Five compared with six fractions per week of conventional radiotherapy of squamous-cell carcinoma of head and neck: DAHANCA 6 and 7 randomised controlled trial

Development of a multivariable normal tissue complication probability (NTCP) model for tube feeding dependence after curative radiotherapy/chemo-radiotherapy in head and neck cancer

BACKGROUND AND PURPOSE

Curative radiotherapy/chemo-radiotherapy for head and neck cancer (HNC) may result in severe acute and late side effects, including tube feeding dependence. The purpose of this prospective cohort study was to develop a multivariable normal tissue complication probability (NTCP) model for tube feeding dependence 6 months (TUBEM6) after definitive radiotherapy, radiotherapy plus cetuximab or concurrent chemoradiation based on pre-treatment and treatment characteristics.

MATERIALS AND METHODS

The study included 355 patients with HNC. TUBEM6 was scored prospectively in a standard follow-up program. To design the prediction model, the penalized learning method LASSO was used, with TUBEM6 as the endpoint.

RESULTS

The prevalence of TUBEM6 was 10.7%. The multivariable model with the best performance consisted of the variables: advanced T-stage, moderate to severe weight loss at baseline, accelerated radiotherapy, chemoradiation, radiotherapy plus cetuximab, the mean dose to the superior and inferior pharyngeal constrictor muscle, to the contralateral parotid gland and to the cricopharyngeal muscle.

CONCLUSIONS

We developed a multivariable NTCP model for TUBEM6 to identify patients at risk for tube feeding dependence. The dosimetric variables can be used to optimize radiotherapy treatment planning aiming at prevention of tube feeding dependence and to estimate the benefit of new radiation technologies.

T3-T4 laryngeal cancer in The Netherlands Cancer Institute; 10-year results of the consistent application of an organ-preserving/-sacrificing protocol

BACKGROUND

Both organ-preserving concurrent (chemo)radiotherapy ((C)RT) and organ-sacrificing surgery (total laryngectomy) are used for treatment of advanced laryngeal cancer. The purpose of this study was to present the assessment of our treatment protocol for T3 (C)RT and T4 disease (total laryngectomy + postoperative RT).

METHODS

We conducted a retrospective cohort study in 182 consecutive patients (1999-2008). The primary outcome was overall survival (OS) in relation to stage and treatment.

RESULTS

One hundred two patients received RT (82.4% T3), 20 patients CRT (60.0% T3), and 60 patients total laryngectomy + RT (91.7% T4). Five-year OS: T3 52%, T4 48%, for RT 50%, for CRT 43%, and for total laryngectomy + RT 52%. Five-year laryngectomy-free interval was 72% after RT, and 83% after CRT.

CONCLUSION

There were no differences in survival according to T classification or treatment modality. Because the majority of T3 laryngeal cancers were treated with (C)RT and the majority of T4 with total laryngectomy + RT, this gives food for thought on whether the present protocol for T3 laryngeal cancer is optimal.

A multi-institution pooled analysis of gastrostomy tube dependence in patients with oropharyngeal cancer treated with definitive intensity-modulated radiotherapy

BACKGROUND

Severe swallowing dysfunction necessitating enteral support is a well known late sequela of nonsurgical therapy for oropharyngeal cancer, but its incidence after intensity-modulated radiotherapy has not been quantified comprehensively outside of small single-institution series.

METHODS

This was a multi-institution, institutional review board-approved, retrospective study. Consecutive patients with oropharyngeal squamous cell carcinoma who had received definitive intensity-modulated radiotherapy from 1998 to 2011 were identified from 3 academic centers.

RESULTS

In total, 2315 patients were included. The American Joint Committee on Cancer staging distribution was as follows: stage I, 2.1%; stage II, 4.4%; stage III, 14.7%; and stage IV, 77.3%. Among 1459 patients (63%) who received a gastrostomy tube (g-tube), placement was prophylactic in 52% and reactive in 48%. Among patients with stage III and IV disease, 58% received concurrent chemotherapy. The median follow-up was 43.7 months (range, 0.1-164 months). The g-tube dependence rate was 7% at 1 year and 3.7% at 2 years. Among 1238 patients with stage III and IV disease who received concurrent chemotherapy, the 1-year and 2-year rates of g-tube dependence were 8.6% and 4.4%, respectively. The 1-year g-tube dependence rate was 5% for patients with stage I and II disease; 5.2% for patients with stage III and IV, T1-T2/N0-N2 disease; and 10.1% for patients with stage III and IV, T3-T4 or N3 disease. On multivariate analysis, advanced age (odds ratio [OR], 1.066; P<.001), greater number of smoking pack-years (OR, 1.008; P=.04), advanced N-category (OR, 1.13; P=.049), and receipt of cytotoxic chemotherapy (OR, 2.26; P=.02) were predictive of g-tube dependence at 1 year.

CONCLUSIONS

This multi-institution series of 2315 patients treated at 3 institutions demonstrates that modern nonsurgical therapy for oropharyngeal cancer is associated with a low rate of long-term g-tube dependence.

Altered fractionation schedules in radiation treatment: a review

Conventionally fractionated radiotherapy is delivered in 1.8- to 2.0-Gy fractions. With increases in understanding of radiation and tumor biology, various alterations of radiotherapy schedules have been tested in clinical trials and are now regarded by some as standard treatment options. Hyperfractionation is delivered through a greater number of smaller treatment doses. Accelerated fractionation decreases the amount of time over which radiotherapy is delivered typically by increasing the number of treatments per day. Hypofractionation decreases the number of fractions delivered by increasing daily treatment doses. Furthermore, many of these schedules have been tested with concurrent chemotherapy regimens. In this review, we summarize the major clinical studies that have been conducted on altered fractionation in various disease sites.

