally advanced breast cancer treated with mastectomy, lymph node dissection, adjuvant radiation, and +/- chemotherapy. The median dose in the HF group was 4,256 cGy in 16 fractions, and in the CF group was 6,040 cGy in 33 fractions. HF rate grew from 3.56% in 2004-2007, 5.29% in 2008-2011, 7.42% in 2012-2013, and 12.05% in 2014-2016. HF was favored in older patients (median age 66 vs. 51, OR = 1.16, 95% Cl 1.11-1.22) and those who lived in suburban or rural regions compared to urban or metropolitan regions (OR = 9.48, 95% CI 1.17-76.9). However, there was no correlation when distance from treatment site was evaluated as a continuous variable. A "boost" dose was used in only 10.58% of HF patients compared to 54.6% of CF patients (OR = 0.17, 95% Cl 0.14-0.21). Chemotherapy was delivered in 36.91% of HF patients compared to 78.14% of CF patients (OR = 0.77, 95% Cl 0.59-0.99). There were no statistically significant correlates of either fractionation scheme for breast laterality, stage, grade, or receptor status. Notably, other than population density and age, demographic factors including race, Hispanic origin, insurance type, median income, and education level demonstrated no correlation with radiation fractionation scheme.

CONCLUSION

HF for comprehensive nodal irradiation in breast cancer is still uncommon but growing in popularity. Currently, HF is more likely to be used in elderly patients and lower population density centers and less likely to be used in those determined to benefit from receipt of a boost or chemotherapy.

Is 80 the New 70? Octogenarians with Oropharyngeal Squamous Cell Carcinoma

PURPOSE/OBJECTIVE(S)

As the human papilloma virus (HPV) pandemic evolves and life expectancy increases, the number of older adults with oropharyngeal squamous cell carcinoma (OPSCC) continues to increase. However, there is a paucity of data regarding the fastest growing subset of this population: octogenarians (OGs). We sought to understand differences in treatment tolerability and clinical outcomes between septuagenarians (SGs) and OGs with OPSCC.

MATERIALS/METHODS

We identified SGs (age 70-79) and OGs (age 80-89) with OPSCC from a cohort of older adults with nonrecurrent, nonmetastatic head and neck squamous cell carcinoma (HNSCC) treated curatively from 2007-2020. We compared demographics, treatment characteristics and toxicities using Fischer's exact test. Time-to-event outcomes, overall survival (OS), locoregional control (LRC), and disease-specific survival (DSS), were evaluated using the Kaplan-Meier method.

RESULTS

Of 293 patients (age 70-89) with HNSCC, 39% (n = 114) had OPSCC: 93 SGs (median age: 73; interquartile range [IQR]: 71-76), and 21 OGs (median age: 81, IQR: 80-84). The median follow-up for included patients was 2.4 years; 82% were male, 64% white, 48% > 20 pack year smoking history, 37% ECOG 1. Patients had AJCC 8th edition Stage: I (27%); II (33%); III (18%); IV (22%) OPSCC. Treatment consisted of adjuvant radiation (RT) (19%), adjuvant chemoradiation (CRT) (8%), surgery alone (6%), induction/concurrent CRT (27%), concurrent CRT (28%), or RT (12%), with no significant differences in stage or treatment modalities noted between SGs and OGs. Of note, 69% of SGs and 76% of OGs were HPV+. Among 107 patients who received any RT, 24% experienced a treatment interruption (19% of SGs vs. 48% of OGs, p = 0.001) and 2 patients (both HPV- SGs) died on treatment due to unrelated health conditions. Percutaneous endoscopic gastrostomy (PEG) tubes were placed prior to or during treatment in 43% of SGs and 62% of OGs, with OGs more likely to have a PEG placed during treatment (p = 0.025). There was no difference in the prevalence of late (> 6 months) CTCAE grade 2+ dysphagia (36%) or xerostomia (31%) between SGs and OGs. Estimated 3-year LRC, DSS, and OS were not significantly different between SGs (LRC:85%; DSS:87%; OS:76%) and OGs (LRC: 81%; DSS:94%; OS: 55%, p-values: 0.98, 0.42, 0.052, respectively). However, HPV+ disease significantly increased estimated 3-year OS for both SGs (HPV+: 84%; HPV-: 56%, p = 0.0006) and OGs (HPV+: 68%; HPV-: 20%, p = 0.008).

CONCLUSION

In our cohort, OGs had a higher proportion of HPV+ OPSCC, which was associated with improved OS. This finding may provide insight into the latency of the virus. While there were similar amounts of toxicities among SGs and OGs, OGs more frequently underwent PEG tube placement and experienced more treatment interruptions. Given high rates of HPV+ OPSCC in OGs, our findings suggest that de-escalation strategies should be further investigated to improve tolerability and maximize outcomes for this neglected population.

Effect of treatment interruptions on overall survival in patients with triple-negative breast cancer

INTRODUCTION

Currently, there are no data regarding the impact of treatment interruptions during radiotherapy for breast cancer. In this study, we examine the correlation between treatment interruptions during radiotherapy and outcomes in triple-negative breast cancer patients.

METHODS

A total of 35 845 patients with triple-negative breast cancer treated between 2010 and 2014 were identified and analyzed from the National Cancer Database. The number of interrupted radiotherapy treatment days was calculated as the difference between the total elapsed days from the start to end of radiation treatment (both initial treatment and boost treatment, when boost was administered) and the total number of expected treatment days, defined as the number of expected treatment days with an addition of 2 weekend days for every multiple of 5 treatment days. Binomial multivariate regression analysis was used to detect correlates of treatment interruptions, and propensity-score matched multivariable Cox proportional hazard models were used to evaluate the association between treatment interruption and overall survival (OS).

RESULTS

When modeled as a continuous variable, longer treatment duration was associated with poorer OS (hazard ratio [HR] = 1.023, 95% confidence interval [CI] = 1.015 to 1.031). In reference to 0-1 days of interruption, patients with 2-5 interrupted days (HR = 1.069, 95% CI = 1.002 to 1.140 interrupted days), 6-10 interrupted days (HR = 1.239, 95% CI = 1.140 to 1.348 interrupted days), and 11-15 interrupted days (HR = 1.265, 95% CI = 1.126 to 1.431 interrupted days) experienced increasing likelihood of mortality.

CONCLUSION

In the first study of its kind, we report a correlation between treatment interruptions during adjuvant radiotherapy in triple-negative breast cancer and OS.

