IMRT in oral cavity cancer

Evaluation of survival outcome and prognostic factors for oral cavity cancer treated with volumetric arc therapy

PURPOSE

This study aimed to evaluate the survival outcomes and identify prognostic factors for patients with oral cavity cancer (OCC) who underwent adjuvant treatment with volumetric arc therapy (VMAT) using simultaneous integrated boost (SIB).

METHODS

Data was collected for post-operated patients of carcinoma of oral cavity who received adjuvant VMAT with SIB between June 2018 and December 2022. The data was entered and analyzed using SPSS software version 20.0. Survival rates were estimated using Kaplan Meier method. To determine survival difference between the groups, log rank test was used. Multivariate analyses were performed with Cox proportional hazard model and p value < 0.05 was considered as significant.

RESULTS

A total of 178 patients were included in the study. The median follow-up period was 26 months (range 3-56 months). The 3-year OS, DFS, and LRC rates were 78% (95% CI 77-79%), 76% (95% CI 74-77%), and 81% (95% CI 80-82%), respectively. Univariate analysis identified age ≥ 50 years, lymph node involvement, extracapsular extension (ECE), and N2-N3 disease as significant adverse prognostic factors for OS, DFS, and LRC. Multivariate analysis confirmed age ≥ 50 years and nodal involvement as independent predictors of worse OS, DFS, and LRC. Additionally, ECE independently affected OS and DFS.

CONCLUSION

Adjuvant treatment with VMAT using SIBin patients with OCC is effective. Age and nodal involvement had significant impact on LRC, DFSand OS while ECE on DFSand OS.

Risk factors associated with the mortality rate of oral squamous cell carcinoma patients: A 10-year retrospective study

In Malaysia, oral cancer is very common and the reported 5-year survival of such patients is nearly 50% after treatment with surgery and radiotherapy, much lower than most of the developed countries. This study aimed to investigate the socio-demographic and clinicopathological parameters that influence the mortality rate of the patients suffering from oral squamous cell carcinoma (OSCC) in the Kelantanse population.In this retrospective study, data regarding socio-demographic, clinicopathological factors, and treatment outcome associated with OSCC were gathered from the archives of the medical records office of Hospital Universiti Sains Malaysia. For statistical analysis, simple and multiple logistic regression were performed. The significance level was set to P < .25.A total of 211 OSCC cases were registered in Hospital Universiti Sains Malaysia from January 1, 2000 to December 31, 2018. Majority of them were male (57.82%), non-smoker (54.97%), non-alcohol consumer (91.94%), and non-betel quid chewer (93.83%) Malay (60.66%) patients. The tongue was the most commonly involved part of the oral cavity (41.52%). Histologically, the majority of the cases had moderately-differentiated OSCC (52.82%). Most of the patients were diagnosed at stage IV at the time of diagnosis (61.61%). When this study was performed, the survival status of the majority of the patients was alive (68.24%).Within the analyzed socio-demographic and clinicopathological parameters, gender, alcohol consumption, T-classification, histological grading, and treatment status have been demonstrated as an independent risk factors for mortality rate in multivariate analysis. Hence, these parameters need to be taken into account for the individualized therapy management of OSCC patients.

Opportunities and Limits in Salvage Surgery in Persistent or Recurrent Head and Neck Squamous Cell Carcinoma

Except for HPV-induced cancers of the oropharynx, survival rates in patients with squamous cell carcinoma of the head and neck (HNSCC) have not changed substantially over the last decades. Salvage surgery plays an important role where primary treatment was unsuccessful since 50% of advanced-stage patients relapse after nonsurgical primary treatment. Depending on a variety of factors, a considerable number of patients in whom primary treatment was not successful can still be cured by salvage surgery. It is the goal of this review to elucidate these factors with the aim to counsel patients and their relatives realistically about the chances of being cured.

Non-operative management for oral cavity carcinoma: Definitive radiation therapy as a potential alternative treatment approach

PURPOSE

To determine the outcomes of oral cavity squamous cell cancer (OSCC) patients treated with non-surgical approach i.e. definitive intensity-modulated radiation therapy (IMRT).

METHODS

All OSCC patients treated radically with IMRT (without primary surgery) between 2005-2014 were reviewed in a prospectively collected database. OSCC patients treated with definitive RT received concurrent chemotherapy except for early stage patients or those who declined or were unfit for chemotherapy. The 5-year local, and regional, distant control rates, disease-free, overall, and cancer-specific survival, and late toxicity were analyzed.

RESULTS

Among 1316 OSCC patients treated with curative-intent; 108 patients (8%) received non-operative management due to: medical inoperability (n = 14, 13%), surgical unresectability (n = 8, 7%), patient declined surgery (n = 15, 14%), attempted preservation of oral structure/function in view of required extensive surgery (n = 53, 49%) or extensive oropharyngeal involvement (n = 18, 17%). Sixty-eight (63%) were cT3-4, 38 (35%) were cN2-3, and 38 (35%) received concurrent chemotherapy. With a median follow-up of 52 months, the 5-year local, regional, distant control rate, disease-free, overall, and cancer-specific survival were 78%, 92%, 90%, 42%, 50%, and 76% respectively. Patients with cN2-3 had higher rate of 5-year distant metastasis (24% vs 3%, p = 0.001), with detrimental impact on DFS (p = 0.03) and OS (p < 0.02) on multivariable analysis. Grade ≥ 3 late toxicity was reported in 9% of patients (most common: grade 3 osteoradionecrosis in 6%).

CONCLUSIONS

Non-operative management of OSCC resulted in a meaningful rate of locoregional control, and could be an alternative curative approach when primary surgery would be declined, unsuitable or unacceptably delayed.

Interventions for preventing osteoradionecrosis of the jaws in adults receiving head and neck radiotherapy

BACKGROUND

Osteoradionecrosis (ORN) of the jaws is among the most serious oral complications of head and neck cancer radiotherapy, arising from radiation-induced fibro-atrophic tissue injury, manifested by necrosis of osseous tissues and failure to heal, often secondary to operative interventions in the oral cavity. It is associated with considerable morbidity and has important quality of life ramifications. Since ORN is very difficult to treat effectively, preventive measures to limit the onset of this disease are needed; however, the effects of various preventive interventions has not been adequately quantified.