The clinical importance of assessing tumor hypoxia: relationship of tumor hypoxia to prognosis and therapeutic opportunities

Tumor hypoxia is a well-established biological phenomenon that affects the curability of solid tumors, regardless of treatment modality. Especially for head and neck cancer patients, tumor hypoxia is linked to poor patient outcomes. Given the biological problems associated with tumor hypoxia, the goal for clinicians has been to identify moderately to severely hypoxic tumors for differential treatment strategies. The "gold standard" for detecting and characterizing of tumor hypoxia are the invasive polarographic electrodes. Several less invasive hypoxia assessment techniques have also shown promise for hypoxia assessment. The widespread incorporation of hypoxia information in clinical tumor assessment is severely impeded by several factors, including regulatory hurdles and unclear correlation with potential treatment decisions. There is now an acute need for approved diagnostic technologies for determining the hypoxia status of cancer lesions, as it would enable clinical development of personalized, hypoxia-based therapies, which will ultimately improve outcomes. A number of different techniques for assessing tumor hypoxia have evolved to replace polarographic pO2 measurements for assessing tumor hypoxia. Several of these modalities, either individually or in combination with other imaging techniques, provide functional and physiological information of tumor hypoxia that can significantly improve the course of treatment. The assessment of tumor hypoxia will be valuable to radiation oncologists, surgeons, and biotechnology and pharmaceutical companies who are engaged in developing hypoxia-based therapies or treatment strategies.

Consequences of tumor planning target volume reduction in treatment of T2-T4 laryngeal cancer

Background and purpose

Since lymph nodes volumes are generally four times the volume of the primary PTV, the advantage of using tight margins around the primary PTV is not clear. Therefore treatment margins of T2-T4 laryngeal carcinoma for IMRT are generally chosen in such a way that the PTV is comparable to that in conventional radiotherapy. The aim of this study is to quantify the effect of volume reduction of the primary PTV of T2-T4 laryngeal carcinoma with regard to late toxicity despite elective irradiation of lymph node levels II to IV.

Methods

Two treatment plans based on conservative (GTV-PTV = 15 mm and 20 mm cranial), and on evidence-based tight margins (GTV-PTV = 8 mm) were calculated for 16 patients. Toxicity effects were estimated based on the dose distributions.

Results

Compared to conservative margins, using tight margins resulted in: 1) significant reduction of the normal tissue complication probability (NTCP) for swallowing muscles and submandibular glands, 2) significant reduction of the mean dose in all organs at risk (OAR), 3) a mean dose smaller than 60 Gy for all OARs except for the laryngeal cartilages. When the lymph node levels II to IV were prescribed with an elective dose, an NTCP reduction of 53% for the swallowing muscles and of 23% for the submandibular glands was found by using tight instead of conservative margins. When positive nodes were present, NTCP reduction amounted to 29% and 15%, respectively.

Conclusions

There is a potential benefit in realizing evidence-based tight margins for laryngeal cancer patients despite elective irradiation of lymph node levels II to IV.

Organ preservation strategies: Review of literature and their applicability in developing nations

There has been a change in practice in locally advanced laryngopharyngeal cancers toward non-surgical treatment modalities. Although, there have been landmark trials pertinent to organ preservation, their applicability in developing nations is a topic of much debate. The organ preservation concept was based on the findings of pivotal trials by the Veterans Affairs, European Organization for Research and Treatment of Cancer group and Radiation Therapy Oncology Group. Subsequently numerous studies have been designed to evaluate intensification of treatment as well as study toxicity and tolerability. This review critically analyses current evidence for larynx preservation, experience from various centers on organ preservation strategies as well as applicability of these protocols to developing nations.

Strategies for non-resectable head and neck cancer

OPINION STATEMENT

Treatment of unresectable, locally advanced head and neck cancer consists of many different options, all of them based on radiotherapy. The main variable is represented by chemotherapy, i.e., the way in which chemotherapy is combined with radiation. More recently, the combination of cetuximab and radiotherapy emerged as a new treatment opportunity and induction chemotherapy, with the combination of docetaxel, cisplatin, and 5-fluoruracil, gained a renewed interest. Concurrent chemoradiation is based on the most robust evidence and is regarded as the leading standard of care for unresectable locally advanced head and neck cancer. Unfortunately, chemoradiation is hampered by severe toxicity and patients must be selected carefully before treatment. The experience of the staff (medical oncologists, radiation oncologists, and nurses), and in particular its familiarity with toxicity management, as well the structural facilities, play an important role in the final outcome. When the patient is unfit for chemoradiation, or when experienced staff or adequate structures are unavailable, induction chemotherapy, cetuximab and radiotherapy, or radiotherapy alone are all evidence-based alternative options. The choice among them will be based on the clinical condition of the patient, the physician's experience, and the patient's preference. Whatever is the treatment of choice, it is important to involve a multidisciplinary staff in the management of these patients. Indeed, also unresectable patients may require supportive surgical interventions before or during treatment, or removal of residual disease after treatment.

Randomized trial of hyperfractionation versus conventional fractionation in T2 squamous cell carcinoma of the vocal cord (RTOG 9512)

PURPOSE

To compare hyperfractionation versus standard fractionation for T2N0 vocal cord carcinoma in a randomized controlled trial.

METHODS AND MATERIALS

Patients with T2 vocal cord cancer were stratified by substage (T2a vs T2b) and randomly assigned to receive either hyperfractionation (HFX) to 79.2 Gy in 66 fractions of 1.2 Gy given twice a day, or standard fractionation (SFX) to 70 Gy in 35 fractions given once a day. The trial was designed to detect a 55% reduction in the local failure hazard rate with 80% statistical power.

