Targeting TGF beta receptor 1 in head and neck squamous cell carcinoma

OBJECTIVES

The transforming growth factor-Beta (TGF-ß) pathway may be involved in the radioresistance of head and neck squamous cell carcinoma (HNSCC). This study analyzed TGF-ß receptor 1 (TGFBR1) expression in HNSCC patients and evaluated the antineoplastic and radiosensitizing effects of vactosertib, a novel TGFBR1 inhibitor, in vitro.

MATERIALS AND METHODS

TGFBR1 expression was examined in HNSCC patients at the mRNA level in silico and the protein level by immunohistochemistry, including surgical specimens of primary tumors, matched lymph node metastasis, and recurrent disease. Furthermore, a novel small molecule TGFBR1 inhibitor was evaluated in HNSCC cell lines. Finally, an indirect coculture model using patient-derived cancer-associated fibroblasts was applied to mimic the tumor microenvironment.

RESULTS

Patients with high TGFBR1 mRNA levels showed significantly worse overall survival in silico (OS, p = 0.024). At the protein level, an association between TGFBR1+ tumor and OS was observed for the subgroup with TGFBR1-stroma (p = 0.001). Those results prevailed in multivariable analysis. Inhibition of TGFBR1 showed antineoplastic effects in vitro. In combination with radiation, vactosertib showed synergistic effects.

CONCLUSION

Our results indicate a high risk of death in tumorTGFBR1+|stromaTGFBR1- expressing patients. In vitro data suggest a potential radiosensitizing effect of TGFBR1 inhibition by vactosertib.

The dual role of autophagy in HPV-positive head and neck squamous cell carcinoma: a systematic review

PURPOSE

Human papilloma virus (HPV)-positive head and neck squamous cell carcinoma (HNSCC) displays distinct epidemiological, clinical, and molecular characteristics compared to the negative counterpart. Alterations in autophagy play an important role in cancer, and emerging evidence indicates an interplay of autophagy in HNSCC carcinogenesis and tumor promotion. However, the influence of HPV infection on autophagy in HNSCC has received less attention and has not been previously reviewed. Therefore, we here aimed to systematically review the role of autophagy explicitly in HPV+ HNSCC.

METHODS

Studies accessible in PubMed, Embase, Scopus, and Web of Science investigating HNSCC, highlighting the molecular biological differences between HPV- and HPV+ HNSCC and its influences on autophagy in HNSCC were analyzed according to the PRISMA statement. A total of 10 articles were identified, included, and summarized.

RESULTS

The HPV16 E7 oncoprotein was reported to be involved in the degradation of AMBRA1 and STING, and to enhance chemotherapy-induced cell death via lethal mitophagy in HNSCC cells. Autophagy-associated gene signatures correlated with HPV-subtype and overall survival. Additionally, immunohistochemical (IHC) analyses indicate that high LC3B expression correlates with poor overall survival in oropharyngeal HNSCC patients.

CONCLUSION

HPV may dampen general bulk autophagic flux via degradation of AMBRA1 but may promote selective autophagic degradation of STING and mitochondria. Interpretations of correlations between autophagy-associated gene expressions or IHC analyses of autophagy-related (ATG) proteins in paraffin embedded tissue with clinicopathological features without biological validation need to be taken with caution.

Lymphocyte-to-Monocyte Ratio Might Serve as a Prognostic Marker in Young Patients with Tongue Squamous Cell Carcinoma

BACKGROUND

Young patients with tongue squamous cell carcinoma (TSCC) mostly lack typical prognostic markers and face a dire prognosis. The aim of this study was to analyze the prognostic relevance of lymphocyte-to-monocyte ratio (LMR) in TSCC patients, with a special emphasis on patients under 45 years.

METHODS

This retrospective study included all patients primarily treated for TSCC. The prognostic relevance of LMR was investigated in terms of predicting the overallsurvival (OS) and disease-free survival (DFS).

RESULTS

A total of 74 patients were included and the young cohort (<45 years) comprised 27 individuals. The mortality and recurrence rates were 39.2% (n = 29) and 37.8% (n = 28), respectively. OS and DFS were significantly shorter in the low LMR group within the whole cohort. Furthermore, low LMR was associated with worse prognosis, particularly inferior OS (median OS 1.7 vs. 14.6 years, p = 0.0156) and worse DFS (median DFS 0.8 years vs. not reached, p = 0.0405) in the young patient cohort.