OBJECTIVES

To assess the effects of interventions for preventing ORN of the jaws in adult patients with head and neck cancer undergoing curative or adjuvant (i.e. non-palliative) radiotherapy.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 5 November 2019), the Cochrane Central Register of Controlled Trials (CENTRAL; 2019, Issue 10) in the Cochrane Library (searched 5 November 2019), MEDLINE Ovid (1946 to 5 November 2019), Embase Ovid (1980 to 5 November 2019), Allied and Complementary Medicine (AMED) Ovid (1985 to 5 November 2019), Scopus (1966 to 5 November 2019), Proquest Dissertations and Theses International (1861 to 5 November 2019) and Web of Science Conference Proceedings (1990 to 5 November 2019). The US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

We selected randomised controlled trials (RCTs) or quasi-RCTs of adult patients 18 years or older with head and neck cancer who had undergone curative or adjuvant radiotherapy to the head and neck, who had received an intervention to prevent the onset of ORN. Eligible patients were those subjected to pre- or post-irradiation dental evaluation. Management of these patients was to be with interventions independent of their cancer therapy, including but not limited to local, systemic, or behavioural interventions.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials from search results, assessed risk of bias, and extracted relevant data for inclusion in the review. Authors of included studies were contacted to request missing data. We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

Four studies were identified that met pre-determined eligibility criteria, evaluating a total of 342 adults. From the four studies, all assessed as at high risk of bias, three broad interventions were identified that may potentially reduce the risk of ORN development: one study showed no reduction in ORN when using platelet-rich plasma placed in the extraction sockets of prophylactically removed healthy mandibular molar teeth prior to radiotherapy (odds ratio (OR) 3.32, 95% confidence interval (CI) 0.58 to 19.09; one trial, 44 participants; very low-certainty evidence). Another study involved comparing fluoride gel and high-content fluoride toothpaste (1350 parts per million (ppm)) in prevention of post-radiation caries, and found no difference between their use as no cases of ORN were reported (one trial, 220 participants; very low-certainty evidence). The other two studies involved the use of perioperative hyperbaric oxygen (HBO) therapy and antibiotics. One study showed that treatment with HBO caused a reduction in the development of ORN in comparison to patients treated with antibiotics following dental extractions (risk ratio (RR) 0.18, 95% CI 0.43 to 0.76; one trial, 74 participants; very low-certainty evidence). Another study found no difference between combined HBO and antibiotics compared to antibiotics alone prior to dental implant placement (RR 3.00, 95% CI 0.14 to 65.16; one trial, 26 participants; very low-certainty evidence). Adverse effects of the different interventions were not reported clearly or were not important.

AUTHORS' CONCLUSIONS

Given the suboptimal reporting and inadequate sample sizes of the included studies, evidence regarding the interventions evaluated by the trials included in this review is uncertain. More well-designed RCTs with larger samples are required to make conclusive statements regarding the efficacy of these interventions.

Interventions for the treatment of oral and oropharyngeal cancers: surgical treatment

BACKGROUND

Surgery is an important part of the management of oral cavity cancer with regard to both the removal of the primary tumour and removal of lymph nodes in the neck. Surgery is less frequently used in oropharyngeal cancer. Surgery alone may be treatment for early-stage disease or surgery may be used in combination with radiotherapy, chemotherapy and immunotherapy/biotherapy. There is variation in the recommended timing and extent of surgery in the overall treatment regimens of people with these cancers. This is an update of a review originally published in 2007 and first updated in 2011.

OBJECTIVES

To determine which surgical treatment modalities for oral and oropharyngeal cancers result in increased overall survival, disease-free survival and locoregional control and reduced recurrence. To determine the implication of treatment modalities in terms of morbidity, quality of life, costs, hospital days of treatment, complications and harms.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 20 December 2017), the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 11), MEDLINE Ovid (1946 to 20 December 2017) and Embase Ovid (1980 to 20 December 2017). We searched the US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform for ongoing trials. There were no restrictions on the language or date of publication.

SELECTION CRITERIA

Randomised controlled trials where more than 50% of participants had primary tumours of the oral cavity or oropharynx, or where separate data could be extracted for these participants, and that compared two or more surgical treatment modalities, or surgery versus other treatment modalities.

DATA COLLECTION AND ANALYSIS

Two or more review authors independently extracted data and assessed risk of bias. We contacted study authors for additional information as required. We collected adverse events data from included studies.

MAIN RESULTS

We identified five new trials in this update, bringing the total number of included trials to 12 (2300 participants; 2148 with cancers of the oral cavity). We assessed four trials at high risk of bias, and eight at unclear. None of the included trials compared different surgical approaches for the excision of the primary tumour. We grouped the trials into seven main comparisons.Future research may change the findings as there is only very low-certainty evidence available for all results.Five trials compared elective neck dissection (ND) with therapeutic (delayed) ND in participants with oral cavity cancer and clinically negative neck nodes, but differences in type of surgery and duration of follow-up made meta-analysis inappropriate in most cases. Four of these trials reported overall and disease-free survival. The meta-analyses of two trials found no evidence of either intervention leading to greater overall survival (hazard ratio (HR) 0.84, 95% confidence interval (CI) 0.41 to 1.72; 571 participants), or disease-free survival (HR 0.73, 95% CI 0.25 to 2.11; 571 participants), but one trial found a benefit for elective supraomohyoid ND compared to therapeutic ND in overall survival (RR 0.40, 95% CI 0.19 to 0.84; 67 participants) and disease-free survival (HR 0.32, 95% CI 0.12 to 0.84; 67 participants). Four individual trials assessed locoregional recurrence, but could not be meta-analysed; one trial favoured elective ND over therapeutic delayed ND, while the others were inconclusive.Two trials compared elective radical ND with elective selective ND, but we were unable to pool the data for two outcomes. Neither study found evidence of a difference in overall survival or disease-free survival. A single trial found no evidence of a difference in recurrence.One trial compared surgery plus radiotherapy with radiotherapy alone, but data were unreliable because the trial stopped early and there were multiple protocol violations.One trial comparing positron-emission tomography-computed tomography (PET-CT) following chemoradiotherapy (with ND only if no or incomplete response) versus planned ND (either before or after chemoradiotherapy), showed no evidence of a difference in mortality (HR 0.92, 95% CI 0.65 to 1.31; 564 participants). The trial did not provide usable data for the other outcomes.Three single trials compared: surgery plus adjunctive radiotherapy versus chemoradiotherapy; supraomohyoid ND versus modified radical ND; and super selective ND versus selective ND. There were no useable data from these trials.The reporting of adverse events was poor. Four trials measured adverse events. Only one of the trials reported quality of life as an outcome.