RESULTS

Between April 1996 and July 2003, a total of 250 patients were enrolled. Of 239 patients analyzable for outcomes, 94% were male, 83% had a Karnofsky performance status of 90-100, and 62% had T2a tumor. Median follow-up for all surviving patients was 7.9 years (range, 0.6-13.1 years). The 5-year local control (LC) rate was 8 points higher but not statistically significant (P=.14 for HFX [78%] vs SFX [70%]), corresponding to a 30% hazard rate reduction. The 5-year disease-free survival (DFS) was 49% versus 40% (P=.13) and overall survival (OS) was 72% versus 63% (P=.29). HFX was associated with higher rates of acute skin, mucosal, and laryngeal toxicity. Grade 3-4 late effects were similar with a 5-year cumulative incidence of 8.5% (3.4%-13.6%) after SFX and 8.5% (3.4%-13.5%) after HFX.

CONCLUSIONS

The 5-year local control was modestly higher with HFX compared to SFX for T2 glottic carcinoma, but the difference was not statistically significant. These results are consistent with prior studies of hyperfractionation showing a benefit in local control. Substaging by T2a versus T2b carries prognostic value for DFS and OS. For cost and convenience reasons other altered fractionation schedules have been adopted in routine practice.

Risk-adapted partial larynx and/or carotid artery sparing modulated radiation therapy of glottic cancer

Background

To evaluate outcome in patients with glottic cancer treated with intensity-modulated radiotherapy (IMRT) and to show effectiveness of partial laryngeal- and/or carotid artery sparing in low to intermediate risk tumors.

Study design

Retrospective analysis.

Material and methods

From 01/2004 to 03/2013 77 consecutive patients presenting with glottic cancer were treated in our department with IMRT as definitive treatment. T-stages distributed as follows: T1: n = 17, T2: n = 24, T3: n = 15, T4: n = 13 and recurrences: 8 patients. Concomitant systemic therapy was applied in 39 patients consisting of either cisplatin or cetuximab.

Results

Mean/median follow-up (FU) time was 32.2/28 months (range: 4–98.7). Three year local control (LC), ultimate LRC and laryngectomy free survival rate was 77%, 92% and 80%, respectively. Three year overall survival of the entire cohort was 81%. Three year local control for T1/T2, T3/T4, and recurred tumors was 95%, 65%, and 38%, respectively. Three year overall survival was 86% for T1-4 stages, 55% for recurred disease, respectively. Partial laryngeal/carotid artery sparing was performed in all T1 patients (n = 17) and 17/22 T2N0 patients. Rate of late sequels was low.

Conclusion

IMRT for glottic cancer shows high control rates. In low to intermediate risk tumors an individualized treatment volume with partial larynx +/- carotid artery sparing is effective and holds the potential to reduce long term toxicity. The therapeutic outcome was not compromised.

Compliance and toxicity of the hypoxic radiosensitizer nimorazole in the treatment of patients with head and neck squamous cell carcinoma (HNSCC)

PURPOSE

To evaluate the compliance and toxicity of the hypoxic radiosensitizer nimorazole in head and neck cancer patients.

METHODS

A retrospective study of patients with head and neck squamous cell carcinoma (HNSCC), treated in Denmark between 1990 and 2013. All patients treated with radical radiotherapy (± chemotherapy) [66-70 Gy; 33-35 fractions; 2 Gy/fraction; 5-6 fractions/week] concomitant with the hypoxic radiosensitizer nimorazole. Nimorazole was administered as oral tablets in doses of approximately 1.2 g/m(2) body surface area in connection with the first of each daily radiation treatment. A second daily dose of 1 g was given in connection with the second radiotherapy fraction in the accelerated fractionation regimen. The compliance was estimated as the percentage of the initially prescribed dose, which was received by each patient. The main side effects were recorded.

RESULTS

A total of 1049 patients were investigated. The tolerance to nimorazole was fair: 58% of patients received the full prescribed total dose. Nausea and vomiting were the major complaints: among the 260 patients with dose reductions due to known side effects, (87%) were due to nausea/vomiting. All side effects ceased when treatment was interrupted, and neither severe nor long lasting side effects were observed. Female patients were significantly more likely to have dose reduction (OR 2.02; 95% CI 1.50-2.70), and nausea/vomiting. Patients aged more than 70 years were significantly more likely to have dose reduction. Patients who received less than 1100 mg/m(2) were significantly less likely to have dose reduction (OR 0.58; CI 0.44-0.78), and nausea/vomiting, compared to those who received 1100-1300 mg/m(2). The tolerance was also less in the group of patients received accelerated chemoradiotherapy (OR 1.70; CI 1.20-2.50) with more association with nausea/vomiting (OR 2.09; CI 1.40-3.10).

CONCLUSION

The compliance to nimorazole is fair, with tolerable acute, but neither persistent nor late, toxicity. It can be administered with chemotherapy and different radiotherapy fractionation schedules.

Final results of local-regional control and late toxicity of RTOG 9003: a randomized trial of altered fractionation radiation for locally advanced head and neck cancer

PURPOSE

To test whether altered radiation fractionation schemes (hyperfractionation [HFX], accelerated fractionation, continuous [AFX-C], and accelerated fractionation with split [AFX-S]) improved local-regional control (LRC) rates for patients with squamous cell cancers (SCC) of the head and neck when compared with standard fractionation (SFX) of 70 Gy.

METHODS AND MATERIALS

Patients with stage III or IV (or stage II base of tongue) SCC (n=1076) were randomized to 4 treatment arms: (1) SFX, 70 Gy/35 daily fractions/7 weeks; (2) HFX, 81.6 Gy/68 twice-daily fractions/7 weeks; (3) AFX-S, 67.2 Gy/42 fractions/6 weeks with a 2-week rest after 38.4 Gy; and (4) AFX-C, 72 Gy/42 fractions/6 weeks. The 3 experimental arms were to be compared with SFX.

