Treatment Modality Impact on Patient-Reported Quality of Life in Human Papilloma Virus-Associated Oropharyngeal Carcinoma

OBJECTIVE

To prospectively compare the impact of treatment modality on patient-reported quality of life (QOL) in human papillomavirus-associated oropharynx squamous cell carcinoma (HPV + OPSCC).

STUDY DESIGN

Prospective cohort study.

SETTING

Academic medical center.

METHODS

One hundred one patients with American Joint Committee on Cancer (AJCC) 8th edition T1-3 N0-2 HPV + OPSCC completed the European Organization for Research and Treatment of Cancer Quality of Life Core questionnaire and Head and Neck Module pretreatment and 3-month and 1-year posttreatment. Mean score changes were compared to published minimal clinically important differences.

RESULTS

Patients underwent surgery alone (SA: N = 42, 42%), surgery with adjuvant radiation (S-RT: N = 10, 10%), surgery with adjuvant chemoradiation (S-CRT: N = 8, 8%), definitive radiation (RT: N = 11, 11%), or definitive chemoradiation (CRT: N = 30, 30%). SA, S-[C]RT, and [C]RT patients all reported clinically significant difficulty with sense of taste/smell persisting at 1 year. S-[C]RT and [C]RT patients reported statistically and clinically significant worse salivary dysfunction and problems with social eating at 1 year than SA. S-[C]RT patients reported statistically and clinically significant worse fatigue and head and neck pain compared to [C]RT and SA patients at 3 months, but normalized at 1 year. S-CRT compared to S-RT had statistically and clinically worse physical and role functioning and swallowing difficulties at 3 months but this difference was resolved by 1-year posttreatment.

CONCLUSION

HPV + OPSCC patients after SA report the lowest posttreatment QOL impact, whereas after S-CRT report the highest symptom burden. Careful selection for definitive surgery is important given the possibility of adjuvant CRT. Patients can experience persistent sense taste and smell difficulties at 1 year with all treatment modalities.

LEVEL OF EVIDENCE

3 Laryngoscope, 134:1687-1695, 2024.

Postoperative inpatient surgical complications following head and neck microvascular free tissue transfer

BACKGROUND

Complications following head and neck microvascular free tissue transfer (MFTT) are common. Less is known about when they occur.

METHOD

Retrospective study of patients with primary or recurrent head and neck cancer undergoing MFTT reconstruction at a tertiary care institution. MFTT reconstructions with inpatient postoperative complications were included. The Kruskal-Wallis test was used to compare median postoperative day (POD) onset of complication by flap type.

RESULTS

Of 1090 patients undergoing MFTT reconstruction, 126 (11.6%) patients experienced inpatient complications including fibula (n = 35), anterolateral thigh (n = 60), or radial forearm (n = 31) MFTTs. POD onset was shortest for surgical site hematoma (median = 1 [IQR 1-5]), and longest for donor site infection (median = 11.5 [IQR 8-15]). There was no significant difference between flap types and POD onset of complications (p > 0.05).

CONCLUSION

Hematoma formation and flap failure occur earliest during hospitalization, while dehiscence, infection, and fistula occur later. There is no difference in complication timing between flap types.

The Impact of Venous Anastomosis Technique on Outcomes of Free Tissue Transfer to the Head and Neck

Objectives: To evaluate the impact of different techniques of microvascular venous anastomosis on the outcome of free tissue transfer to the head and neck. Methods: Retrospective case series of patients undergoing microvascular free tissue transfer (MFTT) from January 2006 to September 2021. Chi-square tests and t-tests were utilized to identify differences in flap outcomes by technique, and log-binomial regression analyses were utilized to identify differences in flap outcomes by technique. Results: A total of 1055 consecutive MFTTs were analyzed. One hundred four cases required a return to the operating room for any reason, and 19 were attributed to venous compromise (18.0%). Ultimately, there were 22 FTT failures requiring complete revision (2.1%). In total, 1055 MFTTs involved 1352 venous anastomoses, ranging from 1 to 3 anastomoses in each case. End-to-end (ETE) was used 1040 times (76.9%) and end-to-side (ETS) 204 times (15.0%). The calculated risk ratio for venous complication for ETS compared with ETE was 1.17 (0.34-3.98). A microvascular coupler was used in 355 cases (33.6%). The calculated risk ratio for coupler compared with suture anastomoses was 0.92 (0.35-2.39). Conclusions: There were no significant difference in regard to outcomes of MFTT when comparing ETE with ETS, nor when comparing coupler with suture anastomoses.

Circulating tumor HPV DNA assessments after surgery for human papilloma virus-associated oropharynx carcinoma

PURPOSE

To understand the utility of circulating tumor human papillomavirus DNA (ctHPVDNA) blood testing for HPV-associated oropharynx squamous cell carcinoma (HPV + OPSCC) after definitive surgery.

MATERIALS AND METHODS

Prospective cohort study of HPV(+)OPSCC patients with ctHPVDNA test data to assess its accuracy in detecting biopsy-confirmed disease at various post-treatment time points. Eligible patients had p16(+)/HPV(+) OPSCC and ctHPVDNA testing performed at any time pre-operatively and/or postoperatively. In cases of recurrence, patients were excluded from analysis if ctHPVDNA testing was not performed within 6 months of biopsy.

RESULTS

196 all-treatment-type patients had at least one PT ctHPVDNA test. The initial post-treatment (PT) ctHPVDNA sensitivity, specificity, PPV, and NPV were 69.2 % (9/13), 96.7 % (177/183), 60.0 % (9/15), and 97.8 % (177/181). 61 surgery alone (SA) patients underwent 128 PT tests. The initial PT SA ctHPVDNA sensitivity, specificity, PPV, and NPV were 100 % (2/2), 96.0 % (48/50), 50 % (2/4), and 100 % (48/48). 35 of 61 (57.4 %) SA patients had NCCN-based histopathologic indications for adjuvant (chemo)radiation but declined. 3 of 35 (8.57 %) had a positive PT ctHPVDNA test of which 1 of 3 (33 %) had biopsy-proven recurrence. Prospectively, ten patients had a PreT positive ctHPVDNA, underwent SA, refused adjuvant treatment, had an undetectable ctHPVDNA within 2 weeks of SA, and remained free of disease (mean 10.3 months).

CONCLUSION

The high specificity and NPV of ctHPVDNA after SA suggest ctHPVDNA may have a role in determining the omission of PT adjuvant (chemo)radiation in select patients.

Prognostic risk factors of buccal squamous cell carcinoma: A case-control study

OBJECTIVES

To describe the clinicopathologic presentation of buccal squamous cell carcinoma and identify risks factors for recurrence and overall survival.

METHODS

This is a retrospective case-control study of patients with oral cavity squamous cell carcinoma (OCSCC) treated at a single tertiary care center between 2010 and 2022. All patients with buccal subsite OCSCC treated during this time frame were included and paired with a randomly selected age and gender matched patient with non-buccal OCSCC. Relevant data was collected via chart review.

RESULTS

Seventy-seven patients with buccal SCC were matched with 77 non-buccal OCSCC controls. The median follow-up time was 27 months (IQR 14-61). Median age was 67 years (IQR 57-75) and 53% of the cohort was female. Twenty (26%) buccal SCC patients experienced a recurrence versus 19 (25%) in the controls. Age ≥65-years-old increased odds of all-cause mortality in the buccal SCC group, but not in the control group. Perineural invasion and positive margins increased odds of recurrence in the buccal group only. Overall survival and progression-free survival did not differ between the groups, despite a greater number of T2 buccal tumors and T1 non-buccal tumors.

CONCLUSIONS

Buccal SCC presents at a higher T stage than other oral cavity SCC subsite and may exhibit variance in the pathologic risk factors that predict poor outcomes versus non-buccal OCSCC. Despite these relatively minor differences, however, oncologic outcomes between these groups were similar.

Increasing Pedicle Reach with Musculocutaneous Perforator Dissection in Anterolateral Thigh Free Flaps

OBJECTIVE

To measure the increase in effective pedicle reach with microdissection of musculocutaneous perforators during anterolateral thigh (ALT) free tissue harvest.

METHODS

A review of our institution's free flap database was performed to identify ALT free tissue transfers. The distance from pedicle vessel origin to its perforator's insertion at the fascia lata (effective pedicle length [EPL]) was measured prior to and following intramuscular dissection of musculocutaneous perforators. Pertinent clinicopathologic variables were abstracted from the electronic medical record.

RESULTS

A total of 314 ALT free flaps were performed between February 2017 and August 2022. Of these, 85 had documentation of EPL before and after musculocutaneous perforator dissection. ALT reconstruction was primarily performed for reconstruction of oncologic ablative defects (66, 78%). The mean EPL prior to perforator microdissection was 8.8 cm (standard deviation, SD 2.8 cm; range 3-15 cm). Following perforator dissection, mean EPL significantly increased to 14.0 cm (SD 3.0 cm; range 7-22 cm) with a mean net gain of 5.2 cm in distance (95% confidence interval 4.8-5.6 cm; p < 0.001). Nine patients (11%) required operating room take-back for anastomosis revision (3, 3.5%), recipient site hematoma evacuation (4, 4.7%), and wound dehiscence (2, 2.3%); one complete flap loss due to venous thrombosis was observed.

