Interventions for the treatment of oral cavity and oropharyngeal cancer: chemotherapy

BACKGROUND

Oral cavity and oropharyngeal cancers are the most common cancers arising in the head and neck. Treatment of oral cavity cancer is generally surgery followed by radiotherapy, whereas oropharyngeal cancers, which are more likely to be advanced at the time of diagnosis, are managed with radiotherapy or chemoradiation. Surgery for oral cancers can be disfiguring and both surgery and radiotherapy have significant functional side effects. The development of new chemotherapy agents, new combinations of agents and changes in the relative timing of surgery, radiotherapy, and chemotherapy treatments may potentially bring about increases in both survival and quality of life for this group of patients. This review updates one last published in 2011.

OBJECTIVES

To determine whether chemotherapy, in addition to radiotherapy and/or surgery for oral cavity and oropharyngeal squamous cell carcinoma results in improved overall survival, improved disease-free survival and/or improved locoregional control, when incorporated as either induction therapy given prior to locoregional treatment (i.e. radiotherapy or surgery), concurrent with radiotherapy or in the adjuvant (i.e. after locoregional treatment with radiotherapy or surgery) setting.

SEARCH METHODS

An information specialist searched 4 bibliographic databases up to 15 September 2021 and used additional search methods to identify published, unpublished and ongoing studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) where more than 50% of participants had primary tumours in the oral cavity or oropharynx, and that evaluated the addition of chemotherapy to other treatments such as radiotherapy and/or surgery, or compared two or more chemotherapy regimens or modes of administration.

DATA COLLECTION AND ANALYSIS

For this update, we assessed the new included trials for their risk of bias and at least two authors extracted data from them. Our primary outcome was overall survival (time to death from any cause). Secondary outcomes were disease-free survival (time to disease recurrence or death from any cause) and locoregional control (response to primary treatment). We contacted trial authors for additional information or clarification when necessary.

MAIN RESULTS

We included 100 studies with 18,813 participants. None of the included trials were at low risk of bias.  For induction chemotherapy, we reported the results for contemporary regimens that will be of interest to clinicians and people being treated for oral cavity and oropharyngeal cancers. Overall, there is insufficient evidence to clearly demonstrate a survival benefit from induction chemotherapy with platinum plus 5-fluorouracil prior to radiotherapy (hazard ratio (HR) for death 0.85, 95% confidence interval (CI) 0.70 to 1.04, P = 0.11; 7427 participants, 5 studies; moderate-certainty evidence), prior to surgery (HR for death 1.06, 95% CI 0.71 to 1.60, P = 0.77; 198 participants, 1 study; low-certainty evidence) or prior to concurrent chemoradiation (CRT) with cisplatin (HR for death 0.71, 95% CI 0.37 to 1.35, P = 0.30; 389 participants, 2 studies; low-certainty evidence). There is insufficient evidence to support the use of an induction chemotherapy regimen with cisplatin plus 5-fluorouracil plus docetaxel prior to CRT with cisplatin (HR for death 1.08, 95% CI 0.80 to 1.44, P = 0.63; 760 participants, 3 studies; low-certainty evidence).  There is insufficient evidence to support the use of adjuvant chemotherapy over observation only following surgery (HR for death 0.95, 95% CI 0.73 to 1.22, P = 0.67; 353 participants, 5 studies; moderate-certainty evidence). Among studies that compared post-surgical adjuvant CRT, as compared to post-surgical RT, adjuvant CRT showed a survival benefit (HR 0.84, 95% CI 0.72 to 0.98, P = 0.03; 1097 participants, 4 studies; moderate-certainty evidence). Primary treatment with CRT, as compared to radiotherapy alone,  was associated with a reduction in the risk of death (HR for death 0.74, 95% CI 0.67 to 0.83, P < 0.00001; 2852 participants, 24 studies; moderate-certainty evidence).  AUTHORS' CONCLUSIONS: The results of this review demonstrate that chemotherapy in the curative-intent treatment of oral cavity and oropharyngeal cancers only seems to be of benefit when used in specific circumstances together with locoregional treatment. The  evidence does not show a clear survival benefit from the use of induction chemotherapy prior to radiotherapy, surgery or CRT. Adjuvant CRT reduces the risk of death by 16%, as compared to radiotherapy alone. Concurrent chemoradiation as compared to radiation alone is associated with a greater than 20% improvement in overall survival; however, additional research is required to inform how the specific chemotherapy regimen may influence this benefit.