Proton Bragg Peak FLASH Enables Organ Sparing and Ultra-High Dose-Rate Delivery: Proof of Principle in Recurrent Head and Neck Cancer

Proton pencil-beam scanning (PBS) Bragg peak FLASH combines ultra-high dose rate delivery and organ-at-risk (OAR) sparing. This proof-of-principle study compared dosimetry and dose rate coverage between PBS Bragg peak FLASH and PBS transmission FLASH in head and neck reirradiation. PBS Bragg peak FLASH plans were created via the highest beam single energy, range shifter, and range compensator, and were compared to PBS transmission FLASH plans for 6 GyE/fraction and 10 GyE/fraction in eight recurrent head and neck patients originally treated with quad shot reirradiation (14.8/3.7 CGE). The 6 GyE/fraction and 10 GyE/fraction plans were also created using conventional-rate intensity-modulated proton therapy techniques. PBS Bragg peak FLASH, PBS transmission FLASH, and conventional plans were compared for OAR sparing, FLASH dose rate coverage, and target coverage. All FLASH OAR V40 Gy/s dose rate coverage was 90-100% at 6 GyE and 10 GyE for both FLASH modalities. PBS Bragg peak FLASH generated dose volume histograms (DVHs) like those of conventional therapy and demonstrated improved OAR dose sparing over PBS transmission FLASH. All the modalities had similar CTV coverage. PBS Bragg peak FLASH can deliver conformal, ultra-high dose rate FLASH with a two-millisecond delivery of the minimum MU per spot. PBS Bragg peak FLASH demonstrated similar dose rate coverage to PBS transmission FLASH with improved OAR dose-sparing, which was more pronounced in the 10 GyE/fraction than in the 6 GyE/fraction. This feasibility study generates hypotheses for the benefits of FLASH in head and neck reirradiation and developing biological models.

Combining Radiotherapy and Immunotherapy in Head and Neck Cancer

Head and neck squamous cell carcinoma (HNSCC) is a leading cause of morbidity and mortality globally. Despite significant advances in well-established treatment techniques, prognosis for advanced-stage HNSCC remains poor. Recent, accumulating evidence supports a role for immunotherapy in HNSCC treatment. Radiation therapy (RT), a standard treatment option for HNSCC, has immunomodulatory and immunostimulatory effects that may enhance the efficacy of immunotherapy. In several cancer types, combining RT and immunotherapy has been shown to improve tumor response rates, increase survival, and reduce toxicity compared to traditional chemotherapy and radiation therapy. This review provides a timely overview of the current knowledge on the use of RT and immunotherapy for treating HNSCC. It highlights the potential advantages of combining these therapies, such as improved tumor response rates, increased survival, and reduced toxicity. The review also discusses the challenges that need to be addressed when redefining the standard of care in HNSCC, and proposes further research to optimize treatment combinations, minimize radiation-induced toxicity, and identify suitable patient populations for treatment.

Rapid cancer cell perineural invasion utilizes amoeboid migration

The invasion of nerves by cancer cells, or perineural invasion (PNI), is potentiated by the nerve microenvironment and is associated with adverse clinical outcomes. However, the cancer cell characteristics that enable PNI are poorly defined. Here, we generated cell lines enriched for a rapid neuroinvasive phenotype by serially passaging pancreatic cancer cells in a murine sciatic nerve model of PNI. Cancer cells isolated from the leading edge of nerve invasion showed a progressively increasing nerve invasion velocity with higher passage number. Transcriptome analysis revealed an upregulation of proteins involving the plasma membrane, cell leading edge, and cell movement in the leading neuroinvasive cells. Leading cells progressively became round and blebbed, lost focal adhesions and filipodia, and transitioned from a mesenchymal to amoeboid phenotype. Leading cells acquired an increased ability to migrate through microchannel constrictions and associated more with dorsal root ganglia than nonleading cells. ROCK inhibition reverted leading cells from an amoeboid to mesenchymal phenotype, reduced migration through microchannel constrictions, reduced neurite association, and reduced PNI in a murine sciatic nerve model. Cancer cells with rapid PNI exhibit an amoeboid phenotype, highlighting the plasticity of cancer migration mode in enabling rapid nerve invasion.

Dosimetric Comparison of Intensity-Modulated Radiation Therapy (IMRT) and Intensity-Modulated Proton Therapy (IMPT) for a Novel Oral Tongue Avoidance Concept in Low-Risk Squamous Cell Carcinoma of the Oral Tongue

Purpose

After adequate surgical resection, early-stage oral tongue cancer patients can harbor a low risk of local recurrence but remain at risk of regional recurrence. Oral tongue avoidance during adjuvant radiation therapy is an attractive potential treatment strategy to mitigate treatment toxicity. We sought to quantify the dosimetric advantages of this approach and hypothesized that intensity-modulated proton therapy (IMPT) may further reduce organs at risk doses compared with intensity-modulated radiation therapy (IMRT).

Materials and Methods

Five patients with oral tongue cancer treated with postoperative radiation therapy from August 2020 to September 2021 were retrospectively reviewed. Novel clinical target volume contours, excluding the oral tongue, were generated while maintaining coverage of bilateral at-risk lymph nodes. Comparison IMRT (X) and IMPT (PBT) plans were generated using standard treatment volumes (control) and avoidance volumes (study) (n = 4 plans/patient). Dosimetric variables for organs at risk were compared using the paired t test.

Results

The prescribed dose was 60 Gy in 30 fractions. D95% clinical target volume coverage was similar between X and PBT plans for both control and study clinical target volumes. Comparing control with study plans, both X (58.9 Gy vs 38.3 Gy, P = .007) and PBT (60.2 Gy vs 26.1 Gy, P < .001) decreased the oral cavity dosemean. The pharyngeal constrictor dosemean was also reduced (P < .003). There was no difference between control and study plans for larynx (P = .19), parotid (P = .11), or mandible dose (P = .59). For study plans, PBT significantly reduced oral cavity dosemean (38.3 Gy vs 26.1 Gy, P = .007) and parotid dosemean (23.3 Gy vs 19.3 Gy, P = .03) compared with X. For control plans, there was no difference in oral cavity dosemean using PBT compared with X, but PBT did improve the parotid dosemean (26.6 Gy vs 19.7 Gy, P = .02).

Conclusion

This study quantifies the feasibility and dosimetric advantages of oral tongue avoidance while still treating the at-risk lymph nodes for oral tongue cancer. The dosimetric difference between PBT and X was most prominent with an oral tongue-avoidance strategy.

Close Margins After Transoral Robotic Surgery for Human Papillomavirus-Positive Oropharyngeal Carcinoma: A Review of the Literature and Practical Recommendations

The purpose of this article is to summarize the literature and practical recommendations from experienced centers for close margins after transoral robotic surgery for human papillomavirus-positive oropharyngeal carcinoma.