CONCLUSIONS

Our results reveal that pretreatment LMR might become a prognostic tool for young TSCC patients, especially due to its availability. However, further studies on larger cohorts are necessary to validate our results.

The ATR inhibitor berzosertib acts as a radio- and chemosensitizer in head and neck squamous cell carcinoma cell lines

Alterations in the DNA damage response play a crucial role in radio- and chemoresistance of neoplastic cells. Activation of the Ataxia telangiectasia and Rad3-related (ATR) pathway is an important DNA damage response mechanism in head and neck squamous cell carcinoma (HNSCC). Berzosertib, a selective ATR inhibitor, shows promising radio- and chemosensitizing effects in preclinical studies and is well tolerated in clinical studies. The aim of this study was to elucidate the effect of berzosertib treatment in combination with radiation and cisplatin in HNSCC. The HNSCC cell lines Cal-27 and FaDu were treated with berzosertib alone and in combination with radiation or cisplatin. Cell viability and clonogenic survival were evaluated. The effect of combination treatment was evaluated with the SynergyFinder or combination index. Apoptosis was assessed via measurement of caspase 3/7 activation and migration was evaluated using a wound healing assay. Berzosertib treatment decreased cell viability in a dose-dependent manner and increased apoptosis. The IC50 of berzosertib treatment after 72 h was 0.25-0.29 µM. Combination with irradiation treatment led to a synergistic increase in radiosensitivity and a synergistic or additive decrease in colony formation. The combination of berzosertib and cisplatin decreased cell viability in a synergistic manner. Additionally, berzosertib inhibited migration at high doses. Berzosertib displays a cytotoxic effect in HNSCC at clinically relevant doses. Further evaluation of combination treatment with irradiation and cisplatin is strongly recommended in HNSCC patients as it may hold the potential to overcome treatment resistance, reduce treatment doses and thus mitigate adverse events.

In vitro antineoplastic effects of MK0752 in HPV-positive head and neck squamous cell carcinoma

PURPOSE

Gamma-secretase inhibitor MK0752 has shown a high therapeutic potential in different solid malignant tumors. Up to now, its antineoplastic effects were not investigated in head and neck squamous cell carcinoma (HNSCC) and particularly in human-papillomavirus (HPV)-positive tumors.

METHODS

We conducted cytotoxic, migration, and clonogenic assays in two HPV-negative HNSCC cell lines (Cal27 and FaDu) and one HPV-positive cell line (SCC154). Furthermore, in order to assess the pro-apoptotic effects of MK0752, a Caspase 3/7 Glo assay was performed.

RESULTS

Our experiments revealed antineoplastic effects of MK0752 in all three cell lines. Strong cytotoxic and antimigratory potential was shown in all cell lines, with strongest effects observed in the HPV-positive cell line. Meanwhile, anticlonogenic effects were only shown in Cal27 and SCC154. Most importantly, MK0752 induced apoptosis solely in HPV-positive SCC154.

CONCLUSIONS

Our novel findings indicate a therapeutic potential of MK0752 in HPV-positive HNSCC. Indeed, further investigation is needed for validation of our results and for the assessment of the mechanistic background.

Low free triiodothyronine and immune-related hyperthyroidism are associated with overall and progression-free survival in head and neck squamous cell carcinoma treated with pembrolizumab

INTRODUCTION

Thyroid function is frequently impaired in recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC). In patients treated with pembrolizumab, immune-related adverse events (irAEs) of the thyroid are common. However, the prognostic significance of baseline and on-treatment thyroid dysfunction is currently unclear.

METHODS

This study included 95 patients who received pembrolizumab for R/M HNSCC between 2016 and 2022. Baseline thyroid status, according to serum hormone levels, and irAEs were assessed. Univariable and multivariable Cox regression analyses were performed for overall survival (OS) and progression-free survival (PFS). Furthermore, the best overall response according to the prognostic groups was examined.

RESULTS

Low fT3 (HR: 2.52, p = 0.006), immune-related hyperthyroidism (HR: 0.11, p = 0.038), ECOG performance status ≥2 (HR: 3.72, p = 0.002), and platinum-refractory disease (HR: 3.29, p = 0.020) were independently associated with OS. Furthermore, immune-related hyperthyroidism was associated with longer PFS (HR: 0.13, p = 0.007), a higher objective response rate (83% vs. 31%, p = 0.018), and a higher disease control rate (100% vs. 43%, p = 0.008). Thyroid-related autoantibodies were elevated in 40% of thyroid irAEs cases with available measurements. Out of 16 thyroid irAEs, 15 occurred in patients with fT3 above the lower limit of normal.

