Multiagent Concurrent Chemoradiotherapy for Locoregionally Advanced Squamous Cell Head and Neck Cancer: Mature Results From a Single Institution

Phase II study of low-dose paclitaxel and cisplatin in combination with split-course concomitant twice-daily reirradiation in recurrent squamous cell carcinoma of the head and neck: results of Radiation Therapy Oncology Group Protocol 9911

PURPOSE

Recurrent squamous cell carcinoma of the head and neck (SCCHN) or new second primary tumor (SPT) in a previous radiation field, if not curable by surgery or radiation, is almost always fatal. Chemotherapy alone yields a median survival time (MST) of no more than 10 months and 1-year overall survival (OS) of 35% at best. Concurrent reirradiation and chemotherapy is an alternative strategy.

PATIENTS AND METHODS

Eligibility for Radiation Therapy Oncology Group (RTOG) protocol 9911 stipulated recurrent SCCHN or SPT in a previous radiation field. Patients received twice-daily radiation (1.5 Gy per fraction bid x 5 days every 2 weeks x4), plus cisplatin 15 mg/m2 intravenously (IV) daily x 5 and paclitaxel 20 mg/m2 IV daily x 5 every 2 weeks x4. Granulocyte colony-stimulated factor was administered days 6 through 13 of each 2-week cycle.

RESULTS

One hundred five patients were enrolled from March 2000 through June 2003; 23% had SPT. Oropharynx (40%) and oral cavity (27%) were the predominant primary sites. Median prior radiation dose was 65.4 Gy. Seventy-four percent of patients completed chemotherapy. Grade 4 or worse acute toxicity occurred in 28%, grade 4 or worse acute hematologic toxicity in 21%. Eight treatment-related deaths (8%) occurred: five in the acute setting, three late (including two carotid hemorrhages). MST was 12.1 months, with estimated 1- and 2-year OS rates of 50.2% and 25.9%.

CONCLUSION

Despite a high incidence of grade 5 toxicity, 1- and 2-year OS rates for split-course bid radiation therapy and concurrent cisplatin/paclitaxel exceed results generally seen with chemotherapy alone.

Evidence-based radiation oncology in head and neck squamous cell carcinoma

BACKGROUND AND PURPOSE

Historically, radiation therapy (RT) has been an available treatment option for patients with early resectable head and neck squamous cell carcinoma (HNSCC) and the sole therapy for those with unresectable or inoperable disease. Recently, four noteworthy strategies have emerged for the improvement of therapeutic outcome in the curative treatment of HNSCC: they include the development of altered fractionation radiotherapy, integration of chemotherapy with radiotherapy, incorporation of intensity-modulated radiotherapy and the introduction of targeted biological therapy. These strategies are briefly reviewed in an effort to help interpret evidence-based data and to facilitate clinical-decision making in a clinical context.

MATERIALS AND METHODS

For patients with early stage HNSCC no level 1 study exists in which radiation therapy is compared with conservative surgery for the evaluation of local control or survival. Only evidence from prospective and retrospective cohort studies is available to evaluate the role external radiotherapy and/or brachytherapy currently play in limited disease. For patients with locally advanced HNSCC the recommendations to address the questions about better treatment in resectable and unresectable tumors are based on more than 100 randomized Phase III trials included in six meta-analyses on chemo-radiotherapy and/or altered fractionation. Data from phase II trials and cohort studies help interpret the advances in intensity-modulated radiotherapy.

RESULTS

External radiotherapy and/or brachytherapy are crucial treatment options in patients with early stage HNSCC. For patients with locally advanced HNSCC, where outcome with conventional radiotherapy is poor, meta-analyses and collective data showed that loco-regional control may be improved at high level of evidence by altered fractionation radiotherapy, chemo-radiotherapy with concomitant approach or association of selected hypoxic cell radiosensitizer with radiotherapy. For these patients, overall survival may be improved at high level of evidence by concomitant chemo-radiotherapy or hyperfractionated RT delivered with increased total dose. Also EGFR-inhibitors (cetuximab)-radiotherapy strategy offers at a lower level of evidence better loco-regional control and overall survival than radiotherapy alone. Chemo-radiotherapy programs can achieve an improved larynx-function preservation program without the risk of overall survival reduction, for patients with larynx or hypopharynx tumors who are candidates to radical surgery followed by radiotherapy. Recently, strong evidence for an improved outcome for high-risk resected patients has been shown by the use of adjuvant concomitant chemo-radiotherapy. Despite improved results, a higher severe toxicity has been largely evidenced with concomitant chemo-radiotherapy by reducing the gain in the therapeutic index with new treatment strategies. Three-dimensional conformal radiotherapy is the minimal standard of technique in HNSCC: however, as advances are promising, intensity-modulated radiotherapy should be largely implemented.