RESULTS

With patients censored for LRC at 5 years, only the comparison of HFX with SFX was significantly different: HFX, hazard ratio (HR) 0.79 (95% confidence interval 0.62-1.00), P=.05; AFX-C, 0.82 (95% confidence interval 0.65-1.05), P=.11. With patients censored at 5 years, HFX improved overall survival (HR 0.81, P=.05). Prevalence of any grade 3, 4, or 5 toxicity at 5 years; any feeding tube use after 180 days; or feeding tube use at 1 year did not differ significantly when the experimental arms were compared with SFX. When 7-week treatments were compared with 6-week treatments, accelerated fractionation appeared to increase grade 3, 4 or 5 toxicity at 5 years (P=.06). When the worst toxicity per patient was considered by treatment only, the AFX-C arm seemed to trend worse than the SFX arm when grade 0-2 was compared with grade 3-5 toxicity (P=.09).

CONCLUSIONS

At 5 years, only HFX improved LRC and overall survival for patients with locally advanced SCC without increasing late toxicity.

Development and validation of a prediction model for tube feeding dependence after curative (chemo-) radiation in head and neck cancer

BACKGROUND

Curative radiotherapy or chemoradiation for head and neck cancer (HNC) may result in severe acute and late side effects, including tube feeding dependence. The purpose of this prospective cohort study was to develop a prediction model for tube feeding dependence 6 months (TUBEM6) after curative (chemo-) radiotherapy in HNC patients.

PATIENTS AND METHODS

Tube feeding dependence was scored prospectively. To develop the multivariable model, a group LASSO analysis was carried out, with TUBEM6 as the primary endpoint (n = 427). The model was then validated in a test cohort (n = 183). The training cohort was divided into three groups based on the risk of TUBEM6 to test whether the model could be extrapolated to later time points (12, 18 and 24 months).

RESULTS

Most important predictors for TUBEM6 were weight loss prior to treatment, advanced T-stage, positive N-stage, bilateral neck irradiation, accelerated radiotherapy and chemoradiation. Model performance was good, with an Area under the Curve of 0.86 in the training cohort and 0.82 in the test cohort. The TUBEM6-based risk groups were significantly associated with tube feeding dependence at later time points (p<0.001).

CONCLUSION

We established an externally validated predictive model for tube feeding dependence after curative radiotherapy or chemoradiation, which can be used to predict TUBEM6.

Comparison of 3D confromal radiotherapy and intensity modulated radiotherapy with or without simultaneous integrated boost during concurrent chemoradiation for locally advanced head and neck cancers

OBJECTIVE

Radiotherapy techniques have evolved from 3D conformal radiotherapy (3D-CRT) to intensity modulated radiotherapy (IMRT) where boost fields are delivered either sequentially (IMRTseq) or with a simultaneous integrated boost (IMRT+SIB). Our goal was to compare the outcomes of patients treated with IMRT+SIB to traditional standards.

METHODS

We analyzed the efficacy and toxicity of patients treated with concurrent chemoradiation using 3D-CRT, IMRTseq or IMRT+SIB. Between 1993 and 2012, 379 patients with non-metastatic Stage III-IV head and neck squamous cell cancer were treated with concurrent chemoradiation using 3D-CRT (n = 125), IMRTseq (n = 120) and IMRT+SIB (n = 134).

RESULTS

Patients treated with any technique had similar rates of 2y local control, 2y regional control, 2y progression free survival and 2y overall survival. Patients treated with IMRT+SIB had lower rates acute toxicity according to Grade 3 or greater mucositis (3D-CRT: 44.0% vs. IMRTseq: 36.7% vs. IMRT+SIB: 22.4%; P<.0001), dermatitis (3D-CRT: 44.0% vs. IMRTseq: 20.0% vs. IMRT+SIB: 7.5%; P<.0001) and feeding tube placement during radiotherapy (3D-CRT: 80.0% vs. IMRTseq: 50.8% vs. IMRT+SIB: 44.0%; P<.0001) as well as late toxicity as measured by feeding tube use (P<.0001) and tracheostomy use (P<.0001). On multivariate analysis, IMRT+SIB predicted for less mucositis, dermatitis and feeding tube use compared to 3D-CRT and for less dermatitis compared to IMRTseq.

CONCLUSIONS

Compared to 3D-CRT and IMRTseq, IMRT+SIB provided similar outcomes and potentially less toxicity indicating it is a feasible technique for chemoradiation in locally advanced head and neck cancer.

Combined modality treatment of laryngeal squamous cell carcinoma

Squamous cell carcinoma of the larynx is a major public health concern; it causes substantial morbidity and mortality, and arises chiefly as a result of tobacco and alcohol consumption. Early stage disease is best treated with radiation or surgery alone, but for patients with more locally advanced squamous cell carcinoma of the larynx, combined modality treatment has been shown to benefit selected patients, particularly when cisplatin-based chemotherapy and concurrent radiation therapy are employed, with or without altered fractionated radiation therapy. Substantial laryngectomy-associated quality-of-life decrements can be avoided in selected, potentially resectable patients with organ-sparing approaches, without sacrificing survival. Recently, trials have addressed the role of targeted systemic agents to the epidermal growth factor receptor, and other targets are under investigation. The addition of induction chemotherapy to concurrent chemoradiotherapy is a promising treatment strategy that warrants further evaluation, but has not yet emerged as a standard of care; the toxicity of such regimens must be balanced with the potential benefits on a case-by-case basis, and functional outcomes are often quite variable. Treatment planning, management and follow-up are complex, and thus should ideally be performed in a comprehensive, multidisciplinary fashion, in a center accustomed to a high volume of such cases. Future research directions are described herein.