CONCLUSION

Low fT3 was associated with worse OS. Immune-related hyperthyroidism was correlated with both improved OS and PFS. Baseline fT3 assessment and close on-treatment monitoring of serum thyroid levels may be valuable for risk stratification in R/M HNSCC patients receiving pembrolizumab.

Early on-treatment C-reactive protein and its kinetics predict survival and response in recurrent and/or metastatic head and neck cancer patients receiving first-line pembrolizumab

PURPOSE

First-line immune checkpoint blockade has improved the prognosis of recurrent and/or metastatic head and neck squamous cell carcinoma (R/M HNSCC), but response rates remain low. In this study, we aimed to investigate the prognostic value of CRP and its early kinetics to predict response and survival in R/M HNSCC.

METHODS

A total of 87 patients who received first-line pembrolizumab for R/M HNSCC were analyzed. Three-fold cross-validation was used to estimate cut-off points of CRP at baseline and on-treatment (day 40 ± 10). Treatment response and survival were analyzed according to early CRP kinetics. The neutrophil-to-lymphocyte ratio (NLR) was used as a benchmark for the prognostic performance of CRP.

RESULTS

On-treatment CRP below 2 mg/dl, 4x the upper limit of normal (ULN), was associated with increased overall survival (OS), while on-treatment CRP below 3 mg/dl (6x ULN) was correlated with a higher disease control rate (DCR) and increased progression-free survival (PFS). CRP flare-responders and CRP responders showed a higher DCR and longer PFS than CRP non-responders. An NLR above 6 was a negative prognosticator for progression. In multivariable analysis, on-treatment CRP prevailed as the only significant prognosticator for OS (HR: 4.97, CI95%: 2.18-11.32, p < 0.001) and PFS (HR: 2.07, CI95%: 1.07-3.99, p = 0.030).

CONCLUSION

On-treatment CRP was identified as a prognostic biomarker for objective response and survival in R/M HNSCC patients receiving first-line pembrolizumab and could be easily incorporated into clinical practice as a widely available and cost-effective biomarker.

High USP4 mRNA is associated with an HPV-positive status in head and neck squamous cell carcinoma patients

INTRODUCTION

Head and neck squamous cell carcinoma (HNSCC) is among the most common cancers in the world with a low survival rate and common diagnosis at late stages. Deubiquitination of proteins is involved in tumor growth, metastasis, apoptosis, and immunosuppressive pathways. The impact of the ubiquitin-specific protease (USP4) on survival was only scarcely investigated so far. The goal of our research was to analyze the association of USP4 expression with prognosis and clinicopathological features in HNSCC.

METHODS

USP4 mRNA levels were derived from The Cancer Genome Atlas (TCGA) for a cohort of 510 patients. Protein expression of USP4 was analyzed by immunohistochemistry in a second cohort of 113 patients. Associations between USP4 levels and overall survival, disease-free survival and clinicopathological data were analyzed.

RESULTS

High levels of USP4 mRNA were associated with prolonged overall survival in univariable analysis. There was no more association with survival after correction for the confounders HPV, stage and smoker status. High USP4 mRNA levels were linked to a lower T-stage, the patient's age at diagnosis, and a positive HPV status. USP4 protein levels were not associated with prognosis or other features.

CONCLUSION

Since high USP4 mRNA was not an independent prognostic marker, we assume that the association is a result of the correlation of high USP4 mRNA with an HPV-positive status. Therefore, further investigation of USP4 mRNA and its association with the HPV status of HNSCC patients is warranted.

β-CATENIN is a positive prognostic marker for HPV-positive head and neck squamous cell carcinoma

PURPOSE

The evolutionary-conserved Wnt/β-CATENIN (WBC) pathway has been implicated in the pathogenesis of different solid malignant tumors. We evaluated the prognostic relevance of β-CATENIN, a pivotal mediator of WBC activation, in patients with human papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HNSCC).