Clinical and Therapeutic Considerations for Older Adults with Head and Neck Cancer

Approximately 30% of patients with head and neck squamous cell carcinoma (HNSCC) are at least 70 years of age, and this percentage is expected to increase as the population increases and lives longer. Elderly patients are underrepresented in head and neck oncology clinical trials, and there is minimal evidence on the management of HNSCC for this population. Subsequently, despite their best intentions, physicians may unknowingly recommend an ill-suited course of therapy, which may result in suboptimal oncological or functional outcomes or adverse events. Surgical approaches have the potential to carry a higher risk of morbidity and mortality in older adults, especially in patients with multiple comorbidities. Definitive radiation therapy treatment in patients with HNSCC frequently involves 7 weeks of daily radiation, sometimes with concurrent chemotherapy, and this demanding treatment can be difficult for older adult patients, which may lead to treatment interruptions, potential removal of concurrent systemic therapy, compromised outcomes, and diminished quality of life. There are clinical trials currently underway investigating altered fractionation regimens and novel, less toxic systemic treatments in this population. This review provides an overview of how best to approach an older adult with HNSCC, from initial work-up to treatment selection.

The Sinai Robotic Surgery Trial in HPV-related oropharyngeal squamous cell carcinoma (SIRS 2.0 trial) – study protocol for a phase II non-randomized non-inferiority trial

Background

Human papillomavirus associated oropharyngeal squamous cell carcinoma (HPVOPSCC) usually affects a younger patient population. As such, the risk for long term toxicity associated with therapy is an important consideration. Multiple trials focused on de-escalation of therapy to preserve survival outcomes while minimizing treatment toxicity are currently in progress, however the question of which patients are ideal candidates for de-escalation remains unanswered. Circulating tumor DNA (cfHPVDNA) has emerged as a means of monitoring disease in patients with HPVOPSCC. Undetectable postoperative cfHPVDNA levels portend a better prognosis and by extension, may identify ideal candidates for de-escalation therapy. We propose an overview and rationale for a new institutional clinical trial protocol focusing on the use of cfHPVDNA to risk stratify patients for adjuvant therapy. We hypothesize that many surgical patients currently receiving radiation therapy may be clinically observed without adjuvant therapy.

Methods

Patients with measurable cfHPVDNA and clinically resectable HPVOPSCC will undergo TORS resection of tumors and neck dissection. Patients with undetectable cfHPVDNA at 3 weeks post-op will be allocated to low or high-risk treatment protocol groups. The low risk group consists of patients with <4 positive lymph nodes, ≤2 mm extranodal extension (ENE), and perineural invasion (PNI) or lymphovascular invasion (LVI) alone. The high-risk group is made up of patients with ≥4 positive lymph nodes, gross ENE, positive margins, N2c disease and/or the combination of both PNI and LVI. The low-risk group will be allocated to an observation arm, while the high-risk group will receive 46 Gy of adjuvant radiotherapy and weekly cisplatin therapy. The primary outcome of interest is 2-year disease recurrence with secondary outcomes of 2-year disease free survival, locoregional control, overall survival, and quality of life measures. A sample of 126 patients in the low-risk group and 73 patients in the high-risk group will be required to evaluate non-inferiority to the standard of care.

Discussion

This study will provide much needed recurrence and survival data for patients that undergo primary TORS followed by observation or de-escalated adjuvant therapy. Additionally, it will help delineate the role of cfHPVDNA in the risk stratification of patients that undergo treatment de-intensification.

High Failure Rates in Young Nonsmoker Nondrinkers With Squamous Cell Carcinoma of the Oral Tongue

OBJECTIVE(S)

There has been a disproportionate increase in the incidence of young patients with squamous cell carcinoma of the oral tongue (SCCOT). The purpose of this study was to compare young patients to older patients with SCCOT without prior drinking or smoking history as this population is poorly characterized in the literature.

METHODS

A retrospective review of patients presenting to our institution with SCCOT was performed. The clinical and pathologic characteristics, as well as, outcomes were compared between younger patients (age ≤45) and older patients (age >45). Outcome analysis was performed using Kaplan Meier method. Multivariable Cox proportional hazard models were performed for age and stage.

RESULTS

Eighty-two patients (38 young, 44 old) were included in this study. Median follow-up was 29.4 months. When compared to the older cohort (age >45), the younger cohort (age ≤45) demonstrated lower rates of 5-year locoregional control (LC) (79.6% vs. 52.5%, p = 0.043) and distant metastasis-free survival (88.1% vs. 61.8%, p = 0.006). Both cohorts demonstrated similar overall survival rates (55.5% vs. 58.1%) and disease-specific survival (66.2% vs. 58.1%). Of patients experiencing locoregional failure with available radiation therapy plans and PET scans in younger cohorts (n = 7), 100% demonstrated in-field failures. Multivariable Cox proportional hazards demonstrated age was an independent predictor of DMFS (p = 0.004) and the advanced stage was a predictor of DSS (p = 0.03).

CONCLUSIONS

Young, nondrinker, nonsmokers with SCCOT demonstrate high rates of locoregional recurrence, distant metastasis, and in-field failures. Future studies are warranted to determine underlying mechanisms driving pathogenesis in this unique cohort.

LEVEL OF EVIDENCE

3 Laryngoscope, 2022.

Management of Older Adults with Locally Advanced Head and Neck Cancer

Simple Summary

Approximately one third of patients with head and neck cancer are older adults. The number of older adults with head and neck cancer continues to rise especially as life expectancy increases. However, this population remains significantly underrepresented in clinical trials. Due to this, there is no clear consensus regarding the optimal treatment for older adults with head and neck cancer. In general, older adults are a complex cohort due to variations in functional and performance status, medical comorbidities, and medication management. Treatment for head and neck cancer involves surgery, radiation therapy, systemic therapy, or a combination. These treatments are highly demanding. Additionally, they are associated with toxicity which can be especially difficult for older adults to tolerate. This may lead to treatment interruptions and compromised outcomes. In order to understand the optimal treatment for older adults with head and neck cancer, novel predictive scores are being developed. Additionally, ongoing clinical trials are investigating less intensive treatments for older adults. This review provides an overview of current clinical data, treatment considerations, and future areas of investigation for older adults with head and neck cancer.

Abstract

Thirty percent of patients with head and neck squamous cell carcinoma (HNSCC) are at least 70 years of age. This number continues to rise as life expectancy continues to increase. Still, older adults with HNSCC remain underrepresented in clinical trials, resulting in ambiguity on optimal management. Older adults are a complex patient population, often requiring increased support due to issues relating to functional and performance status, medical comorbidities, and medication management. Furthermore, in older adults with HNSCC, many of these conditions are independently associated with increased toxicity and worse outcomes. Toxicity in the older adult remains difficult to predict and to understand, and as treatment decisions are based on treatment tolerability, it is essential to understand the toxicities and how to minimize them. Novel predictive scores are being developed specifically for older adults with HNSCC to understand toxicity and to assist in personalized treatment decisions. There are clinical trials presently underway that are investigating shortened radiation courses and novel, less toxic systemic treatments in this population. In the forthcoming sections, we provide a detailed overview of the clinical data, treatment paradigms, and considerations in this population. This review provides a comprehensive overview of existing clinical data and clinical considerations in the older adult head and neck cancer population. Additionally, we provide a detailed overview of pertinent current and ongoing clinical trials, as well as future areas for investigation.

