Intraoperative radiotherapy for pre-irradiated head and neck cancer

Reirradiation of head and neck squamous cell carcinomas: a pragmatic approach, part II: radiation technique and fractionations

INTRODUCTION

Reirradiation (reRT) of local recurrent/second primary tumors of the head and neck represents a potential curative treatment for patients not candidate to a salvage surgery. Aim of the present study is to summarize literature data on modern radiation techniques and fractionations used in this setting of patients.

MATERIALS AND METHODS

A narrative review of the literature was conducted on three topics: (1) target volume delineation (2) reRT dose and techniques and (3) ongoing studies. Patients treated with postoperative reRT and palliative intent were not considered for the current analysis.

RESULTS

Recommendations on the target volume contouring have been reported. 3D-Conformal Radiotherapy, Intensity Modulated Radiotherapy, Stereotactic body Radiotherapy Intraoperative Radiotherapy, Brachytherapy and Charged Particles have been analyzed in terms of indication and fractionation in the field of reRT. Ongoing studies on the topic have been reported for IMRT and Charged Particles. Moreover, according to literature data a stepwise approach has been proposed aiming to provide a useful tool to select patients candidate to a curative reRT in daily clinical practice. Two clinical cases were also provided for its application.

CONCLUSION

Different radiation techniques and fractionations can be used for a second course of radiotherapy in patients with recurrent/second primary tumor of head and neck region. Tumor characteristics as well as radiobiological considerations should be take into account to define the best reRT approach.

Systematic review of intraoperative radiation therapy for head and neck cancer

Multidisciplinary treatments with surgery, radiation therapy, and chemotherapy are the cornerstones in the management of locally advanced head and neck malignancies. In most cases, radiation is delivered via external beam radiation therapy (EBRT). Intraoperative radiation therapy (IORT), on the other hand, is the delivery of precise doses of radiation to selected target volumes within the exposed surgical field while at the operating room. Most studies on its use on head and neck cancers are limited to single-institutional retrospective case series. We performed a systematic review to consolidate the existing literature on IORT for head and neck malignancies. Fifty-two studies representing a mixed population of 2,389 patients were included in this review. IORT via electrons (intraoperative electron radiation therapy), brachytherapy (intraoperative high dose-rate brachytherapy) or photons was administered in numerous settings, but most commonly as part of a reirradiation regimen following salvage surgery for recurrent tumours. Often, additional EBRT was also planned postoperatively. This review illustrates that IORT is a promising treatment modality in head and neck cancer. Multiple single-institutional studies spanning several decades have demonstrated benefit in terms of local control with reasonable toxicity. However, randomised trials comparing it with current standards of care are still needed.

A prospective, single-arm, phase II clinical trial of intraoperative radiotherapy using a low-energy X-ray source for local advanced Laryngocarcinoma (ILAL): a study protocol

BACKGROUND

Laryngocarcinoma (LC), in most cases a squamous cell carcinoma, accounts for 1 ~ 5% of the incidence of all tumors. At present, laryngocarcinoma is mainly managed with the integration of surgery and radio- and chemo-therapies. The current development trend of treatment is to improve the local control rate of tumor and the quality of life of patients. Intraoperative radiation therapy (IORT) is a radiotherapy that delivers single high dose irradiation at a close range to the tumor bed during the surgical operation process. It has particular radiobiological advantages in protecting normal surrounding tissues by directly applying the irradiation dose to the high-risk tumor bed area. Two forms of IORT, i.e., high dose rate (HDR) brachytherapy and external beam radiotherapy (EBRT, including electron and photono IORT), had been studied before the treatment of head and neck tumors (including laryngocarcinoma). However, no relevant assessment had been carried out on 50KV low-energy X-ray. We are convinced by certain arguments that the application of low-energy X-ray for intraoperative local radiotherapy of laryngocarcinoma can not only achieve the therapeutic effect of IORT but also reduce the incidence of high-energy irradiation related toxic and side effects. The purpose of this study is to observe the safety and short-term efficacy of IORT when used in conjunction with standard of care for the treatment of local advanced laryngocarcinoma (LAL).

METHODS/DESIGN

In consideration of the applications of precise targeted IORT in oncosurgery and in line with the application range and reference clinical medical guidances approved by SFDA (ZEISS radiosurgical operation system has been used for the treatment of solid tumors since 31 December, 2013 with an approval from SFDA), we have preliminarily planned the tumors suitable for IORT, determined the members of MDT in our hospital, improved the MDT diagnosis and treatment processes for the tumors, established the standards, indications and contraindications for the application of IORT, determined the indicators to be observed after the treatment of tumors with surgical operations plus IORT, and carried out follow-up visits and statistical analysis. This is a single-arm, prospective Phase II clinical trial of the treatment of LAL patients with IORT + EBRT. The study subjects are followed up for statistics and information of their acute/chronic toxic reactions and local control rate, DFS, and OS etc. The safety and short-term efficacy of the application of IORT as SIB for the treatment of LAL. The sample size of the study is 125 subjects.