CONCLUSION

Dissection of musculocutaneous perforators during ALT free flap harvest can increase effective pedicle reach by 5.2 cm or nearly 60%. This harvest technique can facilitate the performance of tension-free anastomoses when substantial vascular pedicle length or vascular pedicle tunneling is required.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:666-670, 2024.

The neutrophil-to-lymphocyte ratio in salivary gland cancers treated with pembrolizumab

BACKGROUND

A minority of patients with recurrent/metastatic (R/M) salivary gland cancers (SGCs) benefit from immune checkpoint inhibitors (ICIs), necessitating reliable biomarkers for ICI response prediction.

METHODS

Retrospective observational study of R/M SGC patients treated with pembrolizumab between 2016 and 2022, with a primary outcome of 6-month progression-free survival (PFS) and secondary outcome of 2-year overall survival (OS). Univariate and multivariable Cox proportional hazards models were employed.

RESULTS

Twenty R/M SGC patients were included. After adjustment, NLR as a continuous variable was independently associated with 6-month PFS (HR 1.30, 95% CI 1.10-1.54, p = 0.002) and 2-year OS (HR 1.33, 95% CI 1.07-1.66, p = 0.010). Similarly, NLR ≥ 5 was associated with higher hazards of progression at 6 months (HR 12.85, 95% CI 2.17-76.16, p = 0.005) and death at 2 years (HR 11.25, 95% CI 1.67-75.77, p = 0.013).

CONCLUSIONS

Higher pretreatment NLR was independently associated with inferior 6-month PFS and 2-year OS in pembrolizumab-treated R/M SGC patients.

Outcomes Associated with Multiple Free Tissue Transfers Performed in a Single Day

Background: Although microvascular free tissue transfer (MFTT) remains technically challenging, surgeons may need to perform >1 MFTT operations in a given day. Objective: To compare MFTT outcomes in cases where surgeons completed one versus two flaps per day by measuring flap viability and complication rates. Methods: A retrospective review was conducted of MFTT cases from January 2011 to February 2022 with >30-day follow-up. Outcomes, including flap survival and operating room takeback, were compared using multivariate logistic regression analysis. Results: Of 1096 patients meeting inclusion criteria (1105 flaps), there was a male predominance (n = 721, 66%). Mean age was 63.0 ± 14.4 years. Complications requiring takeback were identified in 108 flaps (9.8%) and were greatest for double flaps in the same patient (SP) (27.8%, p = 0.06). Flap failure occurred in 23 (2.1%) cases and was also greatest for double flaps in the SP (16.7%, p = 0.001). Takeback (p = 0.06) and failure (p = 0.70) rates were not different between days with one versus two unique patient flaps. Conclusions: Among patients undergoing MFTT, those treated on days in which surgeons perform two unique cases compared with single cases will demonstrate no difference in outcomes, as measured by flap survival and takeback, whereas patients with defects requiring multiple flaps will experience greater takeback and failure rates.

A prospective evaluation of neck and shoulder function following treatments of early-stage human papillomavirus-associated oropharynx cancer

OBJECTIVES

To compare post-treatment neck and shoulder function between human papillomavirus-associated oropharynx squamous cell carcinoma (HPV + OPSCC) treatments.

DESIGN

Prospective, repeated-measures study.

SETTING

Tertiary care center.

PARTICIPANTS

Treatment-naïve patients with American Joint Committee on Cancer eighth edition stage T0-3/N0-2 HPV+OPSCC.

MAIN OUTCOME MEASURES

Patients completed the Neck Dissection Impairment Index (NDII) pre-treatment and 3-months and 1-year post-treatment. The NDII assesses 10 neck and shoulder functions scored 0-5 (total score 0-100), with higher scores suggesting better function.

RESULTS

A total of 106 patients underwent: surgery alone (SA, n = 46, 43%), surgery with adjuvant radiation ± chemotherapy (S + a[C]XRT, n = 18, 17%), or definitive radiation ± chemotherapy (d[C]XRT, n = 42, 40%). cTN classification and pre-treatment NDII scores did not differ between groups. SA patients reported worsened 3-month post-treatment versus pre-treatment self-care (4.6 vs. 5.0), lifting light (4.6 vs. 5.0) and heavy (4.2 vs. 4.8) objects, overhead reach (4.5 vs. 4.9), activity (4.5 vs. 4.9), socialization (4.7 vs. 4.9), recreation (4.6 vs. 4.9), and overall score (86.8 vs. 95.3) (all p < 0.05). One-year post-treatment scores (n = 34) were no different than pre-treatment in all domains. S + a[C]XRT patients reported worsened 3-month versus pre-treatment stiffness (4.0 vs. 4.8), lifting heavy objects (3.8 vs. 4.9), overhead reach (4.2 vs. 4.9), socialization (4.6 vs. 5.0), recreation (4.4 vs. 4.9) and overall score (82.4 vs. 96.0) (all p < 0.05). One-year post-treatment scores (n = 13) were no different than pre-treatment in all domains. d[C]XRT patients reported worsened 3-month versus pre-treatment difficulty lifting heavy objects (4.3 vs. 4.7) and recreation (4.3 vs. 4.7). One-year posttreatment scores (n = 21) were no different than pre-treatment in all domains.

CONCLUSION

HPV + OPSCC patients may experience mild shoulder/neck dysfunction 3 months after treatment that usually resolves by 1 year, independent of treatment modality.

Prospective quality of life outcomes for human papillomavirus associated oropharynx cancer patients after surgery alone

PURPOSE

To evaluate changes in patient-reported quality of life (QOL) to inform treatment decisions for human papillomavirus-associated oropharynx squamous cell carcinoma (HPV + OPSCC).

MATERIALS AND METHODS

Patients with American Joint Committee on Cancer (AJCC) 8th edition cT0-T3 and cN0-N3 HPV + OPSCC treated with transoral robotic surgery to the primary site with neck dissection completed questionnaires prior to surgery and at three-months and one-year post-operatively. Questionnaires included four validated instruments: the University of Washington Quality of Life Questionnaire (UW-QOL), European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) and Head and Neck Module (HN35), and the Neck Dissection Impairment Index (NDII).

RESULTS

Forty-eight patients filled out pretreatment and three-month questionnaires. 37 patients filled out one-year questionnaires. With the UW-QOL, at three-months, patients reported a statistically significant and clinically meaningful decreased mean score for appearance that resolved at one-year (presurgery: 92.4, 3-month: 81.0, p < 0.001; one year: 86.5). At three months and one-year, significant and clinically meaningful decreased mean taste scores persisted (presurgery: 98.0; three-months: 76.3, one-year: 80.3; all p < 0.001). With the EORTC QLQ-C30 and HN35, at one-year, only mean scores for sense of taste or smell (one-year: 13.1; p < 0.001) did not return to baseline. With the NDII, patients returned to functions comparable to baseline in all domains.

CONCLUSION

Post-treatment quality of life is high for HPV+ OPSCC patients treated with surgery alone. Mild taste and possibly smell dysfunction may continue in some patients. With careful selection, surgery alone for HPV + OPSCC offers favorable QOL outcomes.

LAY SUMMARY

Patients with HPV+ associated oropharynx cancer treated with surgery alone completed quality of life questionnaires before and after surgery. Quality of life remained high for most patients, with a subset of patients experiencing mild taste dysfunction one-year after surgery.

Restarting Therapeutic Antibiotics Following Postoperative Prophylaxis in Head and Neck Microvascular Free Tissue Transfer

OBJECTIVE

To determine factors associated with restarting therapeutic antibiotics within 30 days of head and neck microvascular free tissue transfer (HN-MFTT).

STUDY DESIGN

Retrospective study of consecutive HN-MFTTs performed from January 2015 to July 2020.

SETTING

Tertiary academic medical center.

METHODS

Thirty-day postoperative antibiotic use and post-HN-MFTT surgical and medical complications were assessed. Univariable analyses and multivariable logistic regression were used to evaluate risk factors associated with restarting antibiotics.

RESULTS

overall 482 patients with 501 HN-MFTTs were stratified by duration of prophylaxis: ≤24 hours (n = 136, 27.1%), 25-72 hours (n = 54, 10.8%), and >72 hours (n = 311, 62.1%). Antibiotics were restarted in 199 patients (209 procedures, 42%). The most common indications for antibiotic reinitiation were flap recipient site infection (n = 59, 28%); hospital-acquired pneumonia (n = 44, 21%); and wound dehiscence, fluctuance, or change in quality of drain output (n = 44, 21%). Shorter antibiotic prophylaxis (≤24 hours) (odds ratio [OR], 1.95; 95% CI, 1.2-3.0; P = .003), osteocutaneous flaps (OR, 2.15; 95% CI, 1.3-3.4; P = .001), and prior immunotherapy/chemotherapy (OR, 2.29; 95% CI, 1.2-4.3; P = .01) were associated with reinitiation of antibiotics for surgical infections. Restarting antimicrobials for nosocomial infections was associated with aerodigestive defects (OR, 2.45; 95% CI, 1.1-5.2; P = .019), cardiovascular disease (OR, 3.00; 95% CI, 1.5-5.9; P = .001), and medical comorbidities approximated by American Society of Anesthesiologists class 3 or 4 (OR, 2.83; 95% CI, 1.5-5.4; P = .002).