Cluster model incorporating heterogeneous dose distribution of partial parotid irradiation for radiotherapy induced xerostomia prediction with machine learning methods

PURPOSE

A cluster model incorporating heterogeneous dose distribution within the parotid gland was developed and validated retrospectively for radiotherapy (RT) induced xerostomia prediction with machine learning (ML) techniques.

METHODS

Sixty clusters were obtained at 1 Gy step size with threshold doses ranging from 1 to 60 Gy, for each of the enrolled 155 patients with HNC from three institutions. Feature clusters were selected with the neighborhood component analysis (NCA) and subsequently fed into four supervised ML models for xerostomia prediction comparison: support vector machines (SVM), k-nearest neighbor (kNN), naïve Bayes (NB), and random forest (RF). The predictive performance of each model was evaluated using cross validation resampling with the area-under-the-curves (AUC) of the receiver-operating-characteristic (ROC). The xerostomia predicting capacity using testing data was assessed with accuracy, sensitivity, and specificity for these models and three cluster connectivity choices. Mean dose based logistic regression served as the benchmark for evaluation.

RESULTS

Feature clusters identified by NCA fell in three threshold dose ranges: 5-15Gy, 25-35Gy, and 45-50Gy. Mean dose predictive power was 15% lower than that of the cluster model using the logistic regression classifier. Model validation demonstrated that kNN model outperformed slightly other three models but no substantial difference was observed. Applying the fine-tuned models to testing data yielded that the mean accuracy from SVM, kNN and NB models were between 0.68 and 0.7 while that of RF was ∼0.6. SVM model yielded the best sensitivity (0.76) and kNN model delivered consistent sensitivity and specificity. This is consistent with cross validation. Clusters calculated with three connectivity choices exhibited minimally different predictions.

CONCLUSION

Compared to mean dose, the proposed cluster model has shown its improvement as the xerostomia predictor. When combining with ML techniques, it could provide a clinically useful tool for xerostomia prediction and facilitate decision making during radiotherapy planning for patients with HNC.

Retreatment of Recurrent or Second Primary Head and Neck Cancer After Prior Radiation: Executive Summary of the American Radium Society® (ARS) Appropriate Use Criteria (AUC): Expert Panel on Radiation Oncology - Head and Neck Cancer

BACKGROUND

Re-treatment of recurrent or second primary head and neck cancers occurring in a previously irradiated field is complex. Few guidelines exist to support practice.

METHODS

We performed an updated literature search of peer-reviewed journals in a systematic fashion. Search terms, key questions, and associated clinical case variants were formed by panel consensus. The literature search informed the committee during a blinded vote on the appropriateness of treatment options via the modified Delphi method.

RESULTS

The final number of citations retained for review was 274. These informed five key questions, which focused on patient selection, adjuvant re-irradiation, definitive re-irradiation, stereotactic body radiation (SBRT), and re-irradiation to treat non-squamous cancer. Results of the consensus voting are presented along with discussion of the most current evidence.

CONCLUSIONS

This provides updated evidence-based recommendations and guidelines for the re-treatment of recurrent or second primary cancer of the head and neck.

Moving beyond Definitive Therapy: Increasing Physical Activity in Survivors of Cancers of the Head and Neck

As chemotherapeutic, radiation, and surgical techniques have improved, there has been a dramatic improvement in survival in patients diagnosed with cancers of the head and neck. As a result, a heightened focus on survivorship by clinicians will increasingly prove necessary. In particular, medical care teams will have to pay special attention to mitigating the long-term sequelae of definitive cancer treatments, many of which act as barriers to exercise. This is unfortunate, as the benefits of exercise in patients with cancer have become increasingly recognized. In this review, we discuss the potential benefits of and barriers to exercise in survivors of cancers of the head and neck. We also review existing exercise guidelines and strategies by which clinicians can promote exercise in this unique patient population.

Functional Larynx Preservation in Patients With Locally Advanced Squamous Cell Carcinoma of the Larynx and Hypopharynx Treated With Induction Chemotherapy vs. Concurrent Chemoradiation Alone

Objectives

Chemoradiation therapy (CRT) has been established as a standard treatment for locally advanced hypopharynx/larynx squamous cell carcinoma (SCC) but the role of induction chemotherapy (IC) remains unclear. The primary outcome of this study is to determine whether functional larynx-preservation survival (FLPS) is improved with the addition of IC in these patients. Secondary outcomes were overall survival (OS), progression-free survival (PFS), distant metastasis-free survival (DMFS), and laryngectomy rates.

Methods

Records for patients with AJCC 8th edition clinical stage III-IVB laryngeal and hypopharyngeal SCC treated with CRT +/- IC from 2005-2019 were reviewed. FLPS was defined as time until death, progression, laryngectomy, or non-functional larynx. Kaplan-Meier curves were generated for FLPS, OS, PFS, and DMFS. Outcomes were compared using the stratified log-rank test. Laryngectomy rates were compared using Fisher’s exact test.

Results

We included 52 patients with laryngeal and 38 with hypopharyngeal SCC (n=90); 19 patients with laryngeal SCC and 19 with hypopharyngeal SCC received IC (median three cycles). There were no differences in the three-year FLPS (61% vs 67.8%; p=0.88), OS (73.9% vs 86.2%; p=0.42), PFS (53.6% vs 62.6%; p=0.44), or DMFS (65.2% vs 71.5%, p= 0.85) between patients who did and did not receive IC all patients. Laryngectomy rates did not differ with and without IC (18.4 % vs 7.7%; p=0.19).

Conclusion

In this study of advanced laryngeal and hypopharyngeal SCC, IC did not improve three-year FLPS, OS, PFS, or laryngectomy rates compared to CRT alone. A large prospective series would provide a more robust understanding of the role of IC in this group of patients. 

Clinical Review of Proton Therapy in the Treatment of Unilateral Head and Neck Cancers

Radiotherapy is a common treatment modality in the management of head and neck malignancies. In select clinical scenarios of well-lateralized tumors, radiotherapy can be delivered to the primary tumor or tumor bed and the ipsilateral nodal regions, while intentional irradiation of the contralateral neck is omitted. Proton beam therapy is an advanced radiotherapy modality that allows for the elimination of exit-dose through nontarget tissues such as the oral cavity. This dosimetric advantage is apt for unilateral treatments. By eliminating excess dose to midline and contralateral organs at risk and conforming dose around complex anatomy, proton beam therapy can reduce the risk of iatrogenic toxicities. Currently, there is no level I evidence comparing proton beam therapy to conventional photon radiation modalities for unilateral head and neck cancers. However, a growing body of retrospective and prospective evidence is now available describing the dosimetric and clinical advantages of proton beam therapy. Subsequently, the intent of this clinical review is to summarize the current evidence supporting the use of proton beam therapy in unilateral irradiation of head and neck cancers, including evaluation of disease site-specific evidence, unique challenging clinical scenarios, and ongoing clinical trials.

