The Clinical Utility and Cost of Routine Staging Exam under Anesthesia for Oral Cavity Squamous Cell Carcinoma

INTRODUCTION

The standard complete evaluation of patients with head and neck squamous cell carcinoma (HNSCC) has included a staging exam under anesthesia (EUA) since the 1970s. The EUA for all sites of HNSCC has historically consisted of panendoscopy for the purpose of diagnostic biopsy, accurate staging of primary disease, and identification of second primary tumors. However, due to the accessibility of the oral cavity, the sole purpose of EUA for tumors of this site is to identify second primary tumors. Since the EUA became the gold standard for evaluation of HNSCC, there have been significant advancements in less invasive technologies such as CT, PET-CT, MRI, and fiberoptic examination. In this study, we sought to determine the value to patient care and cost-effectiveness of EUA in patients with oral cavity squamous cell carcinoma (OCSCC).

METHODS

A retrospective chart review identified 77 patients who underwent EUA for OCSCC.

RESULTS

The most common subsites were the oral tongue and floor of mouth (59.7% and 24.7% respectively). All underwent direct laryngoscopy, 94.8% underwent esophagoscopy, and 20.8% underwent flexible transnasal examination in clinic prior to EUA. For 90.9% of patients, the EUA did not change initial T-staging based on clinical examination and imaging. The remaining 9.1% of patients were upstaged after EUA, however this change did not impact the treatment plan. Second primary tumors were identified in 3.9% of patients, all were found in either the oral cavity or oropharynx, and were also identified with clinical examination or imaging. Analysis of patient charges determined an average cost of $8,022.93 per patient under the current paradigm involving EUA, however with a new algorithm eliminating mandatory EUA average cost decreases to $1,448.44.

CONCLUSION

Formal EUA has historically been the gold standard for all HNSCC tumors. However, when performed for cases of oral cavity carcinoma, it is safe and cost effective to limit its use to select clinical scenarios.

Non-HPV-Related Head and Neck Squamous Cell Carcinoma in a Young Patient Cohort

OBJECTIVES

Head and neck squamous cell carcinoma (HNSCC) is rare in patients younger than 40 years. Many practitioners suspect HNSCC is a more aggressive disease in this age group, and perhaps increasing in incidence; however, there are scant and conflicting data to support this assertion. We sought to compare outcomes for young patients with non-human papillomavirus (HPV)-related HNSCC to those of older patients.

METHODS

A retrospective chart review of patients with HNSCC treated from 2004 to 2016 at 2 tertiary referral centers. Patients aged 18 to 40 with p16-negative HNSCC were included in the young patient cohort (n = 59). A randomly selected stage- and subsite-matched cohort aged 55 to 65 was analyzed for comparison (n = 114).

RESULTS

When considering all patients with HNSCC, patients younger than 40 were more likely to have oral tongue cancer (62.7%) compared to patients age 55 to 65 (16.9%). When an older patient cohort was stage- and subsite-matched to the young patient cohort, there were more never smokers (49.2% vs 17.5% of older patients, P < .01) and females (40.7% vs 24.6% of older patients, P = .028) in the young patient group. The young patient cohort had better average overall survival than the older group (14.4 vs 8.1 years, respectively, P = .02), but similar average disease-free survival (6.2 years vs 6.6 years, respectively, P = .67); 50.9% of young patients had tumors with adverse histologic features versus 42.0% of older patients (P = .28). The young patients demonstrated a superior average conditional survival after recurrence (9.8 years vs 3.2 years for older patients, P < .01).

CONCLUSIONS

Despite the limitations of study design, these data suggest that young patients who develop non-HPV-related HNSCC tend to have similarly aggressive disease, but longer overall survival and better survival after recurrence. These findings may be attributable to better overall health as evidenced by fewer comorbidities.

PRAS40 Phosphorylation Correlates with Insulin-Like Growth Factor-1 Receptor-Induced Resistance to Epidermal Growth Factor Receptor Inhibition in Head and Neck Cancer Cells

EGFR inhibitors have shown poor efficacy in head and neck squamous cell carcinoma (HNSCC) with demonstrated involvement of the insulin-like growth factor-1 receptor (IGF1R) in resistance to EGFR inhibition. IGF1R activates the PI3K-Akt pathway, which phosphorylates proline-rich Akt substrate of 40 kDa (PRAS40) to cease mTOR inhibition resulting in increased mTOR signaling. Proliferation assays separated six HNSCC cell lines into two groups: sensitive to EGFR inhibition or resistant; all sensitive cell lines demonstrated reduced sensitivity to EGFR inhibition upon IGF1R activation. Reverse phase protein microarray analysis and immunoblot identified a correlation between increased PRAS40 phosphorylation and IGFR-mediated resistance to EGFR inhibition. In sensitive cell lines, PRAS40 phosphorylation decreased 44%-80% with EGFR inhibition and was restored to 98%-196% of control by IGF1R activation, while phosphorylation was unaffected in resistant cell lines. Possible involvement of mTOR in this resistance mechanism was demonstrated through a similar pattern of p70S6K phosphorylation. However, addition of temsirolimus, an mTORC1 inhibitor, was insufficient to overcome IGF1R-mediated resistance and suggested an alternative mechanism. Forkhead box O3a (FOXO3a), which has been reported to complex with PRAS40 in the cytoplasm, demonstrated a 6-fold increase in nuclear to cytoplasmic ratio upon EGFR inhibition that was eliminated with concurrent IGF1R activation. Transcription of FOXO3a-regulated TRAIL and PTEN-induced putative kinase-1 (PINK1) was increased with EGFR inhibition in sensitive cell lines; this effect was diminished with IGF1R stimulation. IMPLICATIONS: These data suggest PRAS40 may play an important role in IGF1R-based therapeutic resistance to EGFR inhibition, and this likely occurs via inhibition of FOXO3a-mediated proapoptotic gene transcription.