AUTHORS' CONCLUSIONS

Twelve randomised controlled trials evaluated ND surgery in people with oral cavity cancers; however, the evidence available for all comparisons and outcomes is very low certainty, therefore we cannot rely on the findings. The evidence is insufficient to draw conclusions about elective ND of clinically negative neck nodes at the time of removal of the primary tumour compared to therapeutic (delayed) ND. Two trials combined in meta-analysis suggested there is no difference between these interventions, while one trial (which evaluated elective supraomohyoid ND) found that it may be associated with increased overall and disease-free survival. One trial found elective ND reduced locoregional recurrence, while three were inconclusive. There is no evidence that radical ND increases overall or disease-free survival compared to more conservative ND surgery, or that there is a difference in mortality between PET-CT surveillance following chemoradiotherapy versus planned ND (before or after chemoradiotherapy). Reporting of adverse events in all trials was poor and it was not possible to compare the quality of life of people undergoing different surgical treatments.

Patterns of failure after postoperative intensity-modulated radiotherapy for locally advanced buccal cancer: Initial masticator space involvement is the key factor of recurrence

BACKGROUND

The purpose of this study was to determine failure patterns and clinicopathologic prognostic factors in patients with locally advanced buccal cancer after postoperative intensity-modulated radiotherapy (IMRT).

METHODS

Eighty-two patients with locally advanced (American Joint Committee on Cancer [AJCC] stage III/IV) buccal cancer who underwent surgery followed by postoperative IMRT between January 2007 and October 2012 were retrospectively analyzed.

RESULTS

Eighteen patients had local recurrences as the first recurrent site and 11 had supramandibular notch recurrences; the majority of recurrences were classified as marginal failures. The median time from the first local or regional recurrence to death was 5.9 months. In multivariate analyses of survivals, the initial masticator space involvement was the most important prognostic factor. Masticator space involvement, N classification, and maxillectomy were the significant prognostic predictors for supramandibular notch recurrences.

CONCLUSION

Postoperative IMRT for buccal cancer should not include the surgical beds alone, rather, it should be based on the potential patterns of spread.

AHNS Series: Do you know your guidelines? Evidence-based management of oral cavity cancers

Oral cavity squamous cell carcinoma (OCSCC) is the most common nonmelanoma head and neck cancer in the world, with an estimated 405 000 new cases expected each year. Subsites of the oral cavity include the alveolar ridge, buccal mucosa, anterior tongue, tonsillar pillar, retromolar trigone, hard palate, gingiva, and floor of the mouth. In this issue of the AHNS "Do you know your guidelines?" series, we review the evidence-based approach to the management of oral cavity carcinomas based on the framework provided by the National Comprehensive Cancer Network (NCCN) Clinical Practice Guidelines in Oncology.

Patterns of locoregional failure following post-operative intensity-modulated radiotherapy to oral cavity cancer: quantitative spatial and dosimetric analysis using a deformable image registration workflow

Background

We sought to identify spatial/dosimetric patterns of failure for oral cavity cancer patients receiving post-operative IMRT (PO-IMRT).

Methods

Two hundred eighty-nine OCC patients receiving PO-IMRT were retrospectively reviewed from 2000 to 2012. Diagnostic CT documenting recurrence (rCT) was co-registered with planning CT (pCT) using a validated deformable image registration software. Manually segmented recurrent gross disease (rGTV) was deformed to co-registered pCTs. Mapped rGTVs were compared dosimetrically to planned dose and spatially to planning target volumes using centroid-based approaches. Failures types were classified using combined spatial/dosimetric criteria: A (central high-dose), B (peripheral high-dose), C (central intermediate/low-dose), D (peripheral intermediate/low-dose), and E (extraneous-dose).

Results

Fifty-four patients with recurrence were analyzed; 26 local recurrence, 19 regional recurrence, and 9 both local and regional recurrence. Median time to recurrence was 4 months (range 0–71). Median rGTVs volume was 3.7 cm³ (IQR 1.4–10.6). For spatial and dosimetric analysis of the patterns of failure, 30 patients (55.5%) were classified as type A (central high-dose). Non-central high dose failures were distributed as follows: 2 (3.7%) type B, 10 (18.5%) type C, 1 (1.8%) type D, and 9 (16.7%) type E. Non-IMRT failure in the matching low-neck field was seen in two patients. No failures were noted at the IMRT-supraclavicular field match-line.

Conclusions

Approximately half of patients with local/regional failure had non-central high dose recurrence. Peripheral high dose misses were uncommon reflecting adequate delineation and dose delivery. Future strategies are needed to reduce types C and E failures.

Electronic supplementary material

The online version of this article (doi:10.1186/s13014-017-0868-y) contains supplementary material, which is available to authorized users.

IMRT delivers lower radiation doses to dental structures than 3DRT in head and neck cancer patients

BACKGROUND

Radiotherapy (RT) is frequently used in the treatment of head and neck cancer, but different side-effects are frequently reported, including a higher frequency of radiation-related caries, what may be consequence of direct radiation to dental tissue. The intensity-modulated radiotherapy (IMRT) was developed to improve tumor control and decrease patient's morbidity by delivering radiation beams only to tumor shapes and sparing normal tissue. However, teeth are usually not included in IMRT plannings and the real efficacy of IMRT in the dental context has not been addressed. Therefore, the aim of this study is to assess whether IMRT delivers lower radiation doses to dental structures than conformal 3D radiotherapy (3DRT).

MATERIAL AND METHODS

Radiation dose delivery to dental structures of 80 patients treated for head and neck cancers (oral cavity, tongue, nasopharynx and oropharynx) with IMRT (40 patients) and 3DRT (40 patients) were assessed by individually contouring tooth crowns on patients' treatment plans. Clinicopathological data were retrieved from patients' medical files.

RESULTS

The average dose of radiation to teeth delivered by IMRT was significantly lower than with 3DRT (p = 0.007); however, only patients affected by nasopharynx and oral cavity cancers demonstrated significantly lower doses with IMRT (p = 0.012 and p = 0.011, respectively). Molars received more radiation with both 3DRT and IMRT, but the latter delivered significantly lower radiation in this group of teeth (p < 0.001), whereas no significant difference was found for the other dental groups. Maxillary teeth received lower doses than mandibular teeth, but only IMRT delivered significantly lower doses (p = 0.011 and p = 0.003). Ipsilateral teeth received higher doses than contralateral teeth with both techniques and IMRT delivered significantly lower radiation than 3DRT for contralateral dental structures (p < 0.001).