De-Escalated Adjuvant Therapy After Transoral Robotic Surgery for Human Papillomavirus-Related Oropharyngeal Carcinoma: The Sinai Robotic Surgery (SIRS) Trial

BACKGROUND

Treatment of human papillomavirus-related oropharyngeal squamous cell carcinoma (HPVOPC) results in unprecedented high survival rates but possibly unnecessary toxicity. We hypothesized that upfront surgery and neck dissection followed by reduced-dose adjuvant therapy for early and intermediate HPVOPC would ultimately result in equivalent progression-free survival (PFS) and overall survival while reducing toxicity.

METHODS

This study was a nonrandomized phase II trial for early-stage HPVOPC treated with transoral robotic surgery (TORS) followed by reduced-dose radiotherapy. Patients with previously untreated p16-positive HPVOPC and <20 pack years' smoking history were enrolled. After robotic surgery, patients were assigned to group 1 (no poor risk features; surveillance), group 2 (intermediate pathologic risk factors [perineural invasion, lymphovascular invasion]; 50-Gy radiotherapy), or group 3 (poor prognostic pathologic factors [extranodal extension [ENE], more than three positive lymph nodes and positive margin]; concurrent 56-Gy chemoradiotherapy with weekly cisplatin).

RESULTS

Fifty-four patients were evaluable; there were 25 in group 1, 15 in group 2, and 14 in group 3. Median follow-up was 43.9 months (9.6-75.8). Disease-specific survival was 98.1%, and PFS was 90.7%. PFS probability via Kaplan-Meier was 91.3% for group 1, 86.7% for group 2, and 93.3% for group 3. There were five locoregional failures (LRFs), including one distant metastasis and one contralateral second primary. Average time to LRF was 18.9 months (9.6-59.0); four LRFs were successfully salvaged, and the patients remain disease free (11.0-42.7 months); one subject remains alive with disease.

CONCLUSION

The results indicate that upfront surgery with neck dissection with reduced-dose radiation for T1-2, N1 stage (by the eighth edition American Joint Committee on Cancer staging manual) HPVOPC results in favorable survival with excellent function in this population. These results support radiation dose reduction after TORS as a de-escalation strategy in HPVOPC.

IMPLICATIONS FOR PRACTICE

Transoral robotic surgery can provide a safe platform for de-escalation in carefully selected patients with early-stage human papillomavirus-related oropharyngeal cancer. In this clinical trial, disease-specific survival was 100%, over 90% of the cohort had a reduction of therapy from standard of care with excellent functional results, and the five patients with observed locoregional failures were successfully salvaged.

Promoting exercise in patients with cancers of the head and neck during COVID-19 and beyond

In recent years, the benefits of exercise in patients with cancer have increasingly been recognised. Unfortunately, patients with, and survivors of, cancers of the head and neck often face a constellation of symptomatic and nutritional obstacles that can interfere with their ability to adhere to structured exercise regimens. The spread of COVID-19 has only added to these challenges. In this Viewpoint, the authors detail the impediments faced by patients with cancers of the head and neck in obtaining sufficient exercise, review the evidence supporting the benefits of exercise in patients with cancer and discuss interventions to promote exercise in this patient population.

Primary Mediastinal B Cell Lymphoma in the Positron-Emission Tomography Era Executive Summary of the American Radium Society Appropriate Use Criteria

PURPOSE

Primary mediastinal B cell lymphoma (PMBCL) is a highly curable subtype of non-Hodgkin lymphoma that is diagnosed predominantly in adolescents and young adults. Consequently, long-term treatment-related morbidity is critical to consider when devising treatment strategies that include different chemoimmunotherapy strategies with or without radiation therapy. Furthermore, adaptive approaches using the end-of-chemotherapy (EOC) positron emission tomography (PET)/computed tomography (CT) scanning may help to determine which patients may benefit from additional therapies. We aimed to develop evidence-based guidelines for treating these patients.

METHODS AND MATERIALS

We conducted a systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline using the PubMed database. The ARS expert committee, composed of radiation oncologists, hematologists, and pediatric oncologists, developed consensus guidelines using the modified Delphi framework.

RESULTS

Nine studies met the full criteria for inclusion based on reporting outcomes on patients with primary mediastinal B cell lymphoma with EOC PET/CT response scored with the 5-point Deauville scale. These studies formed the evidence for these guidelines in managing patients with PMBCL according to the EOC PET response, including after a 5-point Deauville scale of 1 to 3, 4, or 5, and for patients with relapsed and refractory disease. The expert group also developed guidance on radiation simulation, treatment planning, and plan evaluation based on expert opinion.

CONCLUSIONS

Various treatment approaches exist in the management of PMBCL, including different chemoimmunotherapy regimens, the use of consolidative radiation therapy, and adaptive approaches based on EOC PET/CT response. These guidelines can be used by practitioners to provide appropriate treatment according to different disease scenarios.

Redefining risk of contralateral cervical nodal disease in early stage oropharyngeal cancer in the human papillomavirus era

BACKGROUND

The optimal extent of surgery and/or radiation to the contralateral lymph node region is unknown in early-stage human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma (OPSCC).

METHODS

To investigate the pathologic incidence of and risk factors for contralateral nodal disease (CND) in cT1-T2 HPV-related OPSCC treated with transoral robotic surgery (TORS) and bilateral neck dissection (BND), the records of 120 patients were reviewed.

RESULTS

Eleven patients displayed pathologic contralateral nodal disease (pCND), including 7.1% of tonsil and 10.9% of base of tongue (BOT) cases. Medial hemistructure involvement and cN2 disease were significantly associated with pCND. Zero cN0 patients had pCND, and on multivariate analysis only cN classification remained significantly associated with pCND. Four percent of BOT patients and 2% of tonsil patients with a well-lateralized primary and cN0/N1 neck demonstrated pCND.

CONCLUSIONS

HPV-related OPSCC that are cN0-N1 have exceedingly low rates of pCND. Well-lateralized HPV-related BOT primaries with limited clinical nodal disease may be candidates for ipsilateral only treatment.