Single-cycle induction chemotherapy before chemoradiotherapy or surgery in functionally inoperable head and neck squamous cell carcinoma: 10-year results

INTRODUCTION

The response to induction chemotherapy (IC) predicts local control after conservative treatment of laryngeal, meso- and hypopharyngeal head and neck squamous cell carcinoma (HNSCC) and can thus help to avoid surgery. Single-cycle induction chemotherapy may help to maintain a low local recurrence rate while keeping the overall toxicity manageable. However, long-term data on single-cycle IC response by tumor location is lacking.

METHODS

N = 102 patients with functionally inoperable primary HNSCC of the larynx (n = 43), hypopharynx (n = 42) or mesopharynx/tongue (n = 17) received one cycle of docetaxel (75 mg/m², d1) plus cisplatin (30 mg/m², d1-3) or carboplatin (AUC 1.5, d1-3) and a response evaluation 3 weeks later. Responders (≥ 30% tumor size reduction and ≥ 20% SUVmax decrease in ¹⁸F-FDG PET/CT) were recommended chemoradiotherapy (CRT), and non-responders surgery.

RESULTS

The overall response rate was 72.5%. All 74 responders and 10 non-responders received primary CRT, and 18 patients received primary surgery after single-cycle IC. Overall 10-year local recurrence-free survival (LRFS) was 73.7%. Three-year LRFS was 88.2% (mesopharynx/tongue), 88.2% (larynx), and 73.3% (hypopharynx); p = 0.17. 3-year distant metastasis-free survival (DMFS) was 94.1% (mesopharynx/tongue), 88.0% (larynx) and 76.4% (hypopharynx); p > 0.05. This influenced the 3-year cancer-specific survival (CSS) for larynx (91.2%) vs. hypopharynx tumors (60.8%); p = 0.003, but CSS was not different to tumors in the mesopharynx/tongue (81.4%); p > 0.05.

CONCLUSIONS

A single-cycle induction chemotherapy for HNSCC enables surgery plus adjuvant therapy as well as chemoradiotherapy. The long-term local and distant disease control was good but varied between tumors in the larynx and mesopharynx/tongue vs. hypopharynx.

Cisplatin Eligibility Issues and Alternative Regimens in Locoregionally Advanced Head and Neck Cancer: Recommendations for Clinical Practice

Well-designed randomized trials provide the highest level of scientific evidence to guide clinical decision making. In chemoradiotherapy of locally advanced squamous cell carcinoma of the head and neck (SCCHN), data support the use of three cycles of 100 mg/m² cisplatin given every 3 weeks concurrently with conventionally fractionated external beam radiotherapy, although a full compliance with all three cycles is reserved to only about two thirds of initially eligible cases. On an individual patient level, practicing oncologists have to determine whether the patient is a suitable candidate for this treatment or whether contraindications exist. In the latter case, an adequate alternative has to be offered. In this regard, to facilitate triaging of medical information, we reviewed available publications on this topic and prepared practice-oriented recommendations for systemic treatment concurrent to definitive and post-operative radiotherapy. Even if no contraindications for the standard-of-care cisplatin apply, clinicians may opt for alternative regimens by adjusting the peak dose, cumulative dose, or timing of cisplatin. Relative contraindications pose the major issue in clinical practice, as very limited data is available in the literature and final decisions are usually based on an expert opinion or retrospective cohort studies. In the case of absolute interdiction of cisplatin, several alternative regimens incorporating carboplatin, 5-fluorouracil, cetuximab, and docetaxel are available. At the same time, it should be kept in mind that radiotherapy alone represents a viable option with hyperfractionation being particularly beneficial in the definitive management of limited nodal disease. Ideally, all treatment propositions should be discussed within multidisciplinary tumor boards taking into account the patient- and disease-related characteristics as well as local logistics and reimbursement policies.

[Immuno-, radio-, and chemotherapeutic studies in head and neck cancer : Highlights of the ASCO Annual Meeting 2017]

In recent years, immunotherapy has been shown to be a promising approach for the treatment of various tumor entities. Due to further pharmacological developments and new studies, the checkpoint inhibitors have now arrived in the clinic. To date, patients with cancers in the head and neck region have benefited from these agents as part of a palliative therapy. Current clinical trials are testing other indications for the checkpoint inhibitors as monotherapy or in combination with other therapeutic approaches. The following article summarizes the highlights of the American Society of Clinical Oncology (ASCO) Annual Meeting.