CONCLUSION

Aerodigestive reconstruction, 24-hour postoperative antimicrobial prophylaxis, American Society of Anesthesiologists class 3 and 4, prior chemotherapy/immunotherapy, cardiovascular disease, and osteocutaneous flaps are associated with reinitiation of antibiotics within 30 days of HN-MFTT.

Perioperative Topical Antisepsis and Surgical Site Infection in Patients Undergoing Upper Aerodigestive Tract Reconstruction

Importance

Surgical site infections (SSIs) after vascularized reconstruction of the upper aerodigestive tract (UADT) are associated with considerable morbidity. The association between perioperative prophylaxis practices, particularly topical antisepsis, and SSIs remains uncertain.

Objective

To assess the association between perioperative topical antisepsis and SSIs in patients undergoing vascularized reconstruction of the UADT.

Design, Setting, and Participants

This cohort study included patients from 12 academic tertiary care centers over an 11-month period, from July 1, 2020, to June 1, 2021. Patients undergoing open surgical procedures requiring a communication between the UADT and cervical skin with a planned regional pedicled flap, free flap, or both were included. Patients with an active infection at the time of surgical procedure were excluded.

Main Outcomes and Measures

The primary outcome measure was an SSI within 30 days of surgery. The association of demographic characteristics, perioperative antibiotic prophylaxis, surgical technique, and postoperative care with SSIs was assessed using univariable and multivariable analyses. The relative risk ratio and 95% CIs for developing SSI were calculated for each of the variables based on predetermined categories. Variables for which the relative risk 95% CI did not include the value of zero effect (relative risk = 1.00) were included in the multivariable model.

Results

A total of 554 patients (median age, 64 years; range, 21-95 years; 367 men [66.2%]) were included. Cancer ablation was the most frequent reason for surgery (n = 480 [86.6%]). Overall, the SSI rate was 20.9% (n = 116), with most infections involving the head and neck surgical site only (91 [78.4%]). The median time to SSI diagnosis was 11 days (range, 1-28 days). Topical antisepsis mucosal preparation was performed preoperatively in 35.2% (195) and postoperatively in 52.2% (289) of cases. Ampicillin and sulbactam was the most common systemic antibiotic prophylaxis agent used (n = 367 [66.2%]), with 24 hours being the most common duration (n = 363 [65.5%]). On multivariable analysis, preoperative topical antisepsis mucosal preparation (odds ratio [OR], 0.49; 95% CI, 0.30-0.77) and systemic prophylaxis with piperacillin and tazobactam (OR, 0.42; 95% CI, 0.21-0.84) were associated with a decreased risk of a postoperative SSI. The use of an osseous vascularized flap was associated with an increased risk of postoperative SSI (OR, 1.76; 95% CI, 1.13-2.75).

Conclusions and Relevance

Findings of this study suggest that preoperative topical antisepsis mucosal preparation was independently associated with a decreased risk of SSIs in a 12-center multi-institutional cohort. Further investigation of the association between individual perioperative practices and the incidence of postoperative SSIs is necessary to develop evidence-based protocols to reduce SSIs after UADT reconstruction.

Effect of microporous polysaccharide hemospheres on anterolateral thigh free flap donor site complications

Background

Postoperative seroma is the most common donor site complication following anterolateral thigh (ALT) free flap harvest for head and neck reconstruction. The utility of novel microporous polysaccharide hemospheres (MPH) has not been studied as a hemostatic agent in this setting.

Methods

Prospective, single‐blind, randomized controlled trial of patients undergoing fasciocutaneous ALT harvest for head and neck reconstruction at a tertiary academic medical center between April 2018 and February 2020. The intervention (MPH) group received 3 g of topical MPH to the ALT donor site prior to closure whereas the control group did not receive application of MPH. Outcomes included total drain output (ml), drain output during postoperative days (POD) 1–3 alone, drain duration (days), and incidence of donor site hematoma, seroma, or infection.

Results

Twenty‐nine patients were randomized to the MPH group and 26 to the control group. For MPH and control groups, mean total drain output was 284.7 ± 153.0 ml versus 317.9 ± 177.6 ml (p = .527), mean POD 1–3 drain output alone was 169.3 ± 88.8 ml versus 157.9 ± 78.7 ml (p = .749), and drain duration was 5.9 ± 1.5 days versus 6.5 ± 1.6 days (p = .144), respectively. There was no significant difference in seroma (p = .733), hematoma (p = .492), or infection (p = 1.000). Drain output was not significantly influenced by gender, age, body weight, or smoking habits.

Conclusion

MPH administration to ALT free flap donor sites did not significantly improve drain output, hematoma formation, or seroma formation.

Level of Evidence 2

Skin Color Match in Head and Neck Reconstructive Surgery

OBJECTIVES/HYPOTHESIS

To quantify the degree of color match achieved during microvascular facial reconstruction, and to describe a novel technique for improving reconstructive skin color match. We hypothesize that split-thickness skin grafts (STSG) placed atop de-epithelialized free tissue produces better facial skin color match than free tissue with intact epithelium.

STUDY DESIGN

Cross sectional photographic study of reconstructed facial skin color match.

METHODS

Sixty-eight adults, who underwent head and neck reconstructive surgery, were divided into six categories based on cutaneous reconstructive technique: cervicofacial flap, radial forearm free flap (RFFF), fibula free flap, anterolateral thigh free flap (ALT), STSG over adiopofascial flap (STAFF), and STSG over myogenous flap (STMF). Averaged color samplings of the reconstructed defect and adjacent normal skin were taken from digital photographs. The color difference was calculated using the delta-E calculation. Blinded expert observers also rated the degree of color match. Nonparametric cohort contrast and correlation statistical analyses were performed.

RESULTS

The mean delta-E's and 10-point Likert ratings for the ALT, fibula, RFFF, STAFF, STMF, and cervicofacial flaps were 11.6, 10.0, 7.7, 6.3, 8.8, and 4.7, and 5.1, 6.4, 2.4, 3.2, 2.7, and 1.1, respectively. Likert scale inter-rater correlation was strong, with coefficient = 0.80.

CONCLUSIONS

On average, STSG over de-epithelialized myogenous and adipofascial free tissue transfers produced a better color match than the skin paddles of donor sites, with the exception of the radial forearm donor site. Delta-E values obtained from photos correlated well with expert ratings of color match. This reliable technique for quantifying color match may be used in future studies.

LEVEL OF EVIDENCE

3 Laryngoscope, 2021.

Risk of Pathologic Extranodal Extension and Other Adverse Features After Transoral Robotic Surgery in Patients With HPV-Positive Oropharynx Cancer

Importance

Understanding patient-specific risk of adverse histopathologic findings after primary surgery for human papillomavirus (HPV)-positive oropharynx squamous cell carcinoma (OPSCC) may help guide patient consultations.

Objective

To determine the likelihood of adverse histopathologic features that may indicate adjuvant radiotherapy or chemoradiotherapy after primary surgery for HPV-positive OPSCC according to 2021 National Comprehensive Cancer Network guidelines.

Design, Setting, and Participants

This retrospective cohort study was performed at a single academic tertiary care center. Of 258 patients who underwent transoral robotic surgery (TORS) from March 1, 2012, to March 1, 2021, 136 consecutive, treatment-naive patients with HPV-positive OPSCC without obvious clinical extranodal extension (ENE) who underwent definitive TORS and neck dissection were included in the analysis. Indications for surgical treatment included non-deeply infiltrative oropharynx tumors, minimal soft palate involvement, and low suspicion for pathologic ENE.

Exposures

Primary site TORS with neck dissection.

Main Outcomes and Measures

The primary outcomes were the adverse histopathologic features of pathologic ENE and positive surgical margins (PSM) that are indications for possible adjuvant chemoradiotherapy. Outcomes were compared among varying American Joint Committee on Cancer 7th edition (AJCC-7) T and N categories and patient clinical characteristics.

Results

Of the 136 patients included in the analysis (113 men [83.1%]; median age, 63 [interquartile range, 55-70] years), 109 (80.1%) had at least 1 indication for possible adjuvant radiotherapy. Twenty-seven patients (19.9%) had pathologic ENE and 10 (7.3%) had PSM. Thirty-four patients (25.0%) had pathologic ENE and/or PSM, whereas 3 (2.2%) had both. Age, smoking history, history of alcohol consumption, and clinical T category were not associated with pathologic ENE, PSM, lymphovascular invasion, perineural invasion, or pN2 category or greater. The proportion of pathologic ENE varied by clinical N category: 0 of 16 for cN0, 8 of 48 (16.7%) for cN1, 3 of 23 (13.0%) for cN2a, and 16 of 45 (35.6%) for cN2b. Compared with patients with cN1-cN2a disease, patients with cN2b disease had higher odds of pathologic ENE (odds ratio, 3.01; 95% CI, 1.14-8.10). Clinical and pathologic N category were concordant in 77 patients (56.6%), whereas 42 (30.9%) were upstaged and 17 (12.5%) were downstaged.

Conclusions and Relevance

In this cohort study, approximately one-quarter of carefully selected patients with HPV-positive OPSCC without obvious clinical ENE undergoing primary surgery had pathologic ENE and/or PSM. Patients with AJCC-7 cT0-cT2 cN0-cN2b disease, especially cN0-cN2a, without signs of clinical ENE may represent appropriate candidates for primary surgery when avoidance of adjuvant chemotherapy and/or reduction of adjuvant radiotherapy dose/extent are the goals.