Systematic review of postoperative therapy for resected squamous cell carcinoma of the head and neck: Executive summary of the American Radium Society appropriate use criteria

BACKGROUND

The aims of this systematic review are to (a) evaluate the current literature on the impact of postoperative therapy for resected squamous cell carcinoma of the head and neck (SCCHN) on oncologic and non-oncologic outcomes and (b) identify the optimal evidence-based postoperative therapy recommendations for commonly encountered clinical scenarios.

METHODS

An analysis of the medical literature from peer-reviewed journals was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guideline. Prospective studies and methodology-based systematic reviews and meta-analyses of postoperative therapy for SCCHN were identified by searching Medline (OVID) and EMBASE (Elsevier) using controlled vocabulary terms (ie, National Library of Medicine Medical Subject Headings [MeSH], EMTREE). Study screening and selection was performed with Covidence software and full-text review. The RAND/UCLA appropriateness method was used by the expert panel to rate the appropriate use of postoperative therapy, and the modified Delphi method was used to come to consensus.

RESULTS

A total of 5660 studies were identified and screened using the title and abstract, leading to 201 studies assessed for relevance using full-text review. After limitation to the eligibility criteria, 101 studies from 1977 to 2020 were identified, including 77 with oncologic endpoints and 24 with function and quality of life endpoints. All studies reported staging prior to the implementation of American Joint Committee on Cancer (AJCC-8).

CONCLUSIONS

Prospective clinical studies and systematic reviews identified through the PRISMA systematic review provided good evidence for consensus statements regarding the appropriate use of postoperative therapy for resected SCCHN. Further research is needed in domains where consensus by the expert panel could not be achieved for the appropriateness of specific postoperative therapeutic interventions.

Ipsilateral radiation for squamous cell carcinoma of the tonsil: American Radium Society appropriate use criteria executive summary

BACKGROUND

We conducted the current systemic review to provide up-to-date literature summary and optimal evidence-based recommendations for ipsilateral radiation for squamous cell carcinoma of the tonsil.

METHODS

We performed literature search of peer-reviewed journals through PubMed. The search strategy and subject-specific keywords were developed based on the expert panel's consensus. Articles published from January 2000 to May 2020 with full text available on PubMed and restricted to the English language and human subjects were included. Several prespecified search terms were used to identify relevant publications and additional evidence published since the initial American College of Radiology Appropriateness Criteria Ipsilateral Tonsil Radiation recommendation was finalized in 2012. The full bibliographies of identified articles were reviewed and irrelevant studies were removed.

RESULTS

The initial search and review returned 46 citations. The authors added three citations from bibliographies, websites, or books not found in the literature search. Of the 49 citations, 30 citations were retained for further detailed review, and 14 of them were added to the evidence table. Articles were removed from the bibliography if they were not relevant or generalizable to the topic, or focused on unknown primary disease. Several commonly encountered clinical case variants were created and panelists anonymously rated each treatment recommendation. The results were reviewed and disagreements discussed.

CONCLUSIONS

The panel provided updated evidence and recommendations for ipsilateral radiation for squamous cell carcinoma of the tonsil in the setting of primary radiation-based therapy and postoperative adjuvant radiotherapy. This committee did not reach agreements for some case variants due to a lack of strong evidence supporting specific treatment decisions, indicating a further need for research in these topics.

Treatment tolerability and outcomes in elderly patients with head and neck cancer

PURPOSE

The number of elderly patients with head and neck squamous cell carcinoma (HNSCC) continues to grow. Management of this cohort remains poorly defined. We investigated treatment tolerability and clinical outcomes in this underrepresented population.

METHODS

We identified patients aged ≥70 with nonrecurrent, nonmetastatic HNSCC treated curatively from 2007-2018 and analyzed clinical covariates.

RESULTS

Two hundred and twenty patients with a median age of 75 (interquartile range:72-80) were identified. Age and comorbidities were not correlated with toxicity (P ≥ .05). Patients who experienced a treatment interruption had significantly greater weight loss (P = .042) and worse overall survival (OS) (P < .001), but not worse disease-specific survival (P = .45), or locoregional control (P = .21).

CONCLUSIONS

Treatment interruptions were associated with weight loss and worse OS, but not disease related outcomes, suggesting an interruption in the elderly may be a surrogate for another issue. In sum, our data should guide clinical trial design to benefit this growing, neglected cohort.

The prognostic significance of human papilloma virus in sinonasal squamous cell carcinoma

BACKGROUND

Human papilloma virus (HPV) has been implicated in the pathology of oropharyngeal head and neck cancers, but its role in sinonasal squamous cell carcinoma (SNSCC) has not been well established.

METHODS

Thirty-two patients with SNSCC diagnosed between 2011 and 2018 were identified and stratified by HPV status and viral serotype, as determined by PCR. Endpoints including recurrence, metastases and survival were analyzed using the Kaplan-Meier method.

RESULTS

Seventeen (53%) patients were HPV-positive and 15 (47%) were HPV-negative. The median follow-up time of living patients was 30.7 months (range 4-123 months). Survival did not differ by HPV status, but HPV+ tumors were more likely to locally recur and metastasize. When stratifying by treatment type, the lowest rate of recurrence occurred in patients receiving surgery and chemoradiation.

CONCLUSION

A significant proportion of sinonasal tumors appear to be associated with HPV. Testing for HPV might be justified in all cases of sinonasal cancers. Further investigation is warranted to better understand the role of HPV in SNSCC.

Human papillomavirus genotype distribution in head and neck cancer: Informing developing strategies for cancer prevention, diagnosis, treatment and surveillance

Current clinical practice algorithms for HPV testing make no effort to discern the impact of genotypes for patients with head and neck squamous cell carcinoma (HNSC). Data was collected for all patients with HNSCs that had undergone HPV testing at an academic hospital as part of clinical care (2012-2019). Screening was performed using real-time PCR targeting L1 of low and high-risk HPV types, followed by genotyping of positive cases. Genotype status was correlated with age, site and histologic parameters. Of the 964 patients tested, 68% had HPV-positive cancers. Most arose from the oropharynx (OP) (89%) and sinonasal tract (5%). The most frequent genotype was 16 (84.4%) followed by 35 (5.6%), 33 (4.1%), 18 (2.7%), 45 (1.1%), 69 (0.8%) and others (1.3%). There was an association between genotype (16 vs non-16) and tumor origin (OP vs non-OP) (p < 0.0001). HPV18 was associated with transformation to an aggressive small cell phenotype, but HPV16 was not (22% vs 0%, p < 0.0001). Patients with HPV-non-16 OP carcinomas were older than patients with HPV16 OP carcinomas, but the difference was not significant. HPV genotypes are variable and unevenly distributed across anatomic sites of the head and neck. The association of HPV18 with small cell transformation suggests that variants can track with certain phenotypes in ways that may account for differences in clinical behavior. This study challenges the prevailing assumption of HPV equivalency across all high-risk genotypes in ways that may inform preventive, diagnostic, therapeutic and surveillance strategies.