METHODS

We analyzed if patients with HPV-positive HNSCC from the "The Cancer Genome Atlas" (TCGA cohort, n = 41) can be stratified based on their CTNNB1 mRNA expression. Moreover, in a tissue microarray (TMA) of primary tumor sections from HPV-positive HNSCC patients treated in a tertiary academic center (in-house cohort, n = 31), we evaluated the prognostic relevance of β-CATENIN expression on protein level.

RESULTS

In silico mining of CTNNB1 expression in HPV-positive HNSCC revealed that high CTNNB1 expression was linked to better overall survival (OS, p = 0.062). Moreover, high β-CATENIN expression was significantly associated with a better OS in our in-house cohort (p = 0.035).

CONCLUSION

Based on these findings, we postulate that β-CATENIN expression could serve (potentially in conjunction with other WBC pathway members) as a marker for better survival outcomes in patients with HPV-positive HNSCC. However, it is evident that future studies on bigger cohorts are warranted.

In vitro effects of gamma-secretase inhibition in HPV-positive and HPV-negative head and neck squamous cell carcinoma

BACKGROUND

New chemotherapy agents are warranted for head and neck squamous cell carcinoma (HNSCC), particularly for incidence-rising HPV-positive tumors. Based on the evidence of Notch pathway involvement in cancer promotion and progression, we aimed to gain insights into the in vitro antineoplastic effects of gamma-secretase inhibition in HPV-positive and -negative HNSCC models.

METHODS

All in vitro experiments were conducted in two HPV-negative (Cal27 and FaDu) and one HPV-associated HNSCC cell line (SCC154). The influence of the gamma-secretase inhibitor PF03084014 (PF) on proliferation, migration, colony forming, and apoptosis was assessed.

RESULTS

We observed significant anti-proliferative, anti-migratory, anti-clonogenic, and pro-apoptotic effects in all three HNSCC cell lines. Furthermore, synergistic effects with concomitant radiation were observable in the proliferation assay. Interestingly, effects were slightly more potent in the HPV-positive cells.

CONCLUSION

We provided novel insights into the potential therapeutic relevance of gamma-secretase inhibition in HNSCC cell lines in vitro. Therefore, PF may become a viable treatment option for patients with HNSCC, particularly for patients with HPV-induced malignancy. Indeed, further in vitro and in vivo experiments should be conducted to validate our results and decipher the mechanism behind the observed anti-neoplastic effects.

Inhibition of beta-catenin shows therapeutic potential in head and neck squamous cell carcinoma in vitro

Beta-catenin is known to be a vital component of the canonical Wnt signaling cascade, involved in the carcinogenesis of different solid tumors. We aimed to evaluate the effects of Beta-catenin inhibition in head and neck squamous cell carcinoma (HNSCC) in vitro. The small molecular compound MSAB was used to inhibit Wnt/Beta-catenin signaling in a human papillomavirus (HPV)-positive and HPV-negative cell line and its effects on cell proliferation, migration, colony formation, apoptosis, as well as radiosensitizing properties were assessed. Significant antineoplastic effects were observed in both cell lines. Interestingly, stronger anti-neoplastic and radiosensitizing effects were observed in the HPV-negative cell line, whereas stronger anti-migratory potential was detected in HPV-positive HNSCC cells. In conclusion, our findings suggest MSAB as a potential therapeutic agent for HNSCC. Further studies are warranted to unravel the mechanistic background of our findings.

Evaluation of the Prognostic Capacity of a Novel Survival Marker in Patients with Sinonasal Squamous Cell Carcinoma

Sinonasal squamous cell carcinoma (SNSCC) is a malignant tumor associated with poor survival, and easily obtainable prognostic markers are of high interest. Therefore, we aimed to assess the prognostic value of a novel survival index (SI) combining prognostic values of clinical (T and N classifications and invasion across Ohngren’s line), inflammatory (neutrophil-to-lymphocyte ratio), and nutritional (albumin and body-mass index) markers. All patients with primarily treated SNSCC between 2002 and 2020 (n = 51) were included. Each of the six SI components was stratified into a low- (0) and high-risk (1) categories. Subsequently, the cohort was stratified into low- (SI of 0–2) and high-risk SI groups (SI of 3–6). Overall survival (OS) and disease-free survival (DFS) were compared between patients with low- and high-risk SI. The log-rank test was used to test for statistical significance. Overall, the mortality rate was 41.2% (n = 21), and the recurrence rate was 43.1% (n = 22). We observed significantly better OS in patients with low-risk SI (n = 24/51, 47.1%, mean OS: 7.9 years, 95% confidence interval (CI): 6.3–9.6 years) than in high-risk SI (n = 27/51, 52.9%, mean OS: 3.4 years, 95% CI: 2.2–4.5 years; p = 0.013). Moreover, we also showed that patients with low-risk SI had a longer DFS than patients with high-risk SI (mean DFS: 6.4, 95% CI: 4.8–8.0 vs. mean DFS: 2.4 years, 95% CI 1.3–3.5, p = 0.012). The SI combines the prognostic capacity of well-established clinical, radiologic, inflammatory, and nutritional prognosticators and showed prognostic potential in our cohort of SNSCC patients.