DISCUSSION

The safety and efficacy of IORT for the treatment of head and neck cancers have been proven in studies by multiple institutions (1-3). The purpose of this study is to investigate the maximum safe dose and short-term efficacy of IORT for providing a theoretical basis for clinical trials.

TRIAL REGISTRATION

Trial registration: Clinicaltrials.gov , NCT04278638. Registered 18 February 2020 - prospectively registered, https://clinicaltrials.gov/ct2/show/NCT04278638.

The American Brachytherapy Society consensus statement on intraoperative radiation therapy

PURPOSE

Although radiation therapy has traditionally been delivered with external beam or brachytherapy, intraoperative radiation therapy (IORT) represents an alternative that may shorten the course of therapy, reduce toxicities, and improve patient satisfaction while potentially lowering the cost of care. At this time, there are limited evidence-based guidelines to assist clinicians with patient selection for IORT. As such, the American Brachytherapy Society presents a consensus statement on the use of IORT.

METHODS

Physicians and physicists with expertise in intraoperative radiation created a site-directed guideline for appropriate patient selection and utilization of IORT.

RESULTS

Several IORT techniques exist including radionuclide-based high-dose-rate, low-dose-rate, electron, and low-energy electronic. In breast cancer, IORT as monotherapy should only be used on prospective studies. IORT can be considered in the treatment of sarcomas with close/positive margins or recurrent sarcomas. IORT can be considered in conjunction with external beam radiotherapy for retroperitoneal sarcomas. IORT can be considered for colorectal malignancies with concern for positive margins and in the setting of recurrent gynecologic cancers. For thoracic, head and neck, and central nervous system malignancies, utilization of IORT should be evaluated on a case-by-case basis.

CONCLUSIONS

The present guidelines provide clinicians with a summary of current data regarding IORT by treatment site and guidelines for the appropriate patient selection and safe utilization of the technique. High-dose-rate, low-dose-rate brachytherapy methods are appropriate when IORT is to be delivered as are electron and low-energy based on the clinical scenario.

Intraoperative Radiation Therapy: A Promising Treatment Modality in Head and Neck Cancer

Every year, almost 62,000 are diagnosed with a head and neck cancer (HNC) and 13,000 will succumb to their disease. In the primary setting, intraoperative radiation therapy (IORT) can be used as a boost in select patients in order to optimize local control. Addition of external beam radiation to limited volumes results in improved disease control over surgery and IORT alone. In the recurrent setting, IORT can improve outcomes from salvage surgery especially in patients previously treated with external beam radiation. The use of IORT remains limited to select institutions with various modalities being currently employed including orthovoltage, electrons, and high-dose rate brachytherapy. Practically, execution of IORT requires a coordinated effort and careful planning by a multidisciplinary team involving the head and neck surgeon, radiation oncologist, and physicist. The current review summarizes common uses, outcomes, toxicities, and technical aspects of IORT in HNC patients.

Intraoperative radiation therapy (IORT) in head and neck cancer: A systematic review

BACKGROUND

Multimodality therapy constitutes the standard treatment of advanced and recurrent head and neck cancer. Since locoregional recurrence comprises a major obstacle in attaining cure, the role of intraoperative radiation therapy (IORT) as an add-on in improving survival and local control of the disease has been investigated. IORT allows delivery of a single tumoricidal dose of radiation to areas of potential residual microscopic disease while minimizing doses to normal tissues. Advantages of IORT include the conformal delivery of a large dose of radiation in an exposed and precisely defined tumor bed, minimizing the risk of a geographic miss creating the potential for subsequent dose reduction of external beam radiation therapy (EBRT). This strategy allows for shortening overall treatment time and dose escalation. The aim of this review is to summarize recent published work on the use of IORT as an adjuvant modality to treat common head and neck cancer in the primary or recurrent setting.

METHODS

We searched the Medline, Scopus, Ovid, Cochrane, Embase, and ISI Web of Science databases for articles published from 1980 up to March 2016.

RESULTS

Based on relevant publications it appears that including IORT in the multimodal treatment may contribute to improved local control. However, the benefit in overall survival is not so clear.

CONCLUSION

IORT seems to be a safe, promising adjunct in the management of head and neck cancer and yet further well organized clinical trials are required to determine its role more precisely.

Intraoperative radiotherapy for parotid cancer: a single-institution experience

PURPOSE

Our practice policy has been to provide intraoperative radiotherapy (IORT) at resection to patients with head-and-neck malignancies considered to be at high risk of recurrence. The purpose of the present study was to review our experience with the use of IORT for primary or recurrent cancer of the parotid gland.

METHODS AND MATERIALS

Between 1982 and 2007, 96 patients were treated with gross total resection and IORT for primary or recurrent cancer of the parotid gland. The median age was 62.9 years (range, 14.3-88.1). Of the 96 patients, 33 had previously undergone external beam radiotherapy as a component of definitive therapy. Also, 34 patients had positive margins after surgery, and 40 had perineural invasion. IORT was administered as a single fraction of 15 or 20 Gy with 4-6-MeV electrons. The median follow-up period was 5.6 years.