A new face of the HPV epidemic: Oropharyngeal cancer in the elderly

OBJECTIVES

As the human papillomavirus (HPV) epidemic continues to grow, the number of elderly patients with oropharyngeal squamous cell carcinoma (OPSCC) is rapidly increasing. Despite this observation, this cohort remains understudied. We aimed to understand HPV prevalence and characteristics within this cohort as well as its impact on disease control in elderly patients.

METHODS AND MATERIALS

We identified patients aged ≥70 with newly diagnosed, non-metastatic, OPSCC treated with curative intent at our institution from 2007 to 2018. Logistic regression and survival analyses were used for outcome-specific endpoints.

RESULTS

In total, 88 patients were identified with a median age of 73 (interquartile range [IQR]: 71-78) and a median Charlson Comorbidity Index of 6 (IQR: 5-7). Eighty-two percent were ECOG 0 or 1 performance. Of note, 70% of the cohort had HPV+ tumors. Fifty-one percent of patients were AJCC 8th edition stage I/II and 49% were stage III/IV. Median follow-up time was 2.5 years (IQR: 0.9-4.7). Eight percent had surgery alone, 27% underwent adjuvant RT, and 64% received definitive RT. Sixty-four percent received concurrent chemotherapy. By both univariate and multivariable analyses, HPV+ status was significantly associated with improved locoregional control (LRC), overall survival (OS), and disease specific survival (DSS).

CONCLUSIONS

In our cohort of elderly patients with OPSCC, the majority was HPV+, which was associated with improved clinical outcomes. There are many challenges when managing elderly patients with OPSCC, but as the population ages and the HPV epidemic evolves, these patients should be considered for elderly specific clinical trials.

Long-term outcomes in patients with recurrent human papillomavirus-positive oropharyngeal cancer after upfront transoral robotic surgery

BACKGROUND

Clinical course following failure of human papillomavirus (HPV)-positive oropharyngeal cancers (HPV + OPC) is poorly understood. This study aims to characterize disease course following failure after transoral robotic surgery (TORS).

METHODS

We identified patients with HPV + OPC-treated upfront with TORS at our institution from 2007 to 2017. HPV status was confirmed with immunohistochemistry or HPV DNA polymerase chain reaction. Patient characteristics, treatment modalities, and post-recurrence outcomes were analyzed for the recurrent cohort.

RESULTS

Of the 317 HPV + OPC patients, 28 (8.8%) experienced recurrence, all of HPV 16/18 subtypes. Median post-recurrence survival was 19.8 months (range 2.3-195.8 months) in the 12 locoregional and 16 months (range 2.4-79.5 months) in the 14 distant failures. Sixteen are alive with a median of 39.8 months (range 5.5-209.4 months) after retreatment.

CONCLUSION

This is one of the largest series evaluating survival following TORS failure in HPV + OPC. Despite failure, long-term survival and durable remission are possible with single-modal or multiple-modal salvage treatment.

A Rare Case of a Transgender Female With Breast Implant-Associated Anaplastic Large Cell Lymphoma Treated With Radiotherapy and a Review of the Literature

We are reporting a case of a 54-year-old transgender female with a history of breast augmentation with bilateral silicone implants. Seventeen years later, she presented with an enlarging right breast mass. Pathology confirmed breast implant–associated anaplastic large cell lymphoma (Ann Arbor Stage IIE, TNM Stage III BIA-ALCL). The patient underwent bilateral capsulectomy, sentinel lymph node biopsy with adjuvant CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) chemotherapy, and radiotherapy to the right chest, axilla, and supraclavicular lymph nodes. BIA-ALCL is a rare entity, especially in transgender females. We report this case and a review of the literature in this report.

Cdc42 Mediates Cancer Cell Chemotaxis in Perineural Invasion

Perineural invasion (PNI) is an ominous form of cancer progression along nerves associated with poor clinical outcome. Glial derived neurotrophic factor (GDNF) interacts with cancer cell RET receptors to enable PNI, but downstream events remain undefined. We demonstrate that GDNF leads to early activation of the GTPase Cdc42 in pancreatic cancer cells, but only delayed activation of RhoA and does not affect Rac1. Depletion of Cdc42 impairs pancreatic cancer cell chemotaxis toward GDNF and nerves. An siRNA library of guanine nucleotide exchange factors was screened to identify activators of Cdc42. ARHGEF7 (β-Pix) was required for Cdc42 activation and chemotaxis toward nerves, and also colocalizes with RET under GDNF stimulation. Cdc42 enables PNI in an in vitro dorsal root ganglia coculture model, and controls the directionality of migration but does not affect cell speed or cell viability. In contrast, Rac1 was necessary for cell speed but not directionality, while the RhoA was not necessary for either cell speed or directionality. Cdc42 was required for PNI in an in vivo murine sciatic nerve model. Depletion of Cdc42 significantly diminished the length of PNI, volume of PNI, and motor nerve paralysis resulting from PNI. Activated Cdc42 is expressed in human salivary ductal cancer cells invading nerves. These findings establish the GDNF-RET-β-Pix-Cdc42 pathway as a directional regulator of pancreatic cancer cell migration toward nerves, highlight the importance of directional migration in PNI, and offer novel targets for therapy. IMPLICATIONS: Cdc42 regulates cancer cell directional migration toward and along nerves in PNI.

Rapid in-field failures following adjuvant radiation for buccal squamous cell carcinoma

OBJECTIVES/HYPOTHESIS

Squamous cell carcinoma originating in the buccal mucosa and retromolar trigone (RMT) have historically poor outcomes. Difficulties in discriminating tumor origin often result in these subsites being combined in surgical and pathological reports. We aimed to determine if making this anatomical distinction has implications for treatment design and clinical outcomes.

STUDY DESIGN

Retrospective case series.

METHODS

We identified 27 tumors from either the buccal mucosa patients or RMT patients who underwent surgery followed by radiation. For patients who developed a local failure, we fused the pretreatment imaging, simulation computed tomography, and follow-up imaging to determine the location of failures relative to the radiation field. We calculated the 2-year locoregional control and 2-year disease-free survival.

RESULTS

The median time from surgery to radiation was 50 days (range, 32-133 days). The 2-year locoregional control for buccal mucosa versus RMT, respectively, were 35.9% versus 68.4% (P = .252). The 2-year disease-free survival rates were 32.7% versus 68.4%, respectively (P = .196). The median times to failure were 12.00 months (range, 4.9-115.0 months) versus 18.5 months (range, 4.5-61.0 months), respectively. All buccal mucosa failures occurred within the high-dose planning target volume, with a median dose of 60 Gy within the failure region. Following locoregional failure, 10 of the 12 patients have died, with a median time from local failure to death of 3.6 months (range, 1-17.6 months).