CONCLUSION

IMRT delivered lower radiation doses to teeth than 3DRT, but only for some groups of patients and teeth, suggesting that this decrease was more likely due to the protection of other high risk organs, and was not enough to remove teeth from the zone of high risk for radiogenic disturbance (>30Gy).

A feedback constraint optimization method for intensity-modulated radiation therapy of nasopharyngeal carcinoma

Intensity-modulated radiation therapy (IMRT) is able to achieve good target conformance with a limited dose to organs at risk (OARs); however, IMRT increases the irradiation volume and monitor units (MUs) required. The present study aimed to evaluate the use of an IMRT plan with fewer segments and MUs, while maintaining quality in the treatment of nasopharyngeal carcinoma. In the present study, two types of IMRT plan were therefore compared: The direct machine parameter optimization (DMPO)-RT method and the feedback constraint DMPO-RT (fc_DMPO-RT) method, which utilizes compensative feedback constraint in DMPO-RT and maintains optimization. Plans for 23 patients were developed with identical dose prescriptions. Each plan involved synchronous delivery to various targets, with identical OAR constraints, by means of 7 coplanar fields. The average dose, maximum dose, dose-volume histograms of targets and the OAR, MUs of the plan, the number of segments, delivery time and accuracy were subsequently compared. The fc_DMPO-RT exhibited superior dose distribution in terms of the average, maximum and minimum doses to the gross tumor volume compared with that of DMPO-RT (t=62.7, 20.5 and 22.0, respectively; P<0.05). The fc_DMPO-RT also resulted in a smaller maximum dose to the spinal cord (t=7.3; P<0.05), as well as fewer MUs, fewer segments and decreased treatment times than that of the DMPO-RT (t=6.2, 393.4 and 244.3, respectively; P<0.05). The fc_DMPO-RT maintained plan quality with fewer segments and MUs, and the treatment time was significantly reduced, thereby resulting in reduced radiation leakage and an enhanced curative effect. Therefore, introducing feedback constraint into DMPO may result in improved IMRT planning. In nasopharyngeal carcinoma specifically, feedback constraint resulted in the improved protection of OARs in proximity of targets (such as the brainstem and parotid) due to sharp dose distribution and reduced MUs.

Evaluation of oral prophylaxis during and after intensity-modulated radiotherapy due to head and neck cancer--a retrospective study

OBJECTIVES

The aim of this study was to retrospectively analyze the influence of a prophylaxis protocol of head and neck tumor (HNT) patients during and after intensity-modulated radiotherapy (IMRT).

MATERIAL AND METHOD

In this 5-year retrospective study (2009-2013), 70 (m 55, f 15; age range 28-8 years; median 58.7 years) out of 248 HNT patients of the Clinic of Cranio-Maxillofacial and Oral Surgery at the University of Zurich, Switzerland, fulfilled the inclusion criteria. Parameters of investigation were the salivary flow rates, possible dental foci and the dental status, oral side effects of radiotherapy, the prophylaxis protocol, and patient's compliance to this protocol. The following time points before during and after IMRT (6 weeks) were analyzed: prior to IMRT, 2-4 weeks, 6 weeks and 3, 6, and 12 months after the onset of radiotherapy.

RESULT

Unstimulated salivary flow rate, pH value of unstimulated salivary, and stimulated salivary flow rate showed a significant reduction over time (p < 0.001). One year after IMRT, both unstimulated and stimulated salivary flow showed a statistically significant lower salivary flow. The number of caries-affected sites per patient was significantly higher for patients with low compliance to the prophylaxis protocol (mean: low compliance 1.36, high compliance 0.26). Almost 75% of the evaluated patients suffered immediate gustatory change, and 47.1% showed signs of radiostomatitis through IMRT.

CONCLUSIONS

High compliance to the prophylaxis protocol during and after radiotherapy is a key factor for the reduction of radiation side effects on dental hard tissue.

CLINICAL RELEVANCE

High compliance to a monitored prophylaxis program is crucial for patients after head and neck surgery.

Cancer of the gingiva

Cancer of the gingiva is a rare disease in the Western World. It most commonly affects elderly population. Because of its rarity, the reporting on the disease is sparse and often grouped with other subsites of oral cancer, which makes conclusions difficult to interpret. The aim of this paper is to review the literature on gingival cancer as a specific subsite of oral cancer and report on published prognostic factors as well as treatment of local and regional disease. We also present differences between gingival cancer subgroups, mandibular and maxillary gingival cancer. In addition, both surgical and oncological treatments are reviewed. It seems that surgery is the preferred initial treatment approach for the majority of patients with gingival cancer, although adjuvant radiation, with or without chemotherapy, is commonly recommended to increase locoregional control.

Role of high dose rate interstitial brachytherapy in early and locally advanced squamous cell carcinoma of buccal mucosa

Background

The study aimed to assess the effect of High Dose Rate (HDR) Interstitial Brachytherapy when used alone or in combination with External Beam Radiotherapy (EBRT), in early and locally advanced squamous cell carcinoma of buccal mucosa.

Materials and methods

Thirty three patients with histologically proven squamous cell carcinoma of the buccal mucosa received high dose rate interstitial brachytherapy either as primary treatment or as a boost from November 2008 to April 2013. Stage I patients received interstitial brachytherapy alone to a dose of 38.50 Gy, 3.5 Gy per fraction, twice daily at six hours apart for 11 fractions. Stage II patients received EBRT to a dose of 50 Gy in 25 fractions of two Gy each followed by brachytherapy boost to 21 Gy, 3.5 Gy per fraction, twice daily at six hours apart for six fractions. Stage III patients received the same radiotherapy schedule (i.e., same EBRT & Brachytherapy schedule) and with addition of Injection Cisplatin 70 mg/m² in three divided doses every three weeks along with EBRT.

Results

Follow up ranged from 12 to 60 months, median follow up was 26 months. Complete response was observed in 28 patients. Five patients had residual disease and were referred for surgical salvage. One patient died of disease progression. Stage I patients had 100% local control, whereas Stage II and Stage III patients had 84.6% and 80% local control respectively.

Conclusion

HDR Interstitial Brachytherapy used either as a primary treatment modality or as a boost in buccal mucosal cancers provides results comparable to that of surgery, with the advantages of organ preservation, better cosmetic and functional outcomes.