Head and neck squamous cell carcinoma: optimizing the therapeutic index

The four recent noteworthy strategies aimed at improving therapeutic outcomes for the curative treatment of head and neck squamous cancers include the development of altered fractionation regimens, integration of chemotherapy, incorporation of intensity-modulated radiation therapy and introduction of targeted biologic therapy. Clinical investigations during the last 30 years have demonstrated the benefits of biologically sound altered fractionation and concurrent chemoradiation regimens in improving locoregional control and overall survival. These results have contributed to redefining the standard of care, with the caveat that proper patient selection for those who will benefit from potentially toxic combined modality treatment regimens remains controversial. These benefits have come at the expense of increased acute toxicity (i.e., mucositis) and sometimes at the expense of late toxicity (i.e., fibrosis and dysphagia). There are two additional developments that may help to further widen the therapeutic ratio. Intensity-modulated radiation therapy allows for the delivery of a highly conformal 3D radiation dose distribution around intended targets, thereby limiting the volumes of mucosa receiving a high dose per fraction and high total doses. The technical basis for intensity-modulated radiation therapy delivery reopens many fractionation questions that are still being addressed and challenges us to determine which of these is optimal for use with intensity-modulated radiation therapy alone or in combination with concurrent sensitizers. Finally, combined radiation therapy and biologic therapies directed at targets expressed predominately or exclusively by tumor cells have the promise to help increase tumor cell kill, while at least not substantially increasing normal tissue toxicity. These strategies are reviewed in a clinical context.

Re-irradiation of unresectable recurrent head and neck cancer: using Helical Tomotherapy as image-guided intensity-modulated radiotherapy

Purpose

Re-irradiation (re-RT) is considered a treatment option for inoperable locoregionally recurrent head and neck cancer (HNC) after prior radiotherapy. We evaluated the efficacy and safety of re-RT using Helical Tomotherapy as image-guided intensity-modulated radiotherapy in recurrent HNC.

Materials and Methods

Patients diagnosed with recurrent HNC and received re-RT were retrospectively reviewed. Primary endpoint was overall survival (OS) and secondary endpoints were locoregional control and toxicities.

Results

The median follow-up period of total 9 patients was 18.7 months (range, 4.1 to 76 months) and that of 3 alive patients was 49 months (range, 47 to 76 months). Median dose of first radiotherapy and re-RT was 64.8 and 47.5 Gy₁₀. Median cumulative dose of the two courses of radiotherapy was 116.3 Gy₁₀ (range, 91.8 to 128.9 Gy₁₀) while the median interval between the two courses of radiation was 25 months (range, 4 to 137 months). The response rate after re-RT of the evaluated 8 patients was 75% (complete response, 4; partial response, 2). Median locoregional relapse-free survival after re-RT was 11.9 months (range, 3.4 to 75.1 months) and 5 patients eventually presented with treatment failure (in-field failure, 2; in- and out-field failure, 2; out-field failure, 1). Median OS of the 8 patients was 20.3 months (range, 4.1 to 75.1 months). One- and two-year OS rates were 62.5% and 50%, respectively. Grade 3 leucopenia developed in one patient as acute toxicity, and grade 2 osteonecrosis and trismus as chronic toxicity in another patient.

Conclusion

Re-RT using Helical Tomotherapy for previously irradiated patients with unresectable locoregionally recurrent HNC may be a feasible treatment option with long-term survival and acceptable toxicities.

Improving therapeutic ratio in head and neck cancer with adjuvant and cisplatin-based treatments

Advanced head and neck cancers are difficult to manage despite the large treatment arsenal currently available. The multidisciplinary effort to increase disease-free survival and diminish normal tissue toxicity was rewarded with better locoregional control and sometimes fewer side effects. Nevertheless, locoregional recurrence is still one of the main reasons for treatment failure. Today, the standard of care in head and neck cancer management is represented by altered fractionation radiotherapy combined with platinum-based chemotherapy. Targeted therapies as well as chronotherapy were trialled with more or less success. The aim of the current work is to review the available techniques, which could contribute towards a higher therapeutic ratio in the treatment of advanced head and neck cancer patients.

Semiautomatic methods for segmentation of the proliferative tumour volume on sequential FLT PET/CT images in head and neck carcinomas and their relation to clinical outcome

PURPOSE

Radiotherapy of head and neck cancer induces changes in tumour cell proliferation during treatment, which can be depicted by the PET tracer (18)F-fluorothymidine (FLT). In this study, three advanced semiautomatic PET segmentation methods for delineation of the proliferative tumour volume (PV) before and during (chemo)radiotherapy were compared and related to clinical outcome.

METHODS

The study group comprised 46 patients with 48 squamous cell carcinomas of the head and neck, treated with accelerated (chemo)radiotherapy, who underwent FLT PET/CT prior to treatment and in the 2nd and 4th week of therapy. Primary gross tumour volumes were visually delineated on CT images (GTV CT). PVs were visually determined on all PET scans (PV VIS). The following semiautomatic segmentation methods were applied to sequential PET scans: background-subtracted relative-threshold level (PV RTL), a gradient-based method using the watershed transform algorithm and hierarchical clustering analysis (PV W&C), and a fuzzy locally adaptive Bayesian algorithm (PV FLAB).

RESULTS

Pretreatment PV VIS correlated best with PV FLAB and GTV CT. Correlations with PV RTL and PV W&C were weaker although statistically significant. During treatment, the PV VIS, PV W&C and PV FLAB significant decreased over time with the steepest decline over time for PV FLAB. Among these advanced segmentation methods, PV FLAB was the most robust in segmenting volumes in the third scan (67 % of tumours as compared to 40 % for PV W&C and 27 % for PV RTL). A decrease in PV FLAB above the median between the pretreatment scan and the scan obtained in the 4th week was associated with better disease-free survival (4 years 90 % versus 53 %).

CONCLUSION

In patients with head and neck cancer, FLAB proved to be the best performing method for segmentation of the PV on repeat FLT PET/CT scans during (chemo)radiotherapy. This may potentially facilitate radiation dose adaptation to changing PV.