CONCLUSIONS

Squamous cell carcinomas of the buccal mucosa appear to have a poor prognosis characterized by rapid in-field failure. Therefore, differentiating tumor origin may be important for prognostication and treatment.

LEVEL OF EVIDENCE

3 Laryngoscope, 130:413-417, 2020.

Risk of prolonged opioid use among cancer patients undergoing curative intent radiation therapy for head and neck malignancies

OBJECTIVE

Patients undergoing radiation treatment (RT) for head and neck malignancies often suffer significant disease- and treatment-related pain requiring opioids for effective management. However, the prevalence and associated risk factors of prolonged opioid use in this population remain poorly characterized. We sought to quantify the rate of prolonged opioid use among opioid naïve patients receiving curative-intent RT for head and neck malignancies and to identify associated risk factors.

METHODS

We retrospectively identified patients who had undergone RT for head and neck malignancies at our institution between Jan 2011 and Sept 2017. Our primary endpoint was persistent opioid use 6-months following completion of RT. Patients were included if they were opioid-naïve, underwent curative intent RT, had adequate follow-up, and did not have residual or recurrent disease within our follow-up period. Univariable and multivariable logistic regression was utilized to identify risk factors for prolonged opioid use.

RESULTS

We identified 311 patients meeting our inclusion criteria; 40 (12.9%) continued to use opioids 6-months following RT. Univariable analysis found current smoking, alcohol abuse, RT dose, treatment to the bilateral necks, induction chemotherapy, concurrent chemotherapy, PEG tube, daily milligram morphine equivalents, and adjuvant analgesic medication use to be positively associated with prolonged opioid use; prior surgery was negatively associated with prolonged opioid use. Delivery of induction chemotherapy (OR 2.86, CI (95%) 1.32-6.21) and alcohol abuse (OR 3.75, CI (95%) 1.66-8.47) remained statistically significant on multivariable analysis.

CONCLUSION

The prevalence of prolonged opioid use in previously opioid naïve patients undergoing curative intent head and neck RT was just under 13%. Patients with history of alcohol abuse and those who undergo induction chemotherapy were most at risk.

Dose Selection for Multiple Myeloma in Modern Era

PURPOSE

The management of multiple myeloma (MM) has evolved over the past 20 years, secondary to novel biologic therapeutics. Radiation therapy remains an important intervention in the management of painful lytic bone lesions. However, the currently used radiation therapy regimens were developed in the pre-biologic therapy era. The goal of this study is to assess the effects of dose and fractionation in pain control for patients with MM in the modern era.

METHODS AND MATERIALS

We conducted a retrospective study based on data collected from patients who received radiation therapy at our institute between 2007 and 2017. A total of 130 patients (266 treatment sites) were included in this study. Univariate Cox proportional hazards models were used to analyze the association of risk of pain recurrence with treatment characteristics and compute the hazard ratios (HRs).

RESULTS

The median follow-up time was 14 months. Patients who received a total dose of 20 to <30 Gy (including 20 Gy) had a significantly lower probability of pain recurrence when compared with those who received <20 Gy (HR, 0.36; 95% confidence interval, 0.14-0.94; P = .0365). There was no statistically significant difference in treatment response or pain recurrence between the different fraction numbers and sizes. However, we noted a trend indicating lower pain recurrence in the group that received 6 to 10 fractions of radiation therapy (P = .06). Among the most commonly used regimens, 8 Gy in a single fraction resulted in a statistically significant increased chance of pain recurrence compared with 20 Gy in 10 fractions and a borderline statistically significant increased chance of pain recurrence when compared with 30 Gy in 10 fractions.

CONCLUSIONS

Radiation therapy remains highly effective at managing lytic bone lesions in patients with MM, and 6- to 10-fraction treatment courses are equally as effective as longer courses at treating these lesions. Treatment with 20 Gy in 10 fractions resulted in a significantly lower probability of pain recurrence when compared with 8 Gy in 1 fraction.

Brain metastasis from squamous cell carcinoma of the head and neck: a review of the literature in the genomic era

Squamous cell carcinoma of the head and neck (HNSCC) affects nearly 500,000 individuals globally each year. With the rise of human papillomavirus (HPV) in the general population, clinicians are seeing a concomitant rise in HPV-related HNSCC. Notably, a hallmark of HPV-related HNSCC is a predilection for unique biological and clinical features, which portend a tendency for hematogenous metastasis to distant locations, such as the brain. Despite the classic belief that HNSCC is restricted to local spread via passive lymphatic drainage, brain metastases (BMs) are a rare complication that occurs in less than 1% of all HNSCC cases. Time between initial diagnosis of HNSCC and BM development can vary considerably. Some patients experience more than a decade of disease-free survival, whereas others present with definitive neurological symptoms that precede primary tumor detection. The authors systematically review the current literature on HNSCC BMs and discuss the current understanding of the effect of HPV status on the risk of developing BMs in the modern genomic era.

Use of Radiation in Extramedullary Leukemia/Chloroma: Guidelines From the International Lymphoma Radiation Oncology Group

Survival times for patients with leukemia generally have improved in recent decades, and this improvement has been attributed to an enhanced understanding of the genetics driving the cause of the disease and improved combinations of chemotherapy and targeted therapy. Durable control of systemic disease in blood and bone marrow has significantly improved survival, but extramedullary relapse can pose therapeutic challenges for which radiation therapy can have an important role. This report discusses the current role of radiation therapy for patients with leukemia, specifically the extramedullary manifestations of leukemia.

An In Vivo Murine Sciatic Nerve Model of Perineural Invasion

Cancer cells invade nerves through a process termed perineural invasion (PNI), in which cancer cells proliferate and migrate in the nerve microenvironment. This type of invasion is exhibited by a variety of cancer types, and very frequently is found in pancreatic cancer. The microscopic size of nerve fibers within mouse pancreas renders the study of PNI difficult in orthotopic murine models. Here, we describe a heterotopic in vivo model of PNI, where we inject syngeneic pancreatic cancer cell line Panc02-H7 into the murine sciatic nerve. In this model, sciatic nerves of anesthetized mice are exposed and injected with cancer cells. The cancer cells invade in the nerves proximally toward the spinal cord from the point of injection. The invaded sciatic nerves are then extracted and processed with OCT for frozen sectioning. H&E and immunofluorescence staining of these sections allow quantification of both the degree of invasion and changes in protein expression. This model can be applied to a variety of studies on PNI given its versatility. Using mice with different genetic modifications and/or different types of cancer cells allows for investigation of the cellular and molecular mechanisms of PNI and for different cancer types. Furthermore, the effects of therapeutic agents on nerve invasion can be studied by applying treatment to these mice.