The prognostic role of PSMD14 in head and neck squamous cell carcinoma

PURPOSE

PSMD14 is an essential protein for proteasomal degradation. Inhibition of this protein disrupts homeostasis and inhibits cancer cell viability. Overexpression of PSMD14 was associated with advanced cancer characteristics and a worse prognosis in various carcinomas. This study aimed to analyze PSMD14 copy number variation, mRNA and protein expression in HNSCC, and its role as an independent prognostic biomarker.

METHODS

PSMD14 mRNA expression and copy number variations were analyzed in "The Cancer Genome Atlas (TCGA)" in 510 patients. Protein expression was evaluated using immunohistochemistry in a second cohort including 115 patients. PSMD14 levels were analyzed for correlation with clinicopathological data, overall and disease-free survival.

RESULTS

PSMD14 mRNA expression and copy number variation were high in 44 and 50% of patients, respectively. Protein expression of PSMD14 was high in 56%. In both cohorts, high PSMD14 levels were associated with advanced staging. High PSMD14 mRNA expression was additionally associated with a worse prognosis in univariable analysis. However, after correction for possible confounders, PSMD14 mRNA was not an independent prognostic marker.

CONCLUSION

PSMD14 is commonly expressed in HNSCC patients and associated with advanced stages. High expression of PSMD14 mRNA was associated with a worse outcome. However, this may be a result of the association of PSMD14 with poor prognosticators. Based on our study, further evaluation of PSMD14 as a prognostic marker and potential therapeutic target is warranted.

Protein Expression of Folate Receptor Alpha in Adenoid Cystic Carcinoma of the Head and Neck

Purpose

Folate receptor alpha (FRα) is overexpressed in various cancer entities while expression in normal tissue is limited. Thus, FRα is an attractive target in cancer therapy. Currently, various therapeutic and diagnostic approaches are under investigation in clinical trials. The aim of this study was to assess the expression and clinical relevance of FRα in adenoid cystic carcinoma of the head and neck.

Patients and Methods

In this retrospective cohort study, 43 patients with adenoid cystic carcinoma (ACC) of the head and neck were included. FRα expression was analyzed in tumor tissue and tumor-free margin in a tissue microarray using immunohistochemical staining. Protein levels were correlated with clinical parameters.

Results

FRα staining was positive in 47% of ACC patients. The tumor-free margin was positive in 22%. Patients with positive tumor tissue showed positive margin staining in 55%. FRα expression was not associated with the clinical parameters (sex, age, staging, grading, perineural invasion, lymphovascular invasion).

Conclusion

FRα expression is common in ACC of the head and neck. Therefore, FRα should be further evaluated as a therapeutic target in ACC.

Pretherapeutic Serum Albumin as an Outcome Prognosticator in Head and Neck Adenoid-Cystic Carcinoma

Background: A head and neck adenoid-cystic carcinoma is a rare malignant tumor arising from the salivary gland tissues. The long-term survival outcome is poor due to a high risk of recurrences and distant metastasis. The identification of prognostic markers could contribute to a better risk assessment of each patient. The aim of this study is to assess the potential prognostic value of serum albumin in patients with head and neck adenoid-cystic carcinomas. Patients and Methods: This retrospective cohort study included all patients treated for a head and neck adenoid-cystic carcinoma between 1993 and 1 June 2019 with available pretherapeutic albumin values and clinical follow-up data. The cohort was stratified into a high and low group according to the median albumin value. The log-rank test was used for comparing overall and disease-free survival. Results: A total of 37 patients with complete follow-up data and available pretreatment albumin values were available. The overall mortality and recurrence rates were 21.6% (n = 8) and 45.9% (n = 17), respectively. Survival was shorter in the low albumin group. In particular, the mean overall survival for the low and high albumin groups were 121.0 months and 142.8 months, respectively. However, the difference was not statistically significant (p = 0.155). A statistically significant difference was observed in context with disease-free survival (45.2 months, 95% confidence interval 31.7–58.8 months vs. 114.8 months, 95% confidence interval 79.3–150.4 months; p = 0.029). Conclusion: Our study suggests a potential prognostic value of serum albumin in patients with a head and neck ACC. A further, external validation of our results is warranted.

