A non-randomized comparison of gemcitabine-based chemoradiation with or without induction chemotherapy for locally advanced squamous cell carcinoma of the head and neck

Gemcitabine-Based Chemoradiation in the Treatment of Locally Advanced Head and Neck Cancer: Systematic Review of Literature and Meta-Analysis

BACKGROUND

Platinum-based concurrent chemoradiation (CCRT) improves locoregional control and overall survival of locoregionally advanced (LA) squamous cell carcinoma of the head and neck (SCCHN) when compared to radiotherapy alone, but this approach is hampered by significant toxicity. Therefore, alternative ways to enhance the radiation effects are worth investigating. Gemcitabine (2',2'-difluorodeoxycytidine), in addition to its activity against a variety of solid tumors, including SCCHN, is one of the most potent radiosensitizers, and it has an overall favorable safety profile. In this paper, the clinical experience with gemcitabine-based chemoradiation in the treatment of patients with LA-SCCHN is reviewed.

METHODS

We conducted a review of the literature on the clinical experience with radiotherapy combined with either single-agent gemcitabine or gemcitabine/cisplatin-based polychemotherapy for the treatment of patients with LA-SCCHN. We also searched abstracts in databases of major international oncology meetings from the last 20 years. A meta-analysis was performed to calculate pooled proportions with 95% confidence intervals (CIs) for complete response rate and grade 3-4 acute mucositis rate.

RESULTS

A total of 13 papers were eligible for the literature review. For schedules using a gemcitabine dose intensity (DI) below 50 mg/m(2) per week, the complete response rate was 86% (95% CI, 74%-93%) with grade 3-4 acute mucositis rate of 38% (95% CI, 27%-50%) and acceptable late toxicity. In one of the studies employing such low DIs, survival data were provided showing a 3-year overall survival of 50%. Compared with DI ≥50 mg/m(2) per week, there was no difference in the complete response rate (71%; 95% CI, 55%-83%; p = .087) but a significantly higher (p < .001) grade 3-4 acute mucositis rate of 74% (95% CI, 62%-83%), often leading to treatment interruptions (survival data provided in 8 studies; 3-year overall survival, 27%-63%). Late toxicity comprising mainly dysphagia was generally underreported, whereas information about xerostomia and skin fibrosis was scarce.

CONCLUSION

This review highlights the radiosensitizing potential of gemcitabine and suggests that even very low dosages (less than 50 mg/m(2) per week) provide a sufficient therapeutic ratio and therefore should be further investigated. Refinements in radiation schemes, including intensity-modulated radiation therapy, in combination with low-dose gemcitabine and targeted agents, such as cetuximab, are currently being investigated.

IMPLICATIONS FOR PRACTICE

Cisplatin-based concurrent chemoradiation (CCRT) has become the standard treatment of locally advanced head and neck cancer (LAHNC). This approach is hampered by significant toxicity. This paper reviews the studies using gemcitabine as an alternative radio-sensitizer for CCRT in patients with LAHNC. In this capacity, despite its mild intrinsic toxicity, gemcitabine comes with high rates of severe mucositis when used in dosages exceeding 50 mg/m(2) per week. CCRT with low-dose gemcitabine provides a sufficient therapeutic ratio, combining clinical activity, similar to the higher-dose regimens, with lower toxicity. Further investigation is warranted.

Phase I trial of radiotherapy concurrent with twice-weekly gemcitabine for head and neck cancer: translation from preclinical investigations aiming to improve the therapeutic ratio

BACKGROUND

Once-weekly gemcitabine concurrent with radiotherapy was highly effective in the treatment of head and neck cancer (HNC) but limited by high mucosal toxicity. Pre-clinical investigations suggested that delivering gemcitabine at substantially lower doses twice weekly during radiotherapy improved the therapeutic ratio. We sought to translated these preclinical findings to a phase I trial.

METHODS

Twenty-five patients with non-resectable HNC were scheduled to receive gemcitabine twice weekly during the last 2 weeks (total 5 infusions) of hyperfractionated radiotherapy delivering 1.2 Gy twice daily to total 76.8 Gy. Tumor biopsies to measure active intracellular (phosphorylated) gemcitabine were planned after the first drug delivery. Patients were assigned to escalating dose cohorts using the Continuous Reassessment Method.

RESULTS

Twenty-one patients evaluable for toxicity were divided into cohorts receiving twice weekly treatment with 10, 20, 33, or 50 mg/m(2) gemcitabine. Dose-limiting toxicity was grade 3-4 confluent mucositis/pharyngitis, and the maximally tolerated dose (MTD) was 20 mg/m(2). Median survival was 20 months, with no difference between cohorts receiving lower (10, 20 mg/m(2)) or higher (33, 50 mg/m(2)) gemcitabine doses. Tumor biopsies after the first drug delivery showed only a minority of tumor cells in the specimens.