Utility of Microporous Polysaccharide Hemosphere on Anterolateral Thigh Free Flap Donor Site Complications

Background: Anterolateral thigh (ALT) microvascular free tissue transfer is an integral part of head and neck reconstructive surgery, but it can be complicated by postoperative donor site fluid collections. Objective: To measure the rate of hematoma and seroma formation in the ALT donor site in those treated with microporous polysaccharide hemosphere (MPH) and those without. Methods: This was a retrospective cohort study examining patients undergoing ALT free tissue transfer for head and neck reconstruction at a single academic center between 2014 and 2017. Primary outcomes were interventional hematomas and seromas and drain duration. Results: In total, 118 patients underwent ALT free flap reconstruction for head and neck defects. Of these, 57 patients received MPH at the donor site and 61 did not. Eleven patients had a clinically significant seroma in the non-MPH group compared with three in the MPH group (p = 0.045). Drain duration for the MPH group compared with that for the non-MPH group was 6.9 versus 8.2 days (p = 0.020), and drains were removed when output was <60 mL over 24 h. Conclusion: This study supports the use of MPH in ALT free flap donor sites for reduction of clinically significant postoperative seromas. Further investigation with larger prospective randomized clinical trials is warranted.

Hepatitis C as a Potential Risk Factor for Adverse Surgical Outcomes in Head and Neck Free Tissue Transfer Reconstruction

Background: Infection with hepatitis C virus (HCV) is associated with an increased risk of developing head and neck cancer (HNC), and negatively impacts cancer-specific survival. Objective: To measure the impact of HCV status on free tissue transfer failure, flap takeback, and length of stay in HNC patients undergoing reconstruction. Methods: We retrospectively reviewed patients who underwent head and neck free tissue transfer reconstruction at a single academic institution between August 2011 and June 2020. Results: In the HCV-infected group, total flap failure rate was 2.9% versus 1.3% in the control group and the takeback rate was 11.1% versus 9.6%. On multivariate analysis, HCV status was not associated with flap failure, flap takeback, or total length of hospital stay >7 days. Conclusion: In this study, HCV status was not associated with differences in postoperative complications or length of stay. Future research with greater numbers of HCV-positive study subjects is required to elucidate the effect of HCV infection in this patient population.

A prospective study of patient-reported xerostomia-related outcomes after parotidectomy

OBJECTIVE

There is a paucity of data on patient-reported outcome measures regarding xerostomia after parotidectomy surgery. Although salivary flow rates after parotidectomy have been previously studied, they do not correlate with subjective xerostomia. This study was designed to evaluate if unilateral parotidectomy increases patient-reported xerostomia.

METHODS

A prospective cohort of patients undergoing unilateral partial, superficial, or total parotidectomy for benign or low-grade malignant pathology without postoperative radiation at a tertiary care academic center was studied. We analyzed patient-reported outcome measures of xerostomia using the Xerostomia Questionnaire (XQ) preoperatively and postoperatively. We compared pre- and postoperative cumulative and individual XQ scores using Wilcoxon signed-rank tests. We stratified patients by the weight in grams (g) of the parotid tissue excised, pathology, smoking status, and xerostomia-related medication use.

RESULTS

Twenty-two adults with benign or low grade malignant unilateral parotid tumors were included. Postoperative questionnaires were completed at a median of 10.2 months (interquartile range [IQR] 8.6-11.9) after unilateral parotidectomy. Mean preoperative and postoperative cumulative XQ scores, on a 100-point scale, with higher scores representing worse symptoms, were 10.33 (95% CI: 4.46-16.20) and 10.54 (95% CI: 5.10-15.98), respectively, with a mean change of +0.21 (p = 0.472). There were no statistically significant changes in individual XQ symptom scores. Neither type of parotidectomy, resection specimens weighing over 10 g, smoking habits, xerostomia-related medication use, nor malignant pathology were associated with worse symptom scores.

CONCLUSION

Based on these data, unilateral parotidectomy does not appear to definitely, or at least consistently, increase xerostomia per patient reporting. More extensive parotid resections are not associated with worse symptom scores. These data can help guide preoperative counseling and postoperative expectations for parotidectomy.

LEVEL OF EVIDENCE

2b.

Patient-Reported Aesthetic and Psychosocial Outcomes After Microvascular Reconstruction for Head and Neck Cancer

Importance

Aesthetic outcomes are key determinants of psychosocial functioning among surgically treated patients with head and neck cancer (HNC); however, long-term aesthetic outcomes after microvascular free tissue transfer (MFTT) are not well described.

Objective

To examine risk factors for impaired long-term aesthetic satisfaction and appearance-related psychosocial functioning after HNC ablation with MFTT.

Design, Setting, and Participants

A cross-sectional, web-based survey was conducted at an academic tertiary care center. A total of 228 individuals who underwent MFTT between January 1, 2015, and December 31, 2019, for treatment of HNC were included. The study was conducted from November 1, 2020, through January 15, 2021.

Exposures

Head and neck cancer ablation with MFTT.

Main Outcomes and Measures

Patient-reported outcomes were assessed via Aesthetic FACE-Q scales. The primary objective was aesthetic satisfaction determined by the Satisfaction With Facial Appearance scale. Secondarily, the Appearance-Related Psychosocial Distress, Psychological Function, and Social Function scales were used to assess appearance-related psychosocial functioning. Patients were stratified by demographic, disease, surgical, and postoperative characteristics. Survey scores on a 100-point scale were compared and subjected to univariable and multivariable linear regression.

Results

A total of 124 of 228 patients (54.4%) completed surveys a median of 34.4 months after MFTT (interquartile range, 22.6-48.8). Most responders (79 [63.7%]) were men with advanced cancer of the oral cavity or skin, reconstructed with anterolateral thigh or osteocutaneous fibula free flaps. Nonresponders had no significant differences in baseline characteristics. The Satisfaction With Facial Appearance score was independently lower among patients who received osteocutaneous flaps (regression coefficient, -10.6 points, 95% CI, -20.4 to -0.8 points) and/or adjuvant (chemo)radiotherapy (regression coefficient, -6.9 points; 95% CI, -13.8 to -0.1 points). Impaired appearance-related psychosocial functioning was independently associated with female sex, a history of anxiety or depression, osteocutaneous flaps, prolonged tube feeding requirements, and any recurrent or persistent disease. After adjustment for covariates, each 1-point increase in the Satisfaction With Facial Appearance score independently estimated improved appearance-related psychosocial functioning as determined by the Appearance-Related Psychosocial Distress scale (regression coefficient, -0.5 points; 95% CI, -0.7 to -0.4 points), Psychological Function scale (regression coefficient, 0.4 points; 95% CI, 0.3 to 0.5 points), and Social Function scale (regression coefficient, 0.4 points; 95% CI, 0.3 to 0.6 points).

Conclusions and Relevance

The findings of this cross-sectional, web-based survey study suggest that osteocutaneous reconstruction and adjuvant therapy independently increase the risk of poor patient-reported long-term aesthetic satisfaction, which correlated with impaired appearance-related psychosocial functioning. Aesthetic outcomes appear to be a priority to address in patients with HNC undergoing MFTT.

Impact of Smoking and Primary Tumor Subsite on Recurrence in HPV-Associated Oropharyngeal Squamous Cell Carcinoma

OBJECTIVE

To describe risk of recurrence and recurrence characteristics between ever- and never-smoking patients with human papillomavirus-associated oropharyngeal squamous cell carcinoma (HPV+ OPSCC) when stratified by primary tumor subsite.

STUDY DESIGN

Retrospective observational study.

SETTING

Tertiary care center.

METHODS

Retrospective chart review of 171 patients with HPV+ OPSCC with primary treatment between 2008 and 2019. Five-year recurrence-free survival and risk of recurrence were evaluated through Kaplan-Meier curves with log-rank test and Cox proportional hazards models, respectively.

RESULTS

Of 171 patients with HPV+ OPSCC, 81.9% were male, and the average age was 63.9 years. Eighty patients (46.8%) had a smoking history (average, 17.7 pack-years), including 4 current smokers. Recurrence occurred in 31 patients (18.1%), 19 of whom were ever smokers. The recurrence rate for ever smokers with primary base of tongue (BOT) cancer was 41.7%, while 5.1% of never smokers with BOT primaries had recurrence. For primary tonsillar disease, 9.1% of ever smokers had recurrence versus 19.2% of never smokers. Five-year recurrence-free survival for BOT primaries was lower in ever smokers than never smokers (P = .001) but did not differ between ever and never smokers for tonsillar primaries (P = .215). In multivariable analysis across this period, ever-smoking status was associated with higher risk of recurrence than never-smoking status in BOT primaries (adjusted hazard ratio, 7.36; 95% CI, 1.61-33.68; P = .010) but with lower risk of recurrence after tonsillar primaries (adjusted hazard ratio, 0.23; 95% CI, 0.06-0.89; P = .033).

CONCLUSION

Smoking may uniquely interact with tumor subsites within the oropharynx to influence recurrence risk. Understanding the association between smoking and HPV+ OPSCC recurrence could lead to personalized, evidence-based treatments to improve oncologic outcomes.