Clinical effectiveness, toxicity, and failure patterns of helical tomotherapy for postoperative oral cavity cancer patients

Background

The outcome of postoperative high- and intermediate-risk oral cavity cancer (OCC) patients receiving helical tomotherapy (HT) remains limited.

Materials and methods

Between November 2006 and November 2012, 53 postoperative high- and intermediate-risk OCC patients treated with HT were enrolled.

Results

The 4-year locoregional, local, and regional control rates were 66%, 76.4%, and 94.3%, respectively. The 4-year locoregional control rates of oral tongue and buccal mucosa cancer were 88.3% and 37.1%, respectively (P=0.012). Eleven (20.8%) patients experienced locoregional failure. In-field failure occurred in six of 53 (11.3%) in the primary area and three of 53 (5.7%) in the regional lymph-node area. No marginal failure was noted. Two of 53 (3.8%) experienced out-of-field failure. The rates of grade 3 dermatitis, mucositis, and dysphagia were 11%, 34%, and 13%, respectively. No grade 3 xerostomia was noted. Grade 2 xerostomia was 33% at month 6 and declined to 0 at month 48. A rate of 56% of grade 2 trismus at month 6 was noted, and declined to around 30% after 2 years. No grade 3 trismus was noted after 2 years.

Conclusion

HT as a postoperative modality provided satisfying results, especially for xerostomia and trismus, and was impressive in high- and intermediate-risk OCC patients receiving postoperative HT.

The treatment outcome and radiation-induced toxicity for patients with head and neck carcinoma in the IMRT era: a systematic review with dosimetric and clinical parameters

A descriptive analysis was made in terms of the related radiation induced acute and late mucositis and xerostomia along with survival and tumor control rates (significance level at 0.016, bonferroni correction), for irradiation in head and neck carcinomas with either 2D Radiation Therapy (2DRT) and 3D conformal (3DCRT) or Intensity Modulated Radiation Therapy (IMRT). The mean score of grade > II xerostomia for IMRT versus 2-3D RT was 0.31 ± 0.23 and 0.56 ± 0.23, respectively (Mann Whitney, P < 0.001). The parotid-dose for IMRT versus 2-3D RT was 29.56 ± 5.45 and 50.73 ± 6.79, respectively (Mann Whitney, P = 0.016). The reported mean parotid-gland doses were significantly correlated with late xerostomia (spearman test, rho = 0.5013, P < 0.001). A trend was noted for the superiority of IMRT concerning the acute oral mucositis. The 3-year overall survival for either IMRT or 2-3DRT was 89.5% and 82.7%, respectively (P = 0.026, Kruskal-Wallis test). The mean 3-year locoregional control rate was 83.6% (range: 70-97%) and 74.4 (range: 61-82%), respectively (P = 0.025, Kruskal-Wallis). In conclusion, no significant differences in terms of locoregional control, overall survival and acute mucositis could be noted, while late xerostomia is definitely higher in 2-3D RT versus IMRT. Patients with head and neck carcinoma should be referred preferably to IMRT techniques.

Oral cancer: Current role of radiotherapy and chemotherapy

The term oral cavity cancer (OSCC) constitutes cancers of the mucosal surfaces of the lips, floor of mouth, oral tongue, buccal mucosa, lower and upper gingiva, hard palate and retromolar trigone. Treatment approaches for OSCC include single management with surgery, radiotherapy [external beam radiotherapy (EBRT) and/or brachytherapy], as well as adjuvant systemic therapy (chemotherapy and/or target agents); various combinations of these modalities may also be used depending on the disease presentation and pathological findings. The selection of sole or combined modality is based on various considerations that include disease control probability, the anticipated functional and cosmetic outcomes, tumor resectability, patient general condition, and availability of resources and expertise. For resectable OSCC, the mainstay of treatment is surgery, though same practitioners may advocate for the use of radiotherapy alone in selected "early" disease presentations or combined with chemotherapy in more locally advanced stage disease. In general, the latter is more commonly reserved for cases where surgery may be problematic. Thus, primary radiotherapy ± chemotherapy is usually reserved for patients unable to tolerate or who are otherwise unsuited for surgery. On the other hand, brachytherapy may be considered as a sole modality for early small primary tumor. It also has a role as an adjuvant to surgery in the setting of inadequate pathologically assessed resection margins, as does postoperative external beam radiotherapy ± chemotherapy, which is usually reserved for those with unfavorable pathological features. Brachytherapy can also be especially useful in the re-irradiation setting for persistent or recurrent disease or for a second primary arising within a previous radiation field. Biological agents targeting the epithelial growth factor receptor (EGFR) have emerged as a potential modality in combination with radiotherapy or chemoradiotherapy and are currently under evaluation in clinical trials.

Outcome and patterns of failure after postoperative intensity modulated radiotherapy for locally advanced or high-risk oral cavity squamous cell carcinoma

Background

To determine the outcome and patterns of failure in oral cavity cancer (OCC) patients after postoperative intensity modulated radiotherapy (IMRT) with concomitant systemic therapy.

Methods

All patients with locally advanced (AJCC stage III/IV) or high-risk OCC (AJCC stage II) who underwent postoperative IMRT at our institution between December 2006 and July 2010 were retrospectively analyzed. The primary endpoint was locoregional recurrence-free survival (LRRFS). Secondary endpoints included distant metastasis-free survival (DMFS), overall survival (OS), acute and late toxicities.

Results

Overall 53 patients were analyzed. Twenty-three patients (43%) underwent concomitant chemotherapy with cisplatin, two patients with carboplatin (4%) and four patients were treated with the monoclonal antibody cetuximab (8%).

At a median follow-up of 2.3 (range, 1.1–4.6) years the 3-year LRRFS, DMFS and OS estimates were 79%, 90%, and 73% respectively. Twelve patients experienced a locoregional recurrence. Eight patients, 5 of which had both a flap reconstruction and extracapsular extension (ECE), showed an unusual multifocal pattern of recurrence. Ten locoregional recurrences occurred marginally or outside of the high-risk target volumes. Acute toxicity grades of 2 (27%) and 3 (66%) and late toxicity grades of 2 (34%) and 3 (11%) were observed.

Conclusion

LRRFS after postoperative IMRT is satisfying and toxicity is acceptable. The majority of locoregional recurrences occurred marginally or outside of the high-risk target volumes. Improvement of high-risk target volume definition especially in patients with flap reconstruction and ECE might transfer into better locoregional control.