CONCLUSIONS

Stepwise improvements in HNSCC non-surgical therapy have shown favorable impact on loco-regional control and overall survival. However, despite hundreds of clinical trials in patients with advanced disease, there is no absolute consensus about patient selection for altered fractionation regimens, type of chemo-radiotherapy association, radiation or chemotherapy dose schedule. Nevertheless, many well-conducted clinical studies have expanded therapy options besides standard radiotherapy and have contributed to defining the evolving standard of care for patients with HNSCC.

The chemoradiation paradigm in head and neck cancer

In this article, we use the example of head and neck cancer to show how concurrent chemoradiotherapy is used to treat a cancer where locoregional control is central for treatment success. The advent of concurrent chemoradiation has significantly contributed to the curability of head and neck cancer, including locoregionally advanced disease. Preserving organ function and reducing toxic effects are increasingly the focus of clinical trials. We review the available chemoradiotherapy platforms used for head and neck cancer, with initial discussions focused on single-agent cytotoxic-based regimens. We then assess the literature on multiagent-based regimens and include a discussion of the integration of novel agents, such as EGFR inhibitors, and antiangiogenic drugs into treatment platforms. Although single-agent cisplatin-based chemoradiotherapy is still widely used as a standard therapy, we propose that evidence increasingly shows that multiagent-based chemoradiotherapy, and EGFR-inhibitor-based treatments, offer distinct advantages. We provide guidance for clinicians based on current clinical trial evidence on how to choose appropriate treatment platforms for their patients.

Structural characterization of N-linked oligosaccharides on monoclonal antibody cetuximab by the combination of orthogonal matrix-assisted laser desorption/ionization hybrid quadrupole-quadrupole time-of-flight tandem mass spectrometry and sequential enzymatic digestion

Cetuximab is a novel therapeutic monoclonal antibody with two N-glycosylation sites: a conserved site in the CH2 domain and a second site within the framework 3 of the variable portion of the heavy chain. The detailed structures of these oligosaccharides were successfully characterized using orthogonal matrix-assisted laser desorption/ionization hybrid quadrupole-quadrupole time-of-flight mass spectrometry (oMALDI Qq-TOF MS) and tandem mass spectrometry (MS/MS) in combination with exoglycosidase digestion. The N-linked oligosaccharides were released by treatment with N-glycanase F, reductively aminated with anthranilic acid, and fractionated by normal phase high-performance liquid chromatography (NP-HPLC). The fluorescent-labeled oligosaccharide pool and fractions were analyzed by oMALDI Qq-TOF MS and MS/MS in negative ion mode. Each fraction was further digested with an array of exoglycosidase mixtures, and subsequent MALDI TOF MS analysis of the resulting products yielded information about structural features of the oligosaccharide. The combined data revealed the presence of 21 distinct oligosaccharide structures in cetuximab. These oligosaccharides differ mainly in degree of sialylation with N-glycolyl neuraminic acid and extent of galactosylation (zero-, mono-, di-, and alpha(1-3)-galactosidase). The individual oligosaccharides were further assigned to the specific sites in the Fab and Fc regions of the antibody. This study represents a unique approach in that MS/MS data were used to identify and confirm the oligosaccharide structures of a protein.

Planned Neck Dissection after Weekly Docetaxel and Concurrent Radiotherapy for Advanced Oropharyngeal Cancer

Small oropharyngeal carcinomas with advanced neck metastases (stage N2 or greater) are common. Patients with small T with large N oropharyngeal carcinoma have high rates of local control but lower rates of regional control when treated with chemoradiotherapy. Clinical assessment after chemoradiotherapy cannot ensure the absence of neck disease. In the last 5 years, we have treated patients with T1-2 with N2-3 oropharyngeal carcinoma with weekly docetaxel radiotherapy followed by planned neck dissection (PND). Our objectives were to clarify the pathologically complete response (CR) rate of neck metastasis after weekly docetaxel radiotherapy, to identify the clinical predictor of residual neck disease, and to determine the mobidity of planned neck dissection. After chemoradiotherapy, all 12 patients had a complete response at the primary site. We conducted 15 neck dissections. Of these, 6 (40%) had positive nodes. The pathological CR rate of neck metastasis was 58.3%, whereas overall 2-year neck control rate was 91.7%. These findings lend support to the role of PND after chemoradiotherapy in N2-3 neck disease. After chemoradiotherapy, clinical parameters including TN status, feasibility of chemoradiotherapy, largest lymph node size or size reduction in MRI, did not identify patients with residual neck disease. We conducted selective neck dissection (SND) in 80% of patients. SNI) as PND appears to be appropriate in this group of patients because of the low incidence of complications. A further cohort study including the comparison of PND nonenforcement group is necessary to clarify the validity of the addition of PND in weekly docetaxel radiotherapy.