Nasogastric tube feeding after transoral robotic surgery for oropharynx carcinoma

PURPOSE

To determine the need for and predictors of nasogastric tube feeding (NGTF) use and duration after transoral robotic surgery (TORS) for oropharynx squamous cell carcinoma (OPSCC).

MATERIALS AND METHODS

This is a retrospective cohort study. For 95 OPSCC patients undergoing TORS with or without concurrent unilateral or bilateral neck dissections (ND), we evaluated NGTF use and duration, along with demographic, clinical, histopathologic, and treatment risk factors.

RESULTS

23.2% (22/95) of patients received NGTF. Univariate analysis found that NGTF was significantly more likely in larger tumor specimens (mean: 2.32 cm vs. 1.84 cm; p = 0.043) and after concurrent bilateral (46.7%) compared to unilateral (17.4%) ND (p = 0.043). Multivariable analysis also found increased tumor size (p = 0.035) and concurrent bilateral ND (p = 0.04) to be significant risk factors for NGTF. The following were not statistically significantly associated with NGTF use: sex, age, smoking history, HPV status, base of tongue (BOT) resection (20%) vs. radical tonsillectomy (25.9%), pT2 (27.0%) vs. pT1 (20.4%) vs pT0 (16.7%), BOT with (28.6%) vs. without epiglottis resection (22.2%), and surgery for additional margins the same day (27.3%) (all p > 0.1). Patients who underwent NGTF had a mean duration of 18 days (2-96, SD: 20.7 days) with 12 (55.6%) having over 2 weeks of use. No significant predictors of longer duration of NGTF were identified.

CONCLUSIONS

A majority of patients undergoing TORS do not need NGTF. When NGTF is needed, the duration of use is usually longer than 14 days. Larger tumor size and concurrent bilateral ND are risk factors for NGTF.

Patient-Reported Outcomes of Split-Thickness Skin Grafts for Floor of Mouth Cancer Reconstruction

INTRODUCTION

Patient-reported outcome measures (PROM) on quality of life (QOL) for early-stage floor of mouth carcinoma (FOM-CA) undergoing surgical resection and split-thickness skin graft (STSG) reconstruction have not been established. We have performed a cross-sectional QOL analysis of such patients to define functional postoperative outcomes.

METHODS

Patients with pathologic stage T1/T2 FOM-CA who underwent resection and STSG reconstruction at a tertiary academic cancer center reported outcomes with the University of Washington QOL (v4) questionnaire after at least 6 months since surgery.

RESULTS

Twenty-four out of 49 eligible patients completed questionnaires with a mean follow-up of 41 months (range: 6-88). Subsites of tumor involvement/resection included the following: (1) lateral FOM (L-FOM) (n = 17), (2) anterior FOM (A-FOM) (n = 4), and (3) alveolar ridge with FOM, all of whom underwent lateral marginal mandibulectomy (MM-FOM) (n = 3). All patients reported swallowing scores of 70 ("I cannot swallow certain solid foods") or better. Ninety-six percent (23/24) reported speech of 70 ("difficulty saying some words, but I can be understood over the phone") or better. A-FOM patients reported worse chewing than L-FOM patients (mean: 50.0 vs. 85.3; p = 0.01). All 4 A-FOM patients reported a low chewing score of 50 ("I can eat soft solids but cannot chew some foods"). Otherwise, there were no significant differences between subsite groups in swallowing, speech, or taste.

CONCLUSION

STSG reconstructions for pathologic T1-T2 FOM-CA appear to result in acceptable PROM QOL outcomes with the exception of A-FOM tumors having worse chewing outcomes.

Risk Factors for and Cost Implications of Free Flap Take-backs: A Single Institution Review

OBJECTIVE/HYPOTHESIS

For patients undergoing microvascular free tissue transfer (MFTT), we evaluated risk factors and financial implications of operating room (OR) take-back procedures.

STUDY DESIGN

Retrospective review at a tertiary care center.

METHODS

Patients who underwent MFTT for head and neck reconstruction from 2011 to 2018 were identified. We compared hospital length of stay and overall costs associated with OR take-back procedures. Multivariable regression analysis evaluated factors associated with OR take-backs during the same hospitalization.

RESULTS

A total of 727 free flaps were reviewed, and 70 OR take-backs (9.6%) were identified. Mean total length of stay (LOS) in the ICU was 3.4 days versus 6.7 days for non-take-back and take-back flaps, respectively (P < .001). Mean total LOS on the regular floor was 6.3 days versus 13.1 days, respectively (P < .001). This resulted in a cost differential of $33,507 (94.3% increase relative to non-take-back flaps). The total cost associated with an OR take-back was $39,786. Hematomas were the most common cause of take-backs and wound dehiscence was associated with the highest costs. On multivariable analysis, higher ASA class (OR, 2.06; 95% CI, 1.11-3.99; P = .026) and shorter ischemia times (OR, 0.52; 95% CI, 0.29-0.95; P = .030) were independently associated with increased risk of take-backs.

CONCLUSIONS

OR take-backs infrequently occur but are associated with a significant increase in financial burden when compared to free flap cases not requiring OR take-back. The large majority of the cost differential lies in a substantial increase of ICU and floor LOS for take-back flaps when compared to non-take-back flaps.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E1821-E1829, 2021.

Head and neck surgery during the coronavirus-19 pandemic: The University of California San Francisco experience

BACKGROUND

Guidelines regarding head and neck surgical care have evolved during the coronavirus-19 (COVID-19) pandemic. Data on operative management have been limited.

METHODS

We compared two cohorts of patients undergoing head and neck or reconstructive surgery between March 16, 2019 and April 16, 2019 (pre-COVID-19) and March 16, 2020 and April 16, 2020 (COVID-19) at an academic center. Perioperative, intraoperative, and postoperative outcomes were recorded.

RESULTS

There were 63 operations during COVID-19 and 84 operations during pre-COVID-19. During COVID-19, a smaller proportion of patients had benign pathology (12% vs 20%, respectively) and underwent thyroid procedures (2% vs 23%) while a greater proportion of patients underwent microvascular reconstruction±ablation (24% vs 12%,). Operative times increased, especially among patients undergoing microvascular reconstruction±ablation (687 ± 112 vs 596 ± 91 minutes, P = .04). Complication rates and length of stay were similar.

CONCLUSIONS

During COVID-19, perioperative outcomes were similar, operative time increased, and there were no recorded transmissions to staff or patients. Continued surgical management of head and neck cancer patients can be provided safely.

Vasodilation by Verapamil-Nitroglycerin Solution in Microvascular Surgery

OBJECTIVE

Papaverine is a topical vasodilator commonly used during microvascular surgery to inhibit undesired vasoconstriction. A previous national shortage of papaverine prompted evaluation of an alternative, effective vasodilator. This study aims to assess the experience of a solution of verapamil and nitroglycerin (VG) as a potential alternative pharmacologic vasodilator.

STUDY DESIGN

Retrospective case series.

SETTING

Two tertiary academic medical centers.

SUBJECTS AND METHODS

Among 298 patients, 306 consecutive free tissue transfers performed between 2014 and 2017 for head and neck defect reconstruction utilized a VG solution. Patient and flap characteristics, intraoperative patient and flap complications, and postoperative complications were reviewed. Diameter of the cervical recipient artery was measured intraoperatively before and after topical application of the VG solution in a subset of 43 patients (44 flaps).

RESULTS

Flaps included fibula, radial forearm, subscapular system, and anterolateral thigh. In total, 3 (0.98%) flaps failed with varied etiology unrelated to the VG solution (venous thrombosis, arterial anastomosis thrombosis, physical damage to the perforator). Specific to topical application of the VG solution, the mean recipient artery diameter increased from 2.1 to 3.1 mm, a 48% increase (P < .01). There were no intraoperative cardiac events or complications attributable to the VG solution.

CONCLUSION

We describe the use of a VG solution for pharmacologic vasodilation during microvascular free tissue transfer. Its use was associated with an acceptable incidence of adverse events, none of which were directly attributable to the VG solution. Apparent and sustained vasodilation was demonstrated. The VG solution represents a safe and efficacious alternative to papaverine in microvascular surgery.

Is It Worth It? Consequences of Definitive Head and Neck Reirradiation

Locally recurrent head and neck malignancies after definitive radiation or chemoradiation represent challenging clinical scenarios requiring careful consideration of individualized risks and benefits before deciding upon the next best course of therapy. Herein, a case-based approach to personalized decision making highlights the expert opinions of leaders in head and neck oncology. Topics of interest include optimal candidacy for reirradiation or salvage surgical resection, the judicious use of chemotherapy as induction therapy or as a radiosensitizing agent, the incorporation of immunotherapy into the treatment paradigm for locally recurrent disease, and the impact of various treatment modalities on quality of life and functional outcomes. Interestingly, the lack of consensus among the experts on topics as fundamental as the appropriateness of offering reirradiation at all and as nuanced as target volume delineation for the reirradiated field suggests that there is no straightforward approach in this scenario. Common to all opinions is a desire to maximize the therapeutic ratio for a patient potentially facing a grim prognosis, and honest discussions about goals of care and expectations for post-treatment quality of life should be central to the clinical approach to this and similar cases.