Evaluation of the trade-offs encountered in planning and treating locally advanced head and neck cancer: intensity-modulated radiation therapy vs dual-arc volumetric-modulated arc therapy

OBJECTIVE

The primary purpose of this study was to assess the practical trade-offs between intensity-modulated radiation therapy (IMRT) and dual-arc volumetric-modulated arc therapy (DA-VMAT) for locally advanced head and neck cancer (HNC).

METHODS

For 15 locally advanced HNC data sets, nine-field step-and-shoot IMRT plans and two full-rotation DA-VMAT treatment plans were created in the Pinnacle(3) v. 9.0 (Philips Medical Systems, Fitchburg, WI) treatment planning environment and then delivered on a Clinac iX (Varian Medical Systems, Palo Alto, CA) to a cylindrical detector array. The treatment planning goals were organised into four groups based on their importance: (1) spinal cord, brainstem, optical structures; (2) planning target volumes; (3) parotids, mandible, larynx and brachial plexus; and (4) normal tissues.

RESULTS

Compared with IMRT, DA-VMAT plans were of equal plan quality (p>0.05 for each group), able to be delivered in a shorter time (3.1 min vs 8.3 min, p<0.0001), delivered fewer monitor units (on average 28% fewer, p<0.0001) and produced similar delivery accuracy (p>0.05 at γ(2%/2mm) and γ(3%/3mm)). However, the VMAT plans took more planning time (28.9 min vs 7.7 min per cycle, p<0.0001) and required more data for a three-dimensional dose (20 times more, p<0.0001).

CONCLUSIONS

Nine-field step-and-shoot IMRT and DA-VMAT are both capable of meeting the majority of planning goals for locally advanced HNC. The main trade-offs between the techniques are shorter treatment time for DA-VMAT but longer planning time and the additional resources required for implementation of a new technology. Based on this study, our clinic has incorporated DA-VMAT for locally advanced HNC.

ADVANCES IN KNOWLEDGE

DA-VMAT is a suitable alternative to IMRT for locally advanced HNC.

Follow up after IMRT in oral cavity cancer: update

PURPOSE

Except for early stages (T1/2 N0), the prognosis for patients with oral cavity cancer (OCC) is known to be worse than for those with pharyngeal carcinoma. While definitive intensity modulated radiation therapy (IMRT)-chemotherapy affords loco-regional control rates (LRC) of approximately 80% in advanced pharyngeal cancer, corresponding rates are reported to be much lower for OCC. The aim of this work was to evaluate loco-regional disease control and overall survival (OAS) in a relatively large OCC patient cohort treated in the IMRT era.

METHODS AND MATERIALS

Between October 2002 and June 2011, 160 OCC patients were treated with curative intention IMRT at our department. 122 patients (76%) were referred with primary disease and 38 patients (24%) with a recurrent OCC at least 3 months after surgery alone. Definitive IMRT was performed in 44/160 patients (28%), whilst 116 patients underwent previous surgery. Simultaneous systemic therapy was administered in 72%.

RESULTS

Patients with postoperative IMRT (+/-systemic therapy) with R0-1 status (n = 99) reached significantly higher LRC/OAS rates than patients following IMRT for macroscopic disease (n = 61), with 84%/80% versus 38%/33% at 3 years, respectively (p < 0.0001). This was found in patients treated for initial, as well as recurrent, disease. Less than 2% persisting grade 3/4 late effects were observed.

CONCLUSIONS

IMRT for R0-1 situations translated into a highly significant superior LRC and OAS compared to the IMRT cohort treated for macroscopic disease. Treatment was well tolerated.

The treatment of oral cancer: an overview for dental professionals

Oral cancer is a serious life-threatening disease. Dental professionals may be the first individuals to identify/suspect these lesions before referring to oral and maxillofacial surgeons and oral medicine specialists. Because the general dentist will likely follow on with the patient's future oral health, it is important that he or she has a basic understanding of the various treatments involved in treating oral malignancies and their respective outcomes. The four main modalities discussed in this review include surgery alone, radiotherapy alone, surgery with radiotherapy, and chemotherapy with or without surgery and radiotherapy. Chemotherapy has become an area of great interest with the introduction of new 'targeted therapies' demonstrating promising results in conjunction with surgery. Despite these results, the toxicities associated with chemotherapy regimens are frequent and can be severe, and therefore may not be suitable for all patients. Treatment modalities have improved significantly over the decades with overall decreases in recurrence rates, improved disease-free and overall survival, and an improved quality of life. Prognosis, however, is still ultimately dependent on the clinical stage of the tumour at the initial diagnosis with respect to size, depth, extent, and metastasis as recurrence rates and survival rates plummet with disease progression.

Impact of tumor volume and systemic therapy on outcome in patients undergoing IMRT for large volume head neck cancer

Background

Former prospective analyses revealed gross tumor volume (GTV) as the most reliable parameter to statistically significantly predict disease control in head neck cancer (HNC) patients treated with definitive intensity modulated radiation therapy (IMRT) +/-concomitant systemic therapy. The most 'unfavourable' subgroup was characterized by total GTV (tGTV) of > 70 cc, translating in ~50 and 65% 3-year disease free (DFS) and overall survival (OAS, vs 68% and 88% in tGTV < 70 cc, p = 0.001 and 0.0001), and ~25% distant spread (vs 6% for tGTV < 70 cc, p < 0.0001).

The aim of this report was to analyze whether there is a subgroup out of patients with tGTV > 70 cc, which only marginally benefits from intensive curative treatment.

Results

Between 03/2002-03/2011, 112 HNC patients with tGTV > 70 cc were definitively irradiated with curative intention. Mean tGTV was 104 cc (71-251). 98/112 (88%) patients underwent systemic therapy. Parameters with potential impact on disease outcome were retrospectively tested. The 3-year local-regional control (LRC), DFS and OAS rates were 61%, 50%, and 58%. The used cut-off value of 130 cc revealed an inverse association between tGTV and outcome. Patients able to undergo any systemic therapy (n = 98, mean tGTV0 103 cc, mean age 60 years) showed a satisfying and significantly superior outcome compared to the subgroup with radiation alone (n = 14, mean tGTV 99 cc, mean age 73 years), with 53% vs 17% 3-year DFS (p = 0.01). Radiation alone for tGTV > 130 cc failed to aim its curative goal in 3/3 patients.

Conclusion

Patients with tGTV > 70 cc unable to undergo any systemic therapy represented a subgroup in which disease control was achievable in < 20% following curatively intended IMRT. Prospective testing of a larger sample size is needed to evaluate, if radiation alone for tGTV >~130 cc fails to meet its curative aim.