Perivascular epithelioid cell tumor (PEComa) of the pterygopalatine fossa

Perivascular epithelioid cell tumors (PEComas) are a rare group of mesenchymal tumors associated with tuberous sclerosis. These tumors are typically treated with resection and rarely recur or exhibit malignant behavior. A 78-year-old woman presented with an incidentally discovered pterygopalatine fossa/retroantral mass. Excisional biopsy was performed and revealed pathology consistent with PEComa. Upon review of the literature, there have been 43 reported cases of PEComa of the head and neck. There is only one previously reported case of PEComa in the skull base, and none reported in the pterygopalatine fossa. Of note, the previously reported case of skull base PEComa involved an aggressive tumor with widespread metastasis. Here, we report the first case of a PEComa of the pterygopalatine fossa/retroantral region, which was treated conservatively. This rare pathology should be considered in the differential diagnosis for atypical skull base tumors.

Antitumor effect of insulin-like growth factor-1 receptor inhibition in head and neck squamous cell carcinoma

OBJECTIVES

The insulin-like growth factor-1 receptor (IGF1R) has been implicated in therapeutic resistance in head and neck squamous cell carcinoma (HNSCC), and small molecule tyrosine kinase inhibitors (TKIs) of IGF1R activity may have anticancer activity. Therefore, the relationship between survival and IGF1R expression was assessed for oral cavity (OC) cancer, and the antitumor effects of two IGF1R-TKIs, OSI-906 and BMS-754807, were evaluated in HNSCC cell lines in vitro.

METHODS

Clinical outcome data and tissue microarray immunohistochemistry were used to generate IGF1R expression-specific survival curves. Immunoblot, alamarBlue proliferation assay, trypan blue exclusion viability test, clonogenic assay, flow cytometry, and reverse phase protein array (RPPA) were used to evaluate in vitro responses to IGF1R-TKIs.

RESULTS

For patients with stage III/IV OCSCC, higher IGF1R expression was associated with poorer overall 5-year survival (P = 0.029). Both BMS-754807 and OSI-906 caused dose-dependent inhibition of IGF1R and Akt phosphorylation and inhibited proliferation; BMS-754807 was more potent than OSI-906. Both drugs reduced HNSCC cell viability; only OSI-906 was able to eliminate all viable cells at 10 μM. The two drugs similarly inhibited clonogenic cell survival. At 1 μM, only BMS-754807 caused a fourfold increase in the basal apoptotic rate. RPPA demonstrated broad effects of both drugs on canonical IGF1R signaling pathways and also inhibition of human epidermal growth factor receptor-3 (HER3), Src, paxillin, and ezrin phosphorylation.

CONCLUSION

OSI-906 and BMS-754807 inhibit IGF1R activity in HNSCC cell lines with reduction in prosurvival and proliferative signaling and with concomitant antiproliferative and proapoptotic effects. Such antagonists may have utility as adjuvants to existing therapies for HNSCC.

LEVEL OF EVIDENCE

NA Laryngoscope, 130:1470-1478, 2020.

Survivin in Insulin-Like Growth Factor-Induced Resistance to Lapatinib in Head and Neck Squamous Carcinoma Cells

Epidermal growth factor receptor (EGFR) inhibitors have limited efficacy in head and neck squamous cell carcinoma (HNSCC) due to various resistance mechanisms, such as activation of the insulin-like growth factor-1 receptor (IGF1R), which initiates pro-survival signaling. Survivin, a member of the inhibitor of apoptosis proteins family, is expressed at relatively high levels in malignant tissues and plays a role in cell division. Expression of survivin in tumors has been shown to correlate with poor prognosis due to chemotherapy resistance and anti-apoptotic behavior. We previously demonstrated that activation of the IGF1R reduces sensitivity to EGFR-tyrosine kinase inhibitors (TKIs) via reduced apoptosis suggesting a role of survivin in this process. This study evaluates the role of survivin in IGF1R-mediated lapatinib resistance. Using HNSCC cell lines FaDu and SCC25, survivin expression increased and lapatinib sensitivity decreased with IGF1R activation. Further, these effects were reversed by the survivin inhibitor YM-155. Conversely, survivin expression and lapatinib sensitivity were unchanged with IGF1R activation in UNC10 cells. YM-155 enhanced the inhibitory effect of lapatinib on UNC10 cells, regardless of activation of the IGF1R. These results demonstrate that enhanced survivin expression correlates with IGF1R-mediated lapatinib resistance in HNSCC cells and suggest that regulation of survivin expression may be a key mechanistic element in IGF1R-based therapeutic resistance. Combinatorial treatment with survivin antagonists and EGFR-TKIs warrants further investigation.