Prognostic Relevance of Thyroid-Hormone-Associated Proteins in Adenoid Cystic Carcinoma of the Head and Neck

The proteins sodium iodide symporter (NIS), μ-crystallin (CRYM), and thyroid hormone receptor beta (THRB) have been associated with prognosis in various cancer entities. While NIS and THRB may serve as possible therapeutic targets, the role of CRYM in cancer is still unclear. Protein levels of 44 patients with adenoid cystic carcinoma of the head and neck were analyzed using immunohistochemistry and correlated with clinicopathological data and outcome. NIS was positive in 72%, CRYM was positive in 55%, and THRB was positive in 39% of the patients. CRYM-positive adenoid cystic carcinomas were associated with a better cause-specific survival. Thus, our data indicate that CRYM might be a suitable positive prognostic marker in adenoid cystic carcinoma of the head and neck. Furthermore, expression of NIS was present in most patients and therefore evaluation of the use of radioiodine treatment is recommended.

The Potential Prognostic Value of a Novel Hematologic Marker Fibrinogen-to-Lymphocyte Ratio in Head and Neck Adenoid-Cystic Carcinoma

Many patients with adenoid-cystic carcinoma (ACC) experience an indolent course of disease over many years but face late recurrence, and long-term survivors are rare. Due to its infrequent occurrence, it is hard to predict outcome in these patients. The fibrinogen-to-lymphocyte ratio (FLR) was recently proposed as an outcome prognosticator in different cancer entities. We aimed to investigate its prognostic relevance in patients with head and neck ACC. This retrospective analysis was performed including all patients treated for ACC between 1998 and 2020. The FLR ratio was calculated based on pretreatment values (0-7 days). The study cohort was dichotomized based on optimized threshold value and compared for differences in outcome (overall survival (OS) and disease-free survival (DFS)). In the cohort of 39 included patients, the OS was significantly longer in the low (n = 28) compared to the high pretreatment FLR group (n = 11) (median OS 150.5 months, 95% confidence intervals (CI) 85.3-215.7 months vs. 29.4 months, 95% CI not reached; p = 0.0093). Similarly, the DFS was significantly longer in the low FLR group (median DFS 74.5 months, 95% CI 30.6-118.4 months vs. 11.0 months, 95% CI 5.1-16.9 months; p = 0.019). The FLR is an easily obtainable and simple marker and may be a valuable outcome prognosticator in patients with ACC. Further studies are needed for validation of our results.

Potential association of the prognostic index and survival in patients with p16-positive oropharyngeal squamous cell carcinoma

Background

The aim was to assess the prognostic value of the newly proposed prognostic index (PI) in patients with p16-positive oropharyngeal squamous cell carcinoma.

Methods

Patients treated with primary surgery from 2012 to 2019 with available preoperative (0–2 days) values of C‑reactive protein and white blood cell counts needed for calculation of the PI, were included. Main outcome measures were overall survival (OS) and disease-free survival (DFS). The PI was dichotomized into low (PI = 0) and high (PI ≥ 1).

Results

In this study 36 patients were included. Average overall (OS) and disease-free survival (DFS) were 3.3 years (range 0.2–12.3 years) and 2.8 years (0.0–9.8 years), respectively. The overall mortality was 16.7% (n = 6) and a recurrent disease was observed in 30.6% of patients (n = 11). Low PI was associated with better overall survival (mean OS 10.1 ± 1.4 years, 95% confidence interval, CI 7.3–12.9 years vs. 1.9 ± 0.4, 95% CI 1.3–2.6 years, p < 0.01; mean DFS 8.5 ± 0.7 years, 95% CI 7.1–9.6 years vs. 1.0 ± 0.3 years, 95% CI 0.5–1.5 years, p < 0.01).

Conclusion

The PI might be an easily obtainable outcome prognosticator in p16-positive oropharyngeal squamous cell carcinoma patients. Analyzing routinely obtained blood samples can contribute to identifying high-risk patients.