Triweekly carboplatin as a potential de-intensification agent in concurrent chemoradiation for early-stage HPV-associated oropharyngeal cancer

Chemoradiation with Cisplatin vs. Carboplatin for Squamous Cell Carcinoma of the Head and Neck (SCCHN)

Cisplatin is the standard for the chemoradiation of squamous cell carcinoma of the head and neck (HNSCC). Many patients cannot receive cisplatin due to impaired renal function. This study investigated carboplatin as an alternative option. In total, 131 patients assigned to two courses of cisplatin (20 mg/m²/d1--5 or 25 mg/m²/d1-4) were matched to 45 patients not suitable for cisplatin and receiving carboplatin (AUC 1.0/d1-5 or AUC 1.5/d1-4). The endpoints included loco-regional control (LRC), metastases-free survival (MFS), overall survival (OS), toxicities, and the completion of chemotherapy. The patients in the carboplatin group were significantly older and had more G3 tumors. Otherwise, the baseline characteristics were balanced. The LRC rates at 2 and 3 years were 77% and 76% in the cisplatin group vs. 69% and 65% in the carboplatin group (p = 0.21). The MFS rates were 83% and 78% vs. 78% and 74% (p = 0.34) and the OS rates 83% and 79% vs. 83% and 75% (p = 0.64), respectively. The outcomes were not significantly different in the subgroups receiving definitive or adjuvant chemoradiation. No significant differences were found regarding toxicities. Non-significantly more patients in the carboplatin group completed their chemotherapy (78% vs. 66%, p = 0.15). Carboplatin was associated with similar outcomes and toxicities as cisplatin, although these patients had worse renal function, more aggressive tumors, and were older. Given the limitations of this study, carboplatin appears an option for patients not suitable for cisplatin.

Treatment de-escalation for HPV+ oropharyngeal cancer: A systematic review and meta-analysis

Human Papillomavirus (HPV) related oropharyngeal carcinoma (OPC) carries a better prognosis compared with HPV-counterparts, thereby pushing the adoption of de-intensification treatment approaches as new strategies to preserve superior oncologic outcomes while minimizing toxicity. We evaluated the effect of treatment de-intensification in terms of overall survival (OS), progression-free survival (PFS), locoregional and distant control (LRC and DM) by selecting prospective or retrospective studies, providing outcome data with reduced intensification versus standard curative treatment in HPV+ OPC patients, with a systematic analysis till September 2020. The primary outcome of interest was OS. Secondary endpoints were PFS, LRC, and DM expressed as HR. A total of 55 studies (from 1393 screened references) were employed for quantitative synthesis for 38 929 patients. Among n = 48 studies with data available, de-intensified treatments reduced OS in HPV+ OPCs (HR = 1.33, 95% CI 1.17-1.52; p < 0.01). In de-escalated treatments, PFS was also decreased (HR = 2.11, 95% CI 1.65-2.69; p < 0.01). Compared with standard treatments, reduced intensity approaches were associated with reduced locoregional and distant disease control (HR = 2.51, 95% CI 1.75-3.59; p < 0.01; and HR = 1.9, 95% CI 1.25-2.9; p < 0.01). Chemoradiation improved survival in a definitive curative setting compared with radiotherapy alone (HR = 1.42, 95% CI 1.16-1.75; p < 0.01). When adjuvant treatments were compared, standard and de-escalation strategies provided similar OS. In conclusion, in patients with HPV+ OPC, de-escalation treatments should not be widely and agnostically adopted in clinical practice, as therein lies a concrete risk of offering a sub-optimal treatment to patients.

Circulating p16-Positive and p16-Negative Tumor Cells Serve as Independent Prognostic Indicators of Survival in Patients with Head and Neck Squamous Cell Carcinomas

BACKGROUND

Decisions regarding the staging, prognosis, and treatment of patients with head and neck squamous cell carcinomas (HNSCCs) are made after determining their p16 expression levels and human papillomavirus (HPV) infection status.

METHODS

We investigated the prognostic roles of p16-positive and p16-negative circulating tumor cells (CTCs) and their cell counts in HNSCC patients. We enrolled patients with locally advanced HNSCCs who received definitive concurrent chemoradiotherapy for final analysis. We performed CTC testing and p16 expression analysis before chemoradiotherapy. We analyzed the correlation between p16-positive and p16-negative CTCs and HPV genotyping, tissue p16 expression status, response to chemoradiotherapy, disease-free survival, and overall survival.

RESULTS

Forty-one patients who fulfilled the study criteria were prospectively enrolled for final analysis. The detection rates of p16-positive (>0 cells/mL blood) and p16-negative (≥3 cells/mL blood) CTCs were 51.2% (n = 21/41) and 70.7%, respectively. The best responses of chemoradiotherapy and the p16 positivity of CTCs are independent prognostic factors of disease progression, with hazard ratios of 1.738 (95% confidence interval (CI): 1.031-2.927), 5.497 (95% CI: 1.818-16.615), and 0.176 (95% CI: 0.056-0.554), respectively. The p16 positivity of CTCs was a prognostic factor for cancer death, with a hazard ratio of 0.294 (95% CI: 0.102-0.852).

CONCLUSIONS

The p16-positive and p16-negative CTCs could predict outcomes in HNSCC patients receiving definitive chemoradiotherapy. This non-invasive CTC test could help stratify the risk and prognosis before chemoradiotherapy in clinical practice and enable us to perform de-intensifying therapies.