Pure accelerated radiation versus concomitant chemoradiation in selected cases of locally advanced carcinoma cervix: a prospective study

OBJECTIVE

This non-randomized study was conducted to assess and compare the response and safety of true accelerated radiation alone to concomitant chemoradiation in locally advanced squamous cell carcinoma of the uterine cervix.

METHODS

Sixty patients with locally advanced squamous cell carcinoma of the uterine cervix, FIGO Stages (2009) IB2-IIIB were non-randomized to receive six fractions per week of external beam radiation (EBRT) (will be henceforth referred to as Arm A or Study arm or pure accelerated radiation arm) and five fractions per week of EBRT and chemotherapy with inj cisplatin 40 mg/m(2) i.v. every Monday during the course of EBRT (will be henceforth referred to as Arm B or Control arm or chemoradiation arm).

RESULTS

The median follow-up was 15 months in both the arms. The overall treatment time was 56.54 days for Arm A and 62.59 days for patients in Arm B (P value < 0.000**). The median EBRT time was 32.25 days in Arm A and 38.85 days in Arm B, a statistically significant delay for patients of chemoradiation Arm B (P value < 0.000**). The response assessment at the end of the study was not statistically different among the patients in both the treatment arms (P value 0.631).

CONCLUSION

The early responses to treatment with pure accelerated EBRT are non-inferior to concomitant chemoradiation and the acute toxicities are lesser.

Increased local failure risk with prolonged radiation treatment time in head and neck cancer treated with concurrent chemotherapy

BACKGROUND

Prolonged radiation treatment time (RTT) in head and neck squamous cell carcinoma (HNSCC) is associated with inferior tumor control in patients treated with radiation therapy (RT) alone. However, the significance of prolonged RTT with concurrent chemotherapy is less clear.

METHODS

We reviewed outcomes for 171 patients with primary HNSCC treated with curative intent RT and concurrent drug therapy from 2001 to 2009. The effects of RTT and other variables on local control and survival were analyzed.

RESULTS

Patients with RTT >7 weeks had a significantly increased risk of local failure (hazard ratio [HR], 2.6; p = .018) and death (HR, 1.9 p = .035). These results retained significance even after adjustment for tumor stage (age was not significant).

CONCLUSION

For patients treated with concurrent chemoradiotherapy (chemoRT), prolonged RTT may compromise tumor control as has been established in the setting of RT alone. Symptoms of patients with HNSCC undergoing definitive chemoRT should be managed aggressively to limit treatment interruptions.

Human papillomavirus and oropharyngeal cancer in Greenland in 1994-2010

Background

Oropharyngeal squamous cell carcinoma (OPSCC) is associated with the sexually transmitted human papillomavirus (HPV), smoking and alcohol. In Greenland, a high rate of HPV-induced cervical cancer and venereal diseases are found, which exposes the population for high risk of HPV infection. In Greenland, only girls are included in the mandatory HPV vaccination program.

Objective

To investigate the annual incidence of OPSCC and the proportion of HPV-associated OPSCC (HPV+ OPSCC) in Greenland in 1994–2010.

Design

At Rigshospitalet, University of Copenhagen, we identified all Greenlandic patients diagnosed and treated for OPSCC from 1994 to 2010. Sections were cut from the patient's paraffin-embedded tissue blocks and investigated for p16 expression by immunohistochemistry. HPV analyses were performed with 2 sets of general HPV primers and 1 set of HPV16-specific primer. HPV+ OPSCC was defined as both >75% p16+ cells and PCR positive for HPV.

Results

Of 26 Greenlandic patients diagnosed with OPSCC, 17 were males and 9 were females. The proportion of HPV+ OPSCC in the total study period was 22%, without significant changes in the population in Greenland. We found an increase in the proportion of HPV+ OPSCC from 14% in 1994–2001 to 25% in 2002–2010 (p=0.51). Among males from 20 to 27% (p=0.63) and in females from 0 to 20% (p=0.71). The annual OPSCC incidence increased from 2.3/100,000 (CI=1.2–4.2) in 1994–2001 to 3.8/100,000 (CI=2.4–6.2) in 2002–2010: among males from 2.4/100,000 (CI=1.0–5.7) to 5.0/100,000 (CI=2.9–8.9).

Conclusion

Even though the population is at high risk of HPV infection, the proportion of 22% HPV+ OPSCC in the total study period is low compared to Europe and the United States. This might be explained by our small study size and/or by ethnic, geographical, sexual and cultural differences. Continuing observations of the OPSCC incidence and the proportion of HPV+ OPSCC in Greenland are needed.

Outcomes after primary chemoradiotherapy for N3 (>6 cm) head and neck squamous cell carcinoma after an FDG-PET--guided neck management policy

BACKGROUND

The purpose of this study was to assess whether a positron emission tomography (PET)-directed policy remains appropriate for managing neck nodes (N3; >6 cm) in head and neck squamous cell carcinoma (HNSCC).

METHODS

All patients with N3 (>6 cm) HNSCC treated with definitive chemoradiotherapy (CRT) at our institution between 2005 and 2012 were included in the analysis. Patients underwent PET assessment before and 12 weeks after CRT. Neck dissections were performed for PET-avid residual nodal abnormalities after complete response at the primary site. Rate of isolated nodal failure (INF) was the primary outcome.

RESULTS

Median follow-up from diagnosis for 33 patients was 30 months (range, 6-76 months). INF occurred in 2 patients (6%) with neck dissections performed in 4 cases (12%). First failure was predominantly distant metastatic (10; 30%).

CONCLUSION

The rate of INF remains low when following a PET-directed neck management policy after definitive CRT for N3 (>6 cm) HNSCC.