Long-term experience in sentinel node biopsy for early oral and oropharyngeal squamous cell carcinoma

OBJECTIVE

Long-term results of sentinel node biopsy (SNB) in early (T1/T2) oral and oropharyngeal squamous cell carcinoma (OSCC) in a single-institution experience.

METHODS

Prospective consecutive cohort analysis of 79 patients (67% male, median age 60 years, age range 34-87 years) included between 2000 and 2006. Lymphatic mapping consisted of preoperative lymphoscintigraphy, single photon emission computed tomography (SPECT/CT), and intraoperative use of a handheld gamma probe. Endpoints of the study were neck control rate, overall (OS), disease-specific (DSS), and disease-free survival (DFS).

RESULTS

Twenty-nine of 79 patients (37%) had positive sentinel nodes (SN). Six of 29 (21%) patients showed isolated tumor cells, 14/29 (48%) micrometastases, and 9/29 (31%) macrometastases. OS, DFS, and DSS at 5 years for the entire cohort were 80, 85, and 87%, for SN-negative patients were 88, 96, and 96%, and for SN-positive patients were 74, 73, and 77%, respectively. Only the difference in DSS achieved statistical significance. The neck control rate after 5 years was 96% in SN-negative and 74% in SN-positive patients. This difference was statistically significant.

CONCLUSIONS

SNB is a safe and accurate staging modality to select patients with clinically stage I/II OSCC with occult lymph node disease for elective neck dissection (END). The promising reported short-term results have been sustained by long-term follow-up. Patients with negative SN and no END achieve an excellent neck control rate which compares favorably with reports on primary END. The neck control rate in SN-negative patients is superior to that in SN-positive patients, which is reflected in superior DSS.

Targeting fibroblast growth factor receptor 3 enhances radiosensitivity in human squamous cancer cells

Conventional therapies including radiation therapy cannot cure squamous cell carcinoma (SCC), and new treatments are clearly required. Our recent studies have shown that SCC cell lines exhibiting radioresistance show significant upregulation of the fibroblast growth factor receptor 3 (FGFR3) gene. We hypothesized that inhibiting FGFR3 would suppress tumor cell radioresistance and provide a new treatment approach for human SCCs. In the present study, we found that RNA interference-mediated FGFR3 depletion in HSC-2 cells, a radioresistant cell line, induced radiosensitivity and inhibited tumor growth. Use of an FGFR3 inhibitor (PD173074) obtained similar results with suppression of the autophosphorylation extracellular signal-regulated kinase pathway in HSC-2 cells and lung cancer cell lines. Moreover, the antitumor growth effect of the combination of PD173074 and radiation in vivo was also greater than that with either drug alone or radiation alone. Our results provided novel information on which to base further mechanistic study of radiosensitization by inhibiting FGFR3 in human SCC cells and for developing strategies to improve outcomes with concurrent radiotherapy.

Treatment of oral cavity squamous cell carcinoma with adjuvant or definitive intensity-modulated radiation therapy

PURPOSE

The optimal management of oral cavity squamous cell carcinoma (OCSCC) typically involves surgical resection followed by adjuvant radiotherapy or chemoradiotherapy (CRT) in the setting of adverse pathologic features. Intensity-modulated radiation therapy (IMRT) is frequently used to treat oral cavity cancers, but published IMRT outcomes specific to this disease site are sparse. We report the Dana-Farber Cancer Institute experience with IMRT-based treatment for OCSCC.

METHODS AND MATERIALS

Retrospective study of all patients treated at Dana-Farber Cancer Institute for OCSCC with adjuvant or definitive IMRT between August 2004 and December 2009. The American Joint Committee on Cancer disease stage criteria distribution of this cohort included 5 patients (12%) with stage I; 10 patients (24%) with stage II (n = 10, 24%); 14 patients (33%) with stage III (n = 14, 33%); and 13 patients (31%) with stage IV. The primary endpoint was overall survival (OS); secondary endpoints were locoregional control (LRC) and acute and chronic toxicity.

RESULTS

Forty-two patients with OCSCC were included, 30 of whom were initially treated with surgical resection. Twenty-three (77%) of 30 surgical patients treated with adjuvant IMRT also received concurrent chemotherapy, and 9 of 12 (75%) patients treated definitively without surgery were treated with CRT or induction chemotherapy and CRT. With a median follow-up of 2.1 years (interquartile range, 1.1-3.1 years) for all patients, the 2-year actuarial rates of OS and LRC following adjuvant IMRT were 85% and 91%, respectively, and the comparable results for definitive IMRT were 63% and 64% for OS and LRC, respectively. Only 1 patient developed symptomatic osteoradionecrosis, and among patients without evidence of disease, 35% experienced grade 2 to 3 late dysphagia, with only 1 patient who was continuously gastrostomy-dependent.

CONCLUSIONS

In this single-institution series, postoperative IMRT was associated with promising LRC, OS, and lower late toxicity rates, and chemoradiotherapy was a successful treatment for patients with high-risk disease. In contrast, outcomes of radiation-based treatment for patients with inoperable locally advanced disease were markedly less successful.

Marginal recurrences after selective targeting with intensity-modulated radiotherapy for oral tongue cancer

BACKGROUND

No universal consensus of optimal radiation target coverage for oral tongue cancer exists, and there is wide variability in practice. Some centers use intensity-modulated radiotherapy (IMRT) to selectively target only certain regions at risk while sparing others; however, patterns of failure after such selective targeting are rarely reported.

METHODS AND RESULTS

We critically examined the location of failure in 4 patients with stage III to IV oral tongue cancer who presented to our department with locoregional recurrence after receiving IMRT with selective radiation targeting at outside institutions. All 4 patients' cancer recurred marginally in regions that were not initially targeted, whereas the regions would have been targeted if comprehensive IMRT targeting had been used. The median time to recurrence was short (3.9 months; range, 1.2-10.1 months).

CONCLUSION

This case series highlights the occurrence of marginal failures after selective targeting with IMRT for oral tongue cancer and cautions against this practice unless further supporting evidence becomes available.

Image-guided intensity modulated radiotherapy with helical tomotherapy for postoperative treatment of high-risk oral cavity cancer

BACKGROUND

The aim of this study was to assess the treatment results and toxicity profiles of helical tomotherapy (HT) for postoperative high-risk oral cavity cancer.