Modified technique of submandibular gland transfer followed by intensity modulated radiotherapy to reduce xerostomia in head and neck cancer patients

BACKGROUND

Xerostomia is one of the most common long-term adverse effects of radiotherapy for head and neck cancer patients. Contralateral submandibular gland transfer (SMG-T) before radiotherapy was shown to reduce xerostomia compared to pilocarpine. We sought to evaluate a modification of this surgery preserving the ipsilateral facial artery and vein to simplify the SMG-T.

METHODS

Eighteen patients planned for head and neck intensity modulated radiotherapy to both necks were reviewed. Surgical complications were recorded. The grade of xerostomia was assessed after treatment completion.

RESULTS

There were no minor or major complications resulting from the modified SMG-T. At 24.5-months follow up, the incidence of post-treatment moderate to severe xerostomia was 16.7%. No locoregional recurrence occurred. Only one patient had distant solitary lung metastasis.

CONCLUSION

The modified SMG-T technique is a practical and effective method to reduce the dose of radiation to the contralateral SMG and limit post-treatment xerostomia.

Improved Tumor Control Related to Radiotherapy Technological Development for Hypopharyngeal Cancer

OBJECTIVES/HYPOTHESIS

Squamous cell carcinoma of the hypopharynx (SCCHP) is associated with worse survival compared to other head and neck subsites. This report quantifies the impact of technological improvements in radiotherapy (RT) on outcomes over 6 decades.

METHODS

Patients with SCCHP receiving curative-intent treatment between 1962 and 2015 were retrospectively reviewed. Kaplan-Meier analyses of freedom from local recurrence (FFLR), progression-free survival (PFS), and overall survival (OS) were compared across treatment eras and radiation techniques. Multivariable Cox proportional hazards modeling was performed to specify the effect of RT technique.

RESULTS

One hundred thirty-four patients had a median follow-up of 17 months (IQR = 9-38). There were no differences in staging or use of surgery over time, but use of chemotherapy concurrent with RT increased (P < .001) beginning in the 2000s. The 24-month FFLR using two-dimensional RT (2D-RT), three-dimensional conformal RT (3D-CRT), and intensity-modulated RT (IMRT) was 52%, 55%, and 80%, respectively; 24-month PFS was 39%, 46%, and 73%, respectively; and 24-month OS was 27%, 40%, and 68%, respectively. OS (P = .01), PFS (P = .03), and FFLR (P = 0.02) were improved with IMRT over 2D-RT, and FFLR appeared to be improved over 3D-CRT (P = .06). Controlling for chemotherapy use and other major variables, IMRT produced a strong influence over FFLR (adjusted hazard ratio [HR] = 0.2, 95% confidence interval [CI]: 0.0-1.2, P = .08) and a benefit in OS (adjusted HR = 0.1, 95% CI: 0.0-0.4, P = .005).

CONCLUSIONS

Across 6 decades, patient and tumor characteristics remained similar whereas use of chemoradiation increased and IMRT was adopted. The introduction of IMRT was associated with improved FFLR, PFS, and OS, and a reduction in acute toxicity as compared to earlier radiation technologies.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E452-E458, 2021.

Patient-Reported Quality of Life After Resection With Primary Closure for Oral Tongue Carcinoma

OBJECTIVES/HYPOTHESIS

For early-stage oral tongue carcinoma and carcinoma in situ (ESOTCCIS), we evaluated patient-reported quality-of-life (QOL) outcomes following resection with primary closure (R-PC).

STUDY DESIGN

Retrospective review at an academic cancer center.

METHODS

Thirty-nine ESOTCCIS patients (Tis, T1, T2) who underwent R-PC without radiation completed the University of Washington Quality of Life Questionnaire Version 4 (UW-QOL) at least 6 months since R-PC (mean = 2.39 years; range = 0.5-6.7 years). We compared UW-QOL scores for pain, swallowing, chewing, speech, and taste to established normative population scores. Multivariable regression analysis evaluated factors associated with QOL impairment.

RESULTS

ESOTCCIS patients who underwent R-PC in comparison to the normative population reported significantly worse mean speech (87.7 vs. 98, P < .001) and taste (85.6 vs. 95, P = .002) scores and no significant differences in mean pain (91.7 vs. 86, P = .96), swallowing (100 vs. 98, P = .98), chewing (97.4 vs. 94, P = .98) scores. For speech and taste, 59% (23/39) reported no postoperative change from baseline, whereas 41% (16/39) and 35.9% (14/39) reported mild impairment, respectively. Overall, postoperative QOL was reported as good, very good, or outstanding by 87.2% (34/39). Higher American Society of Anesthesiologists class, cT1 compared to CIS, and ventral tongue involvement were independently associated with worse speech. Age < 60 years was independently associated with worse taste.

CONCLUSIONS

ESOTCCIS patients who undergo R-PC without radiation can expect long-term swallowing, chewing, and pain to be in the normative range. Although a majority of patients can expect to achieve normative speech and taste outcomes, R-PC carries the risks of mild speech and/or taste impairments.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:312-318, 2021.

Long-Term Stability of Vascularized Adipofascial Flaps in Facial Reconstruction

Objectives: To determine the quantitative volume change over time of vascularized adipofascial anterolateral thigh (AFALT) free flaps in facial reconstruction, and to evaluate patient factors that are associated with changes in volume. Methods: A retrospective review was performed on patients who underwent AFALT reconstruction for large volume parotid and midface defects after head and neck cancer surgery at a single tertiary care hospital from 2011 to 2018. Flap volume was measured at different time points using 3D Slicer, a free open source software for medical image computing. Trends in volume change over time were evaluated. A multiple linear regression model was used to analyze patient factors associated with mean final volume change. Results: Twenty-one patients were included. The median follow-up period from surgery was 17 months (interquartile range [IQR] = 9-25 months). The first imaging study was obtained a median of 3 months after surgery (IQR = 1-4 months). The majority of patients underwent postoperative radiation (20/21, 95%). Mean final total volume percentage change over time was 96.6% (standard deviation = 21.7%). After controlling for age, smoking history, recurrence, and length of follow-up, a reduction in body mass index (BMI) ≥1.5 U from baseline had the greatest association with mean final volume percentage change (β -31, 95% confidence interval: -52 to -11, p = 0.005). Conclusions: Free tissue transfer using AFALT flaps in the head and neck provided relatively stable volume maintenance over time, even after postoperative radiation. The volume of transplanted fat can change depending on patient factors, such as BMI.

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.

Patterns of care and survival impact of adjuvant chemoradiotherapy for oropharyngeal cancer with intermediate-risk features

BACKGROUND

Survival outcomes for adjuvant chemoradiotherapy (aCRT) and adjuvant radiotherapy (aRT) were compared in patients with oropharyngeal squamous cell carcinoma (OPSCC) with intermediate-risk features.

METHODS

We identified 2164 patients with OPSCC in the National Cancer Database without positive margins or extracapsular extension and with at least one intermediate-risk feature: pT3-T4 disease, ≥two positive lymph nodes, level IV/V nodal disease, and/or lymphovascular invasion. We assessed predictors of aCRT use and covariables impacting overall survival.

RESULTS

aCRT was commonly used for both human papillomavirus (HPV)-positive (62.0%) and HPV-negative (64.3%) patients with OPSCC. Higher N stage, level IV/V neck disease, and younger age strongly predicted aCRT utilization. There was no significant survival benefit associated with aCRT vs aRT in HPV-positive (hazard ratio [HR], 0.93; 95% confidence interval [CI], 0.62-1.38; P = .71) or HPV-negative (HR, 0.75; 95% CI, 0.51-1.10; P = .15) disease.

CONCLUSIONS

Despite high rates of utilization, aCRT is not associated with better survival vs aRT for OPSCC with intermediate-risk features, including HPV-negative tumors.

Socioeconomic disparities in a population of patients undergoing total thyroidectomy for benign disease

BACKGROUND

This study examines the effect of insurance status (as a measure of socioeconomic status) on patient with benign thyroid disease.

METHODS

A retrospective review was performed among 60 patients undergoing total thyroidectomy for benign thyroid disease. Univariate and multivariable analyses examined the relationship between insurance status and thyroid volume (sum of the left and right lobe volumes).

RESULTS

Twenty-eight (47%) patients were considered of underinsured/uninsured status, and 32 (53%) patients were considered of private/government/military insurance status. Median pathologic whole thyroid volume was 66 mL (range, 2-855). After multivariable linear regression, underinsured/uninsured status was the only significant predictor of larger volume (correlation coefficient [r] = 118; 95% CI, 42 to 194; P = .003), after adjusting for age, sex, body mass index, and presence of concomitant thyroid disease and compressive symptoms.

CONCLUSION

Patients of underinsured/uninsured status suffered more severe disease presentations at time of thyroidectomy, as measured by larger thyroid volumes.

Human Papillomavirus–Associated Oropharyngeal Cancer: Patterns of Nodal Disease

Objective

To characterize patterns of neck lymph node (LN) metastases in human papillomavirus (HPV)–associated oropharyngeal squamous cell carcinoma, represented by p16 positivity (p16+OPSCC).

Study Design

Case series with chart review.

Setting

Tertiary care center.

Subjects and Methods

Neck dissection (ND) specimens of nonirradiated p16+OPSCC patients were analyzed for frequencies of clinically evident and occult LNs by neck level. Local, regional, and distant recurrences were reviewed.