Factors associated with acute and late dysphagia in the DAHANCA 6 & 7 randomized trial with accelerated radiotherapy for head and neck cancer

BACKGROUND

Dysphagia is a common and debilitating side effect in head and neck radiotherapy (RT). Prognostic factors are numerous and their interrelationship not well understood. The aim of this study was to establish a multivariate prognostic model for acute and late dysphagia after RT, based on information from a prospective trial.

MATERIAL AND METHODS

The DAHANCA 6&7 randomized study included 1476 patients with head and neck cancer eligible for primary RT alone. Patients were randomized between 5 and 6 weekly fractions of conventional RT, and received 62-70 Gy in 31-35 fractions. Patients were scored for dysphagia weekly during treatment and at regular intervals until five years after treatment. Dysphagia scores were available from 1461 patients.

RESULTS

Acute dysphagia according to DAHANCA grades 1, 2, 3 and 4 occurred in 83%, 71%, 43% and 23%, respectively. Severe dysphagia occurred in 47% and 38% of patients receiving accelerated or conventional radiotherapy, respectively (p = 0.001). At one, two, three, four and five years the prevalence of chronic dysphagia above grade 0, was 46%, 32%, 29%, 24%, 23%, respectively with no difference between 5 and 6 fractions. In multivariate analysis, the following parameters were independent factors for severe acute dysphagia: T3-T4 tumors, N-positive disease, non-glottic cancer, age> median, baseline dysphagia > 1 and accelerated radiotherapy. The following factors were prognostic factors for late dysphagia: non-glottic cancer, T3-T4, N-positive disease and baseline dysphagia > 1. The data confirmed previously published predictive models, as it was possible to separate patients in groups with low, medium and high risk of dysphagia, respectively, based on pre-treatment risk scores.

CONCLUSION

Prognostic models were established to characterize patients at risk of developing acute or late dysphagia in the DAHANCA 6&7 trial. The results may be useful to identify patients at risk of dysphagia and thus candidates for prophylactic measures against swallowing dysfunction.

Molecular PET imaging for biology-guided adaptive radiotherapy of head and neck cancer

Integration of molecular imaging PET techniques into therapy selection strategies and radiation treatment planning for head and neck squamous cell carcinoma (HNSCC) can serve several purposes. First, pre-treatment assessments can steer decisions about radiotherapy modifications or combinations with other modalities. Second, biology-based objective functions can be introduced to the radiation treatment planning process by co-registration of molecular imaging with planning computed tomography (CT) scans. Thus, customized heterogeneous dose distributions can be generated with escalated doses to tumor areas where radiotherapy resistance mechanisms are most prevalent. Third, monitoring of temporal and spatial variations in these radiotherapy resistance mechanisms early during the course of treatment can discriminate responders from non-responders. With such information available shortly after the start of treatment, modifications can be implemented or the radiation treatment plan can be adapted tailing the biological response pattern. Currently, these strategies are in various phases of clinical testing, mostly in single-center studies. Further validation in multicenter set-up is needed. Ultimately, this should result in availability for routine clinical practice requiring stable production and accessibility of tracers, reproducibility and standardization of imaging and analysis methods, as well as general availability of knowledge and expertise. Small studies employing adaptive radiotherapy based on functional dynamics and early response mechanisms demonstrate promising results. In this context, we focus this review on the widely used PET tracer (18)F-FDG and PET tracers depicting hypoxia and proliferation; two well-known radiation resistance mechanisms.

Expression of EGFR and HPV-associated p16 in oropharyngeal carcinoma: correlation and influence on prognosis after radiotherapy in the randomized DAHANCA 5 and 7 trials

AIM

EGFR and HPV-associated p16 are among the most investigated biomarkers in head and neck cancer. The aim was to investigate the correlation and interaction between these two markers and to evaluate their potential prognostic significance when combined.

MATERIALS AND METHODS

336 Oropharyngeal carcinomas treated with primary radiotherapy (66-68 Gy, 2fx/day, 10-12 Gy/week) and with known EGFR/p16-status estimated semiquantitatively by immunohistochemistry were included in the study. Data were evaluated by EGFR-expression (high/low) and p16-status (positive/negative) consequently dividing tumours into four groups by combination of the biomarkers. Patient/tumour characteristics and complete 5-year follow-up were available.

RESULTS

Low EGFR-expression was significantly more common in p16-positive tumours compared to p16-negative, p < 0.0001. p16 positivity showed a strong prognostic impact (p < 0.0001, HR = 0.22 [0.13-0.38]), whereas EGFR was a weak prognostic marker when local control was used as endpoint (p = 0.03, HR = 0.53 [0.29-0.94]). Combination of EGFR/p16 did not add significant information to p16 alone and by multivariable analysis only p16 showed significant prognostic information for all evaluated endpoints.

CONCLUSIONS

Both EGFR and p16 bear prognostic information in oropharyngeal cancer, although p16 is, by far, the strongest prognostic factor. The markers seem to be correlated and this might have influence when evaluating the effect of EGFR inhibition in oropharyngeal tumours.

Analysis of fractionation correction methodologies for multiple phase treatment plans in radiation therapy

PURPOSE

Radiation therapy is often delivered by multiple sequential treatment plans. For an accurate radiobiological evaluation of the overall treatment, fractionation corrections to each dose distribution must be applied before summing the three-dimensional dose matrix of each plan since the simpler approach of performing the fractionation correction to the total dose-volume histograms, obtained by the arithmetical sum of the different plans, becomes inaccurate for more heterogeneous dose patterns. In this study, the differences between these two fractionation correction methods, named here as exact (corrected before) and approximate (after summation), respectively, are assessed for different cancer types.