Decreasing treatment burden in HPV-related OPSCC: A systematic review of clinical trials

INTRODUCTION

Favorable outcomes are observed after treatment with standard chemoradiotherapy (CRT) for Human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma (OPSCC) patients. The consistent growing interest on treatment-related toxicity burden, potentially jeopardizing survivors' quality of life, led clinicians to investigate possible de-escalation strategies.

MATERIALS AND METHODS

A comprehensive systematic literature search of clinical trials was performed through the EMBASE database to provide an overview of the de-escalation strategies spectrum. Additionally, hand searching and clinicaltrials.gov were also used.

RESULTS

Herein, we report and discuss different approaches to de-escalation of therapy, with respect to both local and systemic strategies.

CONCLUSIONS

Several promising de-escalation experiences have been published. However, while further evidence is awaited, no changes in the management nor deviation from the standard of care should be made outside of clinical trials.

Prognostic impact of retropharyngeal lymphadenopathy in early-stage HPV-associated oropharyngeal cancer: Implications for staging optimization

OBJECTIVES

We analyzed the prognostic impact of retropharyngeal lymphadenopathy (RPL) in stage I node-positive HPV-associated oropharyngeal squamous cell carcinoma (OPSCC).

MATERIALS AND METHODS

We performed a centralized and blinded radiographic review of the pre-treatment images of 234 consecutive patients with AJCC 8th edition stage I cT1-2N1 HPV-associated OPSCC treated with definitive chemoradiation from 2006 to 2016. Five-year disease control and survival outcomes were reported. The prognostic significance of RPL was evaluated through multivariable analysis adjusting for age, smoking history (<10 vs. >10 pack-years), and systemic regimen received.

RESULTS

Median follow-up for surviving patients was 49 months (range: 16-121). RPL was associated with increased locoregional recurrence (LRR) (17.0% v. 3.4%, p = 0.01) and distant metastasis (DM) (29.1% v. 5.9%, p = 0.001) and inferior progression-free survival (PFS) (55.6% v. 88.2%, p < 0.001) and overall survival (OS) (60.6% v. 91.2%, p < 0.001). In stage I patients who did not receive high-dose cisplatin (HDC), RPL was associated with worse LRR (p = 0.04), DM (p = 0.03), PFS (p < 0.001), and OS (p < 0.001), whereas in those who did receive HDC, RPL was only associated with increased DM (p = 0.002) and inferior PFS (p = 0.04).

CONCLUSION

This study suggests that RPL portends a poor prognosis in stage I node-positive HPV-associated OPSCC. The negative impact on LRR may have been mitigated by receipt of HDC. Outcomes of stage I disease with RPL were comparable to historical reports of patients with more advanced-stage disease. Incorporation of RPL into future disease staging should be considered in order to optimize risk-stratification and exclude unsuitable candidates from treatment de-intensification efforts.

Oropharyngeal Squamous Cell Carcinoma in 390 Patients: Analysis of Clinical and Histological Criteria Which Significantly Impact Outcome

This study evaluates the prognostic impact of several factors in oropharyngeal squamous cell carcinoma (OPSCC), controlling for human papillomavirus (HPV)-associated tumors and stage (American Joint Committee on Cancer 8th edition). All patients in Southern California Permanente Medical Group diagnosed with OPSCC between 2006 and 2012 tested for p16 immunohistochemistry were included. Review of all pathology materials was combined with central p16 testing. Multivariable analyses were performed. The cohort of 390 patients included 342 p16-positive and 48 p16-negative tumors. For all-comers, on univariate analysis, the following factors, when present, were associated with improved patient survival: p16-positive tumor (n = 324, p < 0.001); crypt versus surface tumor location (n = 312, p = 0.004); nonkeratinizing type (n = 309, p < 0.0001); nonkeratinizing with maturation type (n = 37, p < 0.0001); basaloid pattern (n = 284, p = 0.005); and a broad, pushing border of infiltration (n = 282, p = 0.004). Inferior survival outcomes were observed with: age ≥ 55 years (p < 0.0001); ≥ 10 pack-year smoking history (n = 183, p = 0.003); increasing tumor stage (p < 0.0001); overt radiographic extranodal extension (ORENE) (n = 58, p < 0.0001); low level IV/Vb lymph node involvement (n = 45, p = 0.0002); a jagged pattern of infiltration (n = 76, p = 0.0004); tumor ulceration (n = 76, p = 0.0004); absent lymphocytic infiltrate (p < 0.0001); and concurrent dysplasia (n = 125, p = 0.009). On multivariable analysis, accounting for patient age, smoking history ≥ 10 pack-years, and TNM stage, for patients with p16-positive disease, advanced TNM stage (p = 0.007), the presence of ORENE (p = 0.0002), and low-neck lymphadenopathy (p = 0.0001) were independent negative prognostic factors for disease free survival (DFS). Older age (p < 0.0001), smoking history ≥ 10 pack-years (p = 0.02), advanced TNM stage (p = 0.0002), ORENE (p = 0.004), and low-neck lymphadenopathy (p = 0.002) were independent negative prognostic factors for OS. Among patients with p16-positive OPSCC, older age, smoking history, advanced stage, ORENE, and low-neck lymphadenopathy were significant negative prognostic factors for DFS and/or OS. Further refinement of staging to incorporate additional lymph node findings may be warranted.