CONCLUSION

These findings validate preclinical models that show that gemcitabine is radiation sensitizer at doses far below those used for systemic chemotherapy. However, the improvement in the therapeutic ratio predicted from the preclinical study did not translate into a substantial relative increase in the MTD of the drug in the clinical phase I trial.

Gemcitabine-based induction chemotherapy and concurrent with radiation in advanced head and neck cancer

To evaluate the efficacy and toxicity of gemcitabine-based induction chemotherapy followed by concurrent gemcitabine and radiotherapy in advanced squamous cell carcinoma of head and neck. A total of 28 patients with locally advanced squamous cell carcinoma of the head and neck were enrolled. All patients were treated with 2 cycles of induction gemcitabine 1 gm/m(2) on days 1 and 8 plus cisplatin 75 mg/m(2)no day 1 of a 3-week cycles followed by conventionally fractionated radiotherapy to 70 Gy in 35 fractions concurrent with weekly gemcitabine 100 mg/m(2) within 2 h before radiotherapy. Median age was 56.5 years (range, 30-68). Four patients (14.3 %) achieved complete response (CR) and 19 patients (67.9 %) had partial response (PR) after induction chemotherapy. After concurrent chemo-radiotherapy, we reported 17 (60.7 %) CR and 8 (28.6 %) PR. Median loco-regional recurrence-free survival, progression-free survival, and overall survival were 17, 12.5, and 21 months, respectively. Performance status, T stage, AJCC stage, and response to chemo-radiation were found to have significant impact on survival. Acute grade 3 toxicity of concurrent chemo-radiation included 35.7 % dysphagia, 25 % stomatitis, and 10.7 % neutropenia, whereas late grade 3 toxicity included xerostomia in 7.1 % and stomatitis in 3.6 % of patients. Gemcitabine-based induction and concurrent chemo-radiotherapy is effective treatment for locally advanced squamous cell carcinoma of head and neck with acceptable and manageable toxicity. Optimizing dose and schedule of gemcitabine-based chemo-radiation is still needed.

Intensity-modulated radiotherapy in patients with head and neck cancer: a European single-centre experience

OBJECTIVE

The purpose of this study was to analyse retrospectively the intensity-modulated radiotherapy (IMRT) results in patients with head and neck cancer (HNC) treated between November 2003 and June 2007.

METHODS

Patients with early and locoregionally advanced HNC were treated with inverse-planned step-and-shoot IMRT. The prescribed dose varied from 66 Gy to 70 Gy in those receiving IMRT as definitive treatment and from 60 Gy to 70 Gy in the post-operative setting. IMRT was given alone, after induction chemotherapy (ICT), with concomitant chemotherapy (CRT) or with both. Acute and late toxicities are reported; locoregional control (LRC), locoregional relapse-free survival (LRRFS) and overall survival (OS) were calculated from the start of radiation.

RESULTS

IMRT was used in 78 patients (48 as definitive treatment, 30 post-operatively), of whom 20 also received ICT and 35 CRT. Three patients stopped IMRT early, one for toxicity (mucosa). Acute toxicity scoring revealed 5 cases (6%) of severe skin toxicity and 65 cases (83%) of severe mucosal toxicity. After a median follow-up of 18.7 months, late toxicities included xerostomia (44%), loss of taste (14%) and fibrosis of the neck (9%). 16 patients had died, of whom 10 due to tumour recurrence/progression and 2 due to treatment (but not IMRT related). The LRC, LRRFS and OS at 3 years are 66.1%, 48.5% and 60.3% in the definitive IMRT group and 85.4%, 82.5% and 85.9% in the post-operative setting, respectively.

CONCLUSION

We consider IMRT for locoregional HNC feasible not only as a single modality but also after surgery, after induction chemotherapy and concurrently with chemotherapy.

Difluorodeoxyuridine plasma concentrations after low-dose gemcitabine during chemoradiation in head and neck cancer patients

PURPOSE

The aim of this study was to investigate whether relevant plasma levels of dFdU could be detected during concurrent chemoradiation (CRT) with low doses of dFdC administered in patients with head and neck cancer and to assess the toxicity related to dose.

METHODS

dFdC was administered at doses of 5 mg/m² twice weekly or 10, 50, or 100 mg/m² weekly. Plasma concentrations of dFdU were determined daily for 7 days after the first administration and before each administration, thereafter. A high-performance liquid chromatographic method was used. During CRT, skin and mucosal toxicity were scored weekly according to the RTOG toxicity scoring system.

RESULTS

Eight patients were sampled at the 10-50 mg/m² dose and nine at the 5-100 mg/m² dose. dFdU levels were in the micromolar range, inducing RS in vitro. There was a strong correlation between the area under the curve of dFdU and the dose of dFdC (r = 0.803, P < 0.001) and a weak correlation between trough concentrations and total dose of dFdC (r = 0.408, P = 0.017). Duration of severe mucositis correlated with dFdC dose.

CONCLUSIONS

During CRT with 10-100 mg/m(2) of dFdC weekly or 5 mg/m(2) twice weekly, dFdU remains detectable at potentially radiosensitizing concentrations.