METHODS

Prostate, breast, and head and neck (HN) tumor patients were selected to quantify the differences between two fractionation correction methods (the exact vs the approximate). For each cancer type, two different treatment plans were developed using uniform (CRT) and intensity modulated beams (IMRT), respectively. The responses of the target and normal tissue were calculated using the Poisson linear-quadratic-time model and the relative seriality model, respectively. All treatments were radiobiologically evaluated and compared using the complication-free tumor control probability (P+), the biologically effective uniform dose (D) together with common dosimetric criteria.

RESULTS

For the prostate cancer patient, an underestimation of around 14%-15% in P+ was obtained when the fractionation correction was applied after summation compared to the exact approach due to significant biological and dosimetric variations obtained between the two fractionation correction methods in the involved lymph nodes. For the breast cancer patient, an underestimation of around 3%-4% in the maximum dose in the heart was obtained. Despite the dosimetric differences in this organ, no significant variations were obtained in treatment outcome. For the HN tumor patient, an underestimation of about 5% in treatment outcome was obtained for the CRT plan as a result of an underestimation of the planning target volume control probability by about 10%. An underestimation of about 6% in the complication probability of the right parotid was also obtained. For all the other organs at risk, dosimetric differences of up to 4% were obtained but with no significant impact in the expected clinical outcome. However, for the IMRT plan, an overestimation in P+ of 4.3% was obtained mainly due to an underestimation of the complication probability of the left and right parotids (2.9% and 5.8%, respectively).

CONCLUSIONS

The use of the exact fractionation correction method, which is applying fractionation correction on the separate dose distributions of a multiple phase treatment before their summation was found to have a significant expected clinical impact. For regions of interest that are irradiated with very heterogeneous dose distributions and significantly different doses per fraction in the different treatment phases, the exact fractionation correction method needs to be applied since a significant underestimation of the true patient outcome can be introduced otherwise.

Clinical perspectives of cancer stem cell research in radiation oncology

Radiotherapy has a proven potential to eradicate cancer stem cells which is reflected by its curative potential in many cancer types. Considerable progress has been made in identification and biological characterisation of cancer stem cells during the past years. Recent biological findings indicate significant inter- and intratumoural and functional heterogeneity of cancer stem cells and lead to more complex models which have potential implications for radiobiology and radiotherapy. Clinical evidence is emerging that biomarkers of cancer stem cells may be prognostic for the outcome of radiotherapy in some tumour entities. Perspectives of cancer stem cell based research for radiotherapy reviewed here include their radioresistance compared to the mass of non-cancer stem cells which form the bulk of all tumour cells, implications for image- and non-image based predictive bio-assays of the outcome of radiotherapy and a combination of novel systemic treatments with radiotherapy.

The start of chemotherapy until the end of radiotherapy in patients with limited-stage small cell lung cancer

BACKGROUND/AIMS

Chemotherapy combined with radiation therapy is the standard treatment for limited stage small cell lung cancer (LS-SCLC). Although numerous studies indicate that the overall duration of chemoradiotherapy is the most relevant predictor of outcome, the optimal chemotherapy and radiation schedule for LS-SCLC remains controversial. Therefore we analyzed the time from the start of any treatment until the end of radiotherapy (SER) in patients with LS-SCLC.

METHODS

We retrospectively analyzed 29 patients diagnosed histologically with LS-SCLC and divided them into two groups: a short SER group (< 60 days) and a long SER (> 60 days) group. Patients were treated with irinotecan-based chemotherapy and thoracic radiotherapy.

RESULTS

Sixteen patients were in the short SER group and 13 patients were in the long SER group. Short SER significantly prolonged survival rate (p = 0.03) compared with that of long SER. However, no significant differences in side effects were observed.

CONCLUSIONS

Short SER should be considered to improve the outcome of concurrent chemoradiotherapy for LS-SCLC.

Radiotherapy with fraction size of 2.25 Gy in T1-2 laryngeal and hypopharyngeal cancer

This study was carried out to evaluate the influence of fraction size 2.25 Gy on local control of T1 and T2 laryngeal and hypopharyngeal cancers. Between August 2002 and December 2010, 80 patients with T1 and T2 laryngeal or hypopharyngeal cancers were treated with definitive radiotherapy with a fraction size of 2.25 Gy. Primary sites were the larynx in 69 and the hypopharynx in 11. Fifty-three patients were T1 and 27 were T2. All patients' pathology was squamous cell carcinoma except one carcinosarcoma. Radiotherapy was delivered 5 days/week with a 4-MV photon beam up to a total dose of 63.0 Gy. Median treatment time was 41 days. Statistical analysis of survival was calculated using the Kaplan-Meier method. No acute toxicity greater than grade 2 (CTCAE ver. 3.0.) including mucositis and dermatitis was observed. All but one patient had a complete response. The partial response patient received salvage surgery. The median follow-up period was 47 months (ranging from 4 to 108 months). No late toxicity greater than 1 was observed. Nine patients developed recurrence, seven local and two neck lymph nodes. Three patients died, one from laryngeal cancer and two from intercurrent diseases. The 5-year local control rates (LCRs) in the entire group, larynx T1, larynx T2 and hypopharynx T1 were 85.8%, 97.6%, 70.1% and 85.7%, respectively. The LCRs of T1 improved compared with our historical control, but not those of T2. The 2.25-Gy fraction size is safe and may have the potential to achieve good LCR in T1 lesions.

Advances in radiation oncology for the management of oropharyngeal tumors

The major benefits of modern radiation therapy (eg, intensity-modulated [x-ray] radiation therapy [IMRT]) for oropharyngeal cancer are reduced xerostomia and better quality of life. Intensity-modulated proton therapy may provide additional advantages over IMRT by reducing radiation beam-path toxicities. Several acute and late treatment-related toxicities and symptom constellations must be kept in mind when designing and comparing future treatment strategies, particularly because currently most patients with oropharyngeal carcinoma present with human papillomavirus-positive disease and are expected to have a high probability of long-term survival after treatment.