The role of interstitial brachytherapy with salvage surgery for the management of recurrent head and neck cancers

BACKGROUND

The role of interstitial brachytherapy (IBT) in the salvage surgical management of regional lymphatic metastases for head and neck cancer has not been defined to date. To further explore its therapeutic benefit in the management of head and neck squamous cell carcinoma, the authors reviewed their experience utilizing IBT at the M. D. Anderson Cancer Center.

METHODS

A retrospective chart review of all patients who were received IBT for cervical recurrences of head and neck cancer was undertaken. Twenty-two patients were identified; all patients underwent neck dissection and intraoperative placement of afterloading catheters as part of the salvage treatment. Soft tissue reconstruction was performed when necessary. The duration and dosage of salvage brachytherapy was reviewed, and the overall disease-free survival rates were determined.

RESULTS

All patients had been treated with external beam radiation therapy prior to recurrence, with an average dose of 65 grays (Gy), and 46% of patients had undergone prior neck dissection. The median time to regional recurrence after definitive treatment was 30 months. Soft tissue coverage of the surgical bed with a muscle flap, most commonly a pectoralis major flap, was performed in 19 of 22 patients. The median IBT dose was 60 Gy over a total duration of 4 days. Postoperative complications were few, and there were no perioperative deaths. Recurrences in the reirradiated necks occurred in 27% of patients.

CONCLUSIONS

Regional recurrences are common after multimodality treatment for head and neck cancer and are challenging to manage. Although its role has not been defined clearly, salvage neck dissection with IBT is beneficial in the management of recurrent lymphatic metastases of upper aerodigestive tract carcinomas.

Does induction chemotherapy have a role in the management of locoregionally advanced squamous cell head and neck cancer?

The use of systemic chemotherapy before definitive locoregional management, or induction chemotherapy, has been a theoretically attractive and well-studied approach in the management of squamous cell head and neck cancer. Although a decrease in distant metastases has frequently been observed, an improvement in survival from induction has been difficult to demonstrate. When chemotherapy and radiation are used concomitantly, however, an improvement in both survival and locoregional control can be identified, and this has led to the adoption of concurrent chemoradiotherapy as a standard of care for these patients. With this improvement in locoregional control, distant metastases have become a more frequently recognized cause of treatment failure, suggesting that an intervention, such as induction chemotherapy, directed at improving distant control might now be of some importance in improving overall treatment success. The recent development of taxane-containing, three-drug induction regimens that are capable of producing significantly better response rates than the older cisplatin and fluorouracil combination has also raised the possibility of a new and more important role for induction. The results of phase II investigations using this kind of a sequential schedule of induction chemotherapy followed by concurrent chemoradiotherapy have been encouraging, and phase III trials are now underway. This treatment approach remains investigational however, and these phase III studies are critical. The current randomized trials are reviewed and discussed.

Reassessment of the role of induction chemotherapy for head and neck cancer

Head and neck cancers are a complex group of diseases defined by variations in histological features, anatomical location, and cause. Once the realm of surgeons and radiation oncologists, the treatment of locally advanced disease now involves medical oncologists. Major developments include primary chemoradiotherapy for unresectable disease and organ preservation, the addition of chemotherapy to adjuvant radiotherapy, improvement in surgical and radiation techniques, and biological therapies. Concomitant chemoradiotherapy consistently improves locoregional control. However, control of distant metastases is poor, resulting in an increasing proportion of deaths from systemic recurrence. Given this shift in site of recurrence, therapeutic strategies to suppress distant metastases may be the next goal for further improvement of survival. One approach that merits reassessment is the use of induction chemotherapy in the setting of locally advanced disease--both resectable and unresectable. In this review we summarise data for the use of induction chemotherapy to define better which patients will likely benefit from this approach now and which questions are important in the design of future clinical trials.

Concurrent Chemoradiotherapy for Locally Advanced, Nonmetastatic, Squamous Carcinoma of the Head and Neck: Consensus, Controversy, and Conundrum

Radiotherapy and concurrent chemotherapy (CRT) is superior to radiotherapy alone for the treatment of locally advanced, nonmetastatic squamous carcinoma of the head and neck (HNC). Three issues affect the use of CRT as primary treatment for advanced HNC. The first issue is the definition of advanced stage and the initial therapeutic choice of surgery or CRT and the role of post-CRT neck dissection. Function preservation considerations should guide the choice between surgery and CRT for patients with resectable disease. Fluorodeoxyglucose–positron emission tomography scanning may identify patients who require adjuvant neck dissection. The second issue is optimization of radiotherapy and chemotherapy schedules. Ideally, concurrent chemotherapy should be incorporated into radiotherapy (RT) regimens that would constitute optimal therapy were RT to be administered as single-modality treatment. Modified fractionation schemes constitute optimal single-modality RT. Platinum schedules other than bolus dosing every 3 to 4 weeks are effective and may be less toxic. The third issue is integration of biologically targeted therapy into CRT treatment programs. Epidermal growth factor receptor blockade enhances the effectiveness of RT alone. Its role and that of angiogenic blockade in CRT are under investigation.