Results

Seventy p16+OPSCC patients underwent primary site transoral robotic surgery and 82 NDs of varying levels. Metastatic pathologic LNs were found at the following frequencies: 0% (0/28) in level I, 75.6% (62/82) in level II with 57.4% (35/61) in level IIA and 13.1% (8/61) in level IIB, 22.0% (18/82) in level III, 7.0% (5/71) in level IV, and 6.3% (1/16) in level V. The level V LN was clinically evident preoperatively. Five of 21 (23.8%) elective NDs contained occult LNs, all of which were in level II and without extranodal extension. Twenty-seven (38.6%) patients underwent adjuvant radiation; 19 (27.1%) patients underwent adjuvant chemoradiation. With a mean follow-up of 29 months, 3 patients had developed recurrences, with all but 1 patient still alive. All patients who recurred had refused at least a component of indicated adjuvant treatment.

Conclusions

For p16+OPSCC, therapeutic NDs should encompass any levels bearing suspicious LNs and levels IIA-B, III, and IV, while elective NDs should be performed and encompass at least levels IIA-B and III. These selective ND plans, followed by indicated adjuvant treatment, are associated with a low nodal recurrence rate.

Shorter interval between radiation therapy and salvage laryngopharyngeal surgery increases complication rates following microvascular free tissue transfer

PURPOSE

To evaluate how the interval between radiation and salvage surgery for advanced laryngeal cancer with free tissue transfer reconstruction influences complication rates.

MATERIALS AND METHODS

This is a retrospective series of 26 patients who underwent salvage laryngectomy or laryngopharyngectomy with vascularized free tissue reconstruction (anterolateral thigh or radial forearm) following radiation or chemoradiation between 2012 and 2017 at a single academic center. The primary outcome was incidence of postoperative complications, including pharyngocutaneous fistula. Secondary outcomes included the need for a second procedure, time to resumption of oral feeding, feeding tube dependence, and hospital length of stay.

RESULTS

Salvage surgery was performed for persistence (7/26, 27%), recurrence/new primary (12/26, 46%), and dysfunctional larynges (7/26, 27%). Twenty-two (85%) defects were reconstructed with an anterolateral thigh free flap and 4/26 with a radial forearm free flap (15%). There were no flap failures. There were significantly more complications in patients undergoing surgery within 12 months of completion of radiation therapy (7/12, 58%) versus those undergoing surgery after 12 months (1/14, 7%; p = .02). Patients experiencing complications more often required a second procedure (4/7 vs. 0/1; p = .02), experienced a longer delay to initiation of oral diet (61 vs. 21 days; p = .04), and stayed in the hospital longer (28 vs. 9 days; p = .01).

CONCLUSIONS

Shorter intervals between definitive radiation and salvage laryngopharyngeal surgery with free tissue reconstruction increases postoperative complications, hospital length of stay, and the likelihood of feeding tube dependence. Reconstructive surgeons can use these findings to help guide preoperative patient counseling and assess postoperative risk.

Squamous Cell Carcinoma of the Soft Palate in the United States: A Population-Based Study

Objectives To describe the incidence and determinants of survival of patients with squamous cell carcinoma of the soft palate (SCCSP) using the Surveillance, Epidemiology, and End Results (SEER) database. Study Design Retrospective, population-based cohort study of patients. Setting SEER cancer registry. Subjects and Methods Patients from the SEER cancer registry from 1973 to 2015 were used to analyze demographics and survival of SCCSP. Results A total of 4366 cases were identified. The average overall survival (OS) and disease-specific survival (DSS) were 68.7 months and 161.3 months, respectively. Multivariate analysis revealed that male sex, stage, and treatment (hazard ratio [HR] = 0.690, P = .019; HR = 1.73, P < .001; HR = 0.64, P < .001, respectively) were independent determinants of better or worse DSS. Age, stage, and treatment (HR = 1.02, P < .001; HR = 1.49, P < .001; HR = 0.66, P < .001; HR = 0.48, P < .001, respectively) were independent determinants of better or worse OS. For stages I, II, and III, radiation alone and surgery alone have nearly equivalent OS. Patients with stage IV disease who underwent both surgery and radiation had a significantly higher median OS at 50.0 months. Conclusion Radiation alone and surgery alone both have nearly equivalent OS benefit for stages I to III, while surgery and radiation provide the most survival benefit for stage IV disease. The large discrepancy between OS and DSS can be due to significant comorbidities. Future studies should aim to address the determinants of quality-of-life variables that help direct treatment decisions and might indirectly affect survival.

Submandibular Gland Transfer: A Potential Imaging Pitfall

BACKGROUND AND PURPOSE

The Seikaly and Jha submandibular gland transfer surgery is performed to facilitate gland shielding during radiation therapy for head and neck tumors to circumvent radiation-induced xerostomia. It results in an asymmetric postsurgical appearance of the submandibular and submental spaces. Our purpose was to characterize the morphologic and enhancement characteristics of the transferred submandibular gland and identify potential pitfalls in postoperative radiologic interpretation.

MATERIALS AND METHODS

This retrospective study identified patients with head and neck cancer who had undergone the submandibular gland transfer procedure at our institution. Chart reviews were performed to identify relevant oncologic histories and therapies. CT and MR neck imaging was reviewed to characterize morphologic and enhancement characteristics of the pre- and postoperative submandibular glands, as well as interpretive accuracy.

RESULTS

Eleven patients with oropharyngeal and nasopharyngeal squamous cell carcinomas who underwent submandibular gland transfer were identified. The transferred glands were significantly lengthened in the anteroposterior dimension compared with contralateral glands (P < .001) and displaced anteriorly and inferiorly within the submandibular and submental spaces. Enhancement patterns of the transferred submandibular glands varied, depending on the time of imaging relative to the operation and radiation therapy. Submandibular gland transfer was acknowledged in the postoperative report in 7/11 cases. Errors in interpretation were present in 2/11 reports.

CONCLUSIONS

After the submandibular gland transfer procedure, the submandibular and submental spaces lose their symmetric appearances as the transferred submandibular glands become lengthened and located more anteriorly and inferiorly, with variable enhancement characteristics. Familiarity with the postsurgical appearance of the transferred submandibular glands is key to accurate imaging interpretation.

The survival impact of surgical therapy in squamous cell carcinoma of the hard palate

OBJECTIVE

To describe the incidence and determinants of survival of patients with squamous cell carcinoma of the hard palate (SCCHP) between the years of 1973 to 2014 using the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

Retrospective, population-based cohort study of patients in the SEER tumor registry who were diagnosed with SCCHP from 1973 to 2014. Outcomes and measures included overall survival (OS) and disease-specific survival (DSS).

RESULTS

A total of 1,489 cases of primary SCCHP were identified. Of those, 53.2% were females and 47.8% presented with stage IV disease. The mean age at diagnosis was 69.8 years. Overall survival at 2, 5, and 10 years was 44%, 33%, and 21%, respectively. A total of 66.2% of patients underwent surgery (with or without radiation therapy [RT]); 20.1% received RT; and 22.4% had both surgical and RT. On multivariate analysis, RT, advanced age, stage, and grade were associated with worse OS and DSS (P < 0.05). Surgical therapy (with or without radiation) was an independent favorable predictor of OS and DSS (P < 0.05).

CONCLUSION

SCCHP is relatively infrequent tumor that portends an overall poor prognosis when advanced stage and a greater prognosis when early stage. Surgical therapy was found to be an independent predictor for improved OS and DSS, whereas RT was associated with reduced OS and DSS.

LEVEL OF EVIDENCE

4. Laryngoscope, 128:2050-2055, 2018.

Abstract 17: Patterns of neck nodal metastases and recurrence in human papilloma virus-associated oropharyngeal squamous cell carcinoma after neck dissection

Background: The aim of this study is to address the paucity of data on the potentially unique patterns of neck nodal metastases in HPV-positive oropharyngeal squamous cell carcinoma (HPV+OPSCC).

Methods: The neck dissection (ND) specimens of varying levels of HPV+OPSCC patients at University of California-San Francisco from 2010-2016 were reviewed for the numbers and frequencies of clinically evident and occult nodes by neck level, and for those with extra-capsular spread (ECS). Smoking history (&gt;10 pack-years), T status, and local, regional and distal recurrences were also assessed for possible associations with nodal metastatic behavior.

Results: Sixty HPV+OPSCC patients underwent primary site trans-oral robotic surgery and 65 NDs, of which 21 (32%) were elective. Forty-three (65%) NDs were in non-smokers. Overall, the mean number of positive nodes per ND was 2.5 (range 1-9). The frequencies of at least one pathologically positive node for neck levels 1b, 2, 2a, 2b, 3, 4, and 5 were 0% (0/41), 67.7% (44/65), 43% (23/53), 13% (7/53), 27.7% (18/65), 7% (4/54), and 8% (2/23), respectively. All positive level 5 positive nodes were clinically evident preoperatively. Five of 21 (24%) elective NDs had occult disease only in levels 2A, 2B, and 3, with a mean number of positive nodes of 1.8 (range 1-3). Three of 21 (14%) elective NDs had nodes with ECS. Six of 44 (13%) therapeutic NDs had occult nodes outside the known preoperative distribution in levels 2b, 3 and 4. There were no occult 2a nodes. Smoking history, primary site, and T status were not statistically significantly associated with a differing metastatic nodal behavior. Twenty-three of 60 and 18 of 60 patients underwent adjuvant radiation and adjuvant chemoradiation, respectively. Thirteen of the 19 patients who only underwent surgery had positive lymph nodes, of which five had N1 disease and four had N2b disease. All four of N2b disease patients refused adjuvant therapy and none have had a recurrence as of follow-up (mean 28 months, range 3-51). The overall mean follow-up was 29.1 months (range 2-76 months), with 72% of patients having at least 12 months. One of 65 (1.5%) NDs developed a neck recurrence in the skin overlying level 2 in a patient in the therapeutic ND cohort who had undergone chemoradiation for ECS. No undissected neck levels developed metastatic nodal disease. Two of 60 (3%) patients developed local recurrence. No patients developed distant metastases. One patient in the cohort died of an unrelated cause. There have been no cancer-related deaths.