Abstract 1829: PRAS40 as a mediator of insulin-like growth factor-1 receptor-induced resistance to epidermal growth factor receptor inhibition in head and neck cancer

BACKGROUND: Despite the known growth-promoting role of the epidermal growth factor receptor (EGFR) in head and neck squamous cell carcinoma (HNSCC), EGFR tyrosine kinase inhibitors (TKIs) have shown low efficacy in this disease. The insulin-like growth factor-1 receptor (IGF-1R) has been shown to induce resistance to EGFR TKIs in HNSCC predominantly through anti-apoptotic pathways. PRAS40 is an inhibitor of mTOR that ceases inhibition upon phosphorylation by Akt. Phosphorylated PRAS40 in turn inhibits FOXO3a, contributing to an overall pro-survival state. This study evaluates the role of PRAS40 in IGF-1R mediated resistance to EGFR TKIs.

METHODS: In vitro experiments using alamarBlue, CyQuant, reverse phase protein microarray (RPPA), and immunoblot techniques to evaluate protein expression/phosphorylation and correlate with cell physiologic behavior.

RESULTS: Proliferation assays were used to separate 6 HNSCC cell lines into 2 groups: those rescued from EGFR inhibition by IGF-1R activation and those not rescued. RPPA analysis identified a correlation between PRAS40 phosphorylation and rescue status. Immunoblot analysis confirmed the RPPA findings: in rescued cell lines, PRAS40 phosphorylation decreases with EGFR inhibition, but phosphorylation is restored by IGF-1R activation. However, these treatments have little effect on PRAS40 phosphorylation in non-rescued cell lines. In a representative cell line from each group, p70S6K phosphorylation was found to follow this pattern as well, suggesting possible involvement of mTOR in the rescue mechanism. However the addition of temsirolimus, an mTORC1 inhibitor, to treatment with an EGFR TKI was not sufficient to overcome IGF-induced rescue.

CONCLUSIONS: PRAS40 phosphorylation is tightly correlated with IGF1R activation in HNSCC cells that exhibit IGF1R-induced rescue from EGFR TKI treatment. This phenomenon is absent in non-rescued cells, suggesting a potential role for pPRAS40 in IGF1R-based therapeutic resistance. While PRAS40 phosphorylation results in mTOR activation, the inability of mTOR inhibition to overcome IGF-induced rescue from EGFR antagonism suggests an important alternative downstream pathway. One possible mechanism is through inhibition of FOXO3a, a function of pPRAS40 that has been previously reported in other cell types.

Citation Format: Michael I. Dougherty, Christine E. Lehman, Rolando E. Mendez, Linnea E. Taniguchi, Julie Wulfkuhle, Emanuel F. Petricoin, Daniel G. Gioeli, Mark J. Jameson. PRAS40 as a mediator of insulin-like growth factor-1 receptor-induced resistance to epidermal growth factor receptor inhibition in head and neck cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1829.

Effect of Adipose-Derived Stem Cells on Head and Neck Squamous Cell Carcinoma

Objective Patients with head and neck squamous cell carcinoma (HNSCC) have significant wound-healing difficulties. While adipose-derived stem cells (ASCs) facilitate wound healing, ASCs may accelerate recurrence when applied to a cancer field. This study evaluates the impact of ASCs on HNSCC cell lines in vitro and in vivo. Study Design In vitro experiments using HNSCC cell lines and in vivo mouse experiments. Setting Basic science laboratory. Subjects and Methods Impact of ASCs on in vitro proliferation, survival, and migration was assessed using 8 HNSCC cell lines. One cell line was used in a mouse orthotopic xenograft model to evaluate in vivo tumor growth in the presence and absence of ASCs. Results Addition of ASCs did not increase the number of HNSCC cells. In clonogenic assays to assess cell survival, addition of ASCs increased colony formation only in SCC9 cells (maximal effect 2.3-fold, P < .02) but not in other HNSCC cell lines. In scratch assays to assess migration, fluorescently tagged ASCs did not migrate appreciably and did not increase the rate of wound closure in HNSCC cell lines. Addition of ASCs to HNSCC xenografts did not increase tumor growth. Conclusion Using multiple in vitro and in vivo approaches, ASCs did not significantly stimulate HNSCC cell proliferation or migration and increased survival in only a single cell line. These findings preliminarily suggest that the use of ASCs may be safe in the setting of HNSCC but that further investigation on the therapeutic use of ASCs in the setting of HNSCC is needed.