METHODS

From December 6, 2006 through October 9, 2009, 19 postoperative high-risk oral cavity cancer patients were enrolled. All of the patients received HT with (84%) or without (16%) chemotherapy.

RESULTS

The median follow-up time was 17 months. The 2-year overall survival, disease-free survival, locoregional control, and distant metastasis-free rates were 94%, 84%, 92%, and 94%, respectively. The package of overall treatment time > 13 wk, the interval between surgery and radiation ≤ 6 wk, and the overall treatment time of radiation ≤ 7 wk was 21%, 84%, and 79%, respectively. The percentage of grade 3 mucositis, dermatitis, and leucopenia was 42%, 5% and 5%, respectively.

CONCLUSIONS

HT achieved encouraging clinical outcomes for postoperative high-risk oral cavity cancer patients with high compliance. A long-term follow-up study is needed to confirm these preliminary findings.

Marginal misses after postoperative intensity-modulated radiotherapy for head and neck cancer

PURPOSE

To describe the spatial distribution of local-regional recurrence (LRR) among patients treated postoperatively with intensity-modulated radiotherapy (IMRT) for head and neck cancer.

METHODS AND MATERIALS

The medical records of 90 consecutive patients treated by gross total resection and postoperative IMRT for squamous cell carcinoma of the head and neck from January 2003 to July 2009 were reviewed. Sites of disease were the oral cavity (43 patients), oropharynx (20 patients), larynx (15 patients), and hypopharynx (12 patients). Fifty patients (56%) received concurrent chemotherapy.

RESULTS

Seventeen of 90 patients treated with postoperative IMRT experienced LRR, yielding a 2-year estimate of local regional control of 80%. Among the LRR patients, 11 patients were classified as in-field recurrences, occurring within the physician-designated clinical target volume, and 6 patients were categorized as marginal recurrences. There were no out-of-field geographical misses. Sites of marginal LRRs included the contralateral neck adjacent to the spared parotid gland (3 patients), the dermal/subcutaneous surface (2 patients), and the retropharyngeal/retrostyloid lymph node region (1 patient).

CONCLUSIONS

Although the incidence of geographical misses was relatively low, the possibility of this phenomenon should be considered in the design of target volumes among patients treated by postoperative IMRT for head and neck cancer.

IMRT and IGRT in head and neck cancer: Have we delivered what we promised?

Intensity-modulated radiation therapy (IMRT) is a revolutionary new paradigm that aims at improving the therapeutic ratio by increasing the dosegradient between target tissues and surrounding normal structures thereby offering probability of better loco-regional control with decreased risk of complications. IMRT is relatively intolerant to set-up uncertainties, warranting periodic image-guidance, making Image-Guided Radiation Therapy (IGRT) a natural corollary to IMRT. There are several challenges associated with the planning, delivery, and quality assurance of the IMRT and IGRT processes that must be addressed to realize the full potential of such exciting and promising technology. Given the complexities involved, it is quite intuitive to understand that IMRT and IGRT are resource-intensive, demanding increased labor, rigour, and expenses too. Other disadvantages associated with high-precision techniques include potentially increased risk of marginal failures, decreased dose homogeneity, and an increase in total body dose with increased risk of secondary carcinogenesis. The aim of this review is to define the role of IMRT and IGRT in contemporary head and neck oncologic practice through a critical appraisal of pertinent literature. Despite relatively short follow-up and limited clinical outcomes data, the weight of evidence suggests that loco-regional control is not inferior (either comparable or even better) and toxicity lesser with IMRT resulting in potentially improved quality-of-life, prompting the widespread adoption of such technology in community practice. Ongoing clinical trials in head and neck IMRT are currently addressing issues to optimize the IMRT process, adopting functional imaging for dose-painting, and incorporating adaptive re-planning strategies to further improve outcomes.

Outcome in recurrent head neck cancer treated with salvage-IMRT

BACKGROUND

Recurrent head neck cancer (rHNC) is a known unfavourable prognostic condition.The purpose of this work was to analyse our rHNC subgroup treated with salvage-intensity modulated radiation therapy (IMRT) for curable recurrence after initial surgery alone.

PATIENTS

Between 4/2003-9/2008, 44 patients with squamous cell rHNC were referred for IMRT, mean/median 33/21 (3-144) months after initial surgery. None had prior head neck radiation. 41% underwent definitive, 59% postoperative IMRT (66-72.6 Gy). 70% had simultaneous chemotherapy.

METHODS

Retrospective analysis of the outcome following salvage IMRT in rHNC patients was performed.

RESULTS

After mean/median 25/21 months (3-67), 22/44 (50%) patients were alive with no disease; 4 (9%) were alive with disease. 18 patients (41%) died of disease. Kaplan Meier 2-year disease specific survival (DSS), disease free survival (DFS), local and nodal control rates of the cohort were 59/49/56 and 68%, respectively.Known risk factors (advanced initial pTN, marginal initial resection, multiple recurrences) showed no significant outcome differences. Risk factors and the presence of macroscopic recurrence gross tumor volume (rGTV) in oral cavity patients vs others resulted in statistically significantly lower DSS (30 vs 70% at 2 years, p = 0.03). With respect to the assessed unfavourable outcome following salvage treatment, numbers needed to treat to avoid one recurrence with initial postoperative IMRT have, in addition, been calculated.

CONCLUSION

A low salvage rate of only approximately 50% at 2 years was found. Calculated numbers of patients needed to treat with postoperative radiation after initial surgery, in order to avoid recurrence and tumor-specific death, suggest a rather generous use of adjuvant irradiation, usually with simultaneous chemotherapy.

Evidence behind use of intensity-modulated radiotherapy: a systematic review of comparative clinical studies

Since its introduction more than a decade ago, intensity-modulated radiotherapy (IMRT) has spread to most radiotherapy departments worldwide for a wide range of indications. The technique has been rapidly implemented, despite an incomplete understanding of its advantages and weaknesses, the challenges of IMRT planning, delivery, and quality assurance, and the substantially increased cost compared with non-IMRT. Many publications discuss the theoretical advantages of IMRT dose distributions. However, the key question is whether the use of IMRT can be exploited to obtain a clinically relevant advantage over non-modulated external-beam radiation techniques. To investigate which level of evidence supports the routine use of IMRT for various disease sites, we did a review of clinical studies that reported on overall survival, disease-specific survival, quality of life, treatment-induced toxicity, or surrogate endpoints. This review shows evidence of reduced toxicity for various tumour sites by use of IMRT. The findings regarding local control and overall survival are generally inconclusive.