Conclusions: For HPV+OPSCC, therapeutic NDs should encompass any levels bearing suspicious nodes and levels 2a, 2b, 3, and 4, while elective NDs should be performed and encompass at least levels 2a, 2b, and 3. ECS may be present in occult nodes. For HPV+OPSCC, these selective ND plans, followed by the indicated adjuvant treatment, is associated with a low neck recurrence rate.

Citation Format: Madeleine P. Strohl, Steven J. Wang, Patrick K. Ha, Jonathan R. George, Chase M. Heaton, Ivan H. El-Sayed, Jon Mallen St Clair, William R. Ryan. Patterns of neck nodal metastases and recurrence in human papilloma virus-associated oropharyngeal squamous cell carcinoma after neck dissection [abstract]. In: Proceedings of the AACR-AHNS Head and Neck Cancer Conference: Optimizing Survival and Quality of Life through Basic, Clinical, and Translational Research; April 23-25, 2017; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(23_Suppl):Abstract nr 17.

STAT3 Expression and Activity are Up-Regulated in Diffuse Large B Cell Lymphoma of Dogs

Background

The Janus Kinase (JAK) and Signal Transducer and Activator of Transcription (STAT) pathways play important roles in the pathogenesis of diffuse large B cell lymphoma (DLBCL) in humans, and up‐regulated STAT3 expression and activity are associated with worse clinical outcome in humans. No studies have evaluated the JAK‐STAT signaling pathway in DLBCL of dogs.

Hypothesis

STAT3 pathway is deregulated in DLBCL in dogs. We aim to assess the expression, activation, and cellular localization of STAT3 and mitogen‐activated protein kinase ERK1/2 in DLBCL of dogs.

Animals

Forty‐three client‐owned dogs diagnosed with DLBCL by histopathology

Methods

Retrospective analysis of DLBCL in dogs, including patient characteristics and treatment, immunohistochemistry, and protein expressions by Western blot.

Results

A higher percentage of STAT3 and p‐STAT3 immunolabelled cells were observed in DLBCL of dogs when compared to normal canine lymph nodes. In STAT3 immunolabelled cells, STAT3 has higher nuclear expression in lymphoma samples than in normal or reactive lymph nodes. In addition to up‐regulated STAT3 expression and activation, mitogen‐activated kinase ERK1/2 activation is up‐regulated in DLBCL of dogs.

Conclusion and Clinical Importance

Compared with the normal canine lymph node, DLBCL of dogs has up‐regulated STAT3 pathway. Our results support future investigation of JAK inhibitors in the treatment of DLBCL in dogs.

Volumetric Growth Rate of Recurrent Pleomorphic Adenoma

Objectives:

Surgery for recurrent pleomorphic adenoma (PA) can be challenging and may increase the risk of operative complications, particularly facial nerve weakness. As observation may be a viable alternative to surgery for slow-growing tumors, our objective was to assess the growth rate of recurrent PAs.

Study Design:

This study is a case series of patients at our tertiary academic medical center with recurrent PA. Two magnetic resonance images (MRI) were compared; total volume (TV) of recurrent tumor on both studies was calculated to obtain our main outcomes of percent change in TV and tumor growth rate.

Results:

Fourteen patients with recurrent PA had a median interval time between MRI of 12.8 months. Though growth rates were variable, the median continuous compound growth per year was 10.2%. Notably, 3 patients (21%) had no growth, and 2 patients (14%) had a reduction in TV.

Conclusions:

The median growth rate for enlarging tumors is estimated at 10.2% per year. Due to variability, tumor growth rate should be estimated on an individual patient basis. For slow-growing tumors, physicians may weigh the risk of this slow growth with the morbidity of reoperation.

Transoral robotic surgery (TORS) for excision of a retropharyngeal intramuscular lipoma

OBJECTIVE

To describe the feasibility, effectiveness, and improved morbidity profile of transoral robotic surgery (TORS) for the excision of a retropharyngeal intramuscular lipoma.

METHODS

Case report of a robot-assisted transoral resection of a retropharyngeal intramuscular lipoma.

RESULTS

A 62-year-old woman presented with tongue pain and globus with dysphagia for six months. Transoral exam revealed a pharyngeal submucosal mass, and MRI demonstrated a prevertebral lipomatous lesion with protrusion into the airway. The patient elected for robot-assisted transoral surgical treatment. The patient tolerated the procedure well, experienced no complications, and was discharged on post-operative day one. At six months post-operatively, the patient was without dysphagia and was disease free on imaging.

CONCLUSIONS

TORS is an effective, safe, feasible, and likely more efficient way to excise a retropharyngeal intramuscular lipoma or other retropharyngeal masses.

Clinicopathologic characteristics and outcomes of recurrent oropharyngeal squamous cell carcinoma

PURPOSE

Positive p16 immunohistochemical staining is predictive of improved survival and response to treatment. The purpose of this study is to determine the clinicopathologic characteristics and outcomes of patients with p16+ oropharynx cancer who fail initial treatment.

MATERIALS AND METHODS

Case series including all patients with recurrent oropharyngeal squamous cell carcinoma from 2002 to 2014.

RESULTS

Forty patients met inclusion criteria. Thirty-one (77.5%) tumors were p16+ and 9 (22.5%) were p16-. There was no difference in T/M stage at diagnosis; more patients with p16+ tumors presented initially with ≥N2 disease (p=0.04). Regional and/or metastatic recurrence was more common in the p16+ group as compared to the p16- group - 71% vs 22.2%, p=0.003. Outcomes for both groups were poor - 67.7% p16+ and 44.4% p16- patients died from disease.

CONCLUSIONS

Compared to p16- recurrent tumor patients, p16+ recurrent tumor patients were more likely to experience regional or distant metastatic recurrence. Overall outcomes for both p16+ and p16- recurrent oropharynx tumors were poor.

Volumetric Growth of Cervical Schwannoma as a Predictor of Surgical Intervention

Objective

Cervical schwannomas are benign tumors that commonly present as asymptomatic masses and are managed with observation, radiation, or surgery. To our knowledge, the rate of volumetric change seen on serial imaging is not currently used to determine surgical candidacy. We assess average growth rates and determine whether growth rate of cervical schwannoma predicts having undergone surgery.

Study Design

Case series with chart review.

Setting

Quaternary academic medical center.

Subjects and Methods

Patients were identified with at least 2 imaging studies and pathologic or imaging characteristics of cervical schwannoma. Volume was calculated with the formula 4/3π xyz, with x, y, and z representing the 3 orthogonal dimensions. Volume and rate of volume change were compared among observed, surgical, and gamma knife groups.

Results

Thirteen patients were identified and divided into subgroups: surgical (n = 5), observation (n = 6), and gamma knife (n = 2). Mean follow-up time was 21 months (range, 1-80 months) and not significantly different among subgroups. The average changes in volume were 3.61 cm3/mo (entire group), –2.75 cm3/mo (observation), 11.97 cm3/mo (surgery), and 1.78 cm3/mo (gamma knife). Average initial volume for the entire group was 124.4 cm3 (range, 5-608 cm3) and 142 cm3 (range 5-613) at follow-up. The surgical group had a statistically significant change in volume ( P = .03). A statistically significant difference in growth rate was seen between the surgical and observation groups ( P = .016) and between the surgical group and all nonsurgical patients ( P = .011).

Conclusions

Rate of tumor growth can be used in the evaluation of patients with cervical schwannoma, and it may predict surgical intervention.

Targeted next-generation sequencing of TP53 in oral tongue carcinoma from non-smokers

Background

Little is known regarding the etiology and genomic underpinnings of Oral Tongue Squamous Cell Carcinoma (OTSCC) in patients who lack traditional risk factors, yet the incidence is increasing. In particular, the rate, and role, of TP53 mutations in this cohort has been heavily debated in the literature.

Methods

Tumor DNA from forty-three non-smokers with OTSCC underwent next generation sequencing of TP53.

Results

Sixty percent of samples contained a TP53 mutation. The G > T transversion rate was 5.7 %. TP53 status did not differ by age.

Conclusions

OTSCC in non-smokers have TP53 mutation rates similar to other Head and Neck cancers yet these mutations do not appear related to carcinogen exposure based on the mutational spectrum and clinical history. The mechanisms driving tumorigenesis in this cohort, including mutations in TP53, remain elusive and further studies are needed.

Electronic supplementary material

The online version of this article (doi:10.1186/s40463-016-0160-4) contains supplementary material, which is available to authorized users.