RESULTS

Only 1 patient experienced local recurrence, 19 developed regional recurrence, and 12 distant recurrence. The recurrence-free survival rate at 1, 3, and 5 years was 82.0%, 68.5%, and 65.2%, respectively. The 1-, 3-, and 5-year overall survival rate after surgery and IORT was 88.4%, 66.1%, and 56.2%, respectively. No perioperative fatalities occurred. Complications developed in 26 patients and included vascular complications in 7, trismus in 6, fistulas in 4, radiation osteonecrosis in 4, flap necrosis in 2, wound dehiscence in 2, and neuropathy in 1. Of these 26 patients, 12 had recurrent disease, and 8 had undergone external beam radiotherapy before IORT.

CONCLUSIONS

IORT results in effective local disease control at acceptable levels of toxicity and should be considered for patients with primary or recurrent cancer of the parotid gland.

Second salvage surgery for re-recurrent oral cavity and oropharynx carcinoma

BACKGROUND

Salvage surgery is considered the best treatment approach for patients with recurrent oral carcinoma. Unfortunately, 50% to 60% of the patients who undergo salvage surgery will develop further locoregional recurrence, and they are not usually considered for further treatment. Our aim in this study was to report our experience with a second salvage surgery for selected patients with re-recurrent oral cavity and oropharyngeal squamous cell carcinoma (SCC).

METHODS

Forty-one patients underwent a second salvage surgical procedure, with curative intention for re-recurrent oral cancer. The surgical treatment used was wide local resection in 34 cases, neck dissection in 9 cases, and isolated neck dissection in 7 cases.

RESULTS

Cancer-specific survival (CSS) rate in 3 years was at 20%. Patients with re-recurrence in <6 months presented 3-year CSS null, whereas patients with re-recurrence after 6 months presented 3-year CSS of 32.3% (p = .007).

CONCLUSION

Second salvage surgery can be considered a potentially curative therapeutic approach for a selected group of patients with re-recurrent oral SCC. The disease-free interval was the main clinical factor associated with the prognosis.

Intraoperative radiotherapy (IORT) with low-energy photons as a boost in patients with early-stage oral cancer with the indications for postoperative radiotherapy : treatment feasibility and preliminary results

PURPOSE

To evaluate the feasibility and preliminary results of intraoperative radiotherapy (IORT) with low-energy photons as a boost in patients with early-stage oral cancer with the indications for postoperative radiotherapy.

PATIENTS AND METHODS

Between 2003 and 2006, 16 patients with early-stage cancer of mobile tongue (n = 10 [63%]) or floor of the mouth (n = 6 [37%]) treated at Maria Skłodowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice Branch, Poland, were evaluated for IORT boost with the INTRABEAM®System (Carl Zeiss Surgical GmbH; IORT-PRS) because of the high risk of local recurrence due to positive margins on frozen pathologic section. After tumor resection, the applicator was positioned in the tumor bed. The applicator's diameter (range: 1.5-5 cm) was selected to encompass high-risk area of tumor recurrence. The dose (5 Gy, 7 Gy, or 7.5 Gy) was applied according to tumor volume and bone proximity. External-beam radiotherapy (EBRT) was provided to the tumor bed in all patients (50 Gy) and to the nodal area, when needed. Toxicity and local tumor control were assessed.

RESULTS

Median follow-up was 36 months. IORT did not increase acute mucosal reaction. Local tumor control was found in all cases. Early mucosal reaction did not exceed 3 according to the RTOG scale and healed in median time of 35 days after completion of EBRT. No late adverse effects were observed.

CONCLUSION

This preliminary report has demonstrated the feasibility of IORT-PRS for patients with early oral cancer with the indications for postoperative radiotherapy. This method may be considered an alternative boost technique, although additional studies are needed to establish long-term results in a larger group of patients.

High-dose-rate intraoperative radiation therapy for recurrent head-and-neck cancer

PURPOSE

To report the use of high-dose-rate intraoperative radiation therapy (HDR-IORT) for recurrent head-and-neck cancer (HNC) at a single institution.

METHODS AND MATERIALS

Between July 1998 and February 2007, 34 patients with recurrent HNC received 38 HDR-IORT treatments using a Harrison-Anderson-Mick applicator with Iridium-192. A single fraction (median, 15 Gy; range, 10-20 Gy) was delivered intraoperatively after surgical resection to the region considered at risk for close or positive margins. In all patients, the target region was previously treated with external beam radiation therapy (median dose, 63 Gy; range, 24-74 Gy). The 1- and 2-year estimates for in-field local progression-free survival (LPFS), locoregional progression-free survival (LRPFS), distant metastases-free survival (DMFS), and overall survival (OS) were calculated.

RESULTS

With a median follow-up for surviving patients of 23 months (range, 6-54 months), 8 patients (24%) are alive and without evidence of disease. The 1- and 2-year LPFS rates are 66% and 56%, respectively, with 13 (34%) in-field recurrences. The 1- and 2-year DMFS rates are 81% and 62%, respectively, with 10 patients (29%) developing distant failure. The 1- and 2-year OS rates are 73% and 55%, respectively, with a median time to OS of 24 months. Severe complications included cellulitis (5 patients), fistula or wound complications (3 patients), osteoradionecrosis (1 patient), and radiation-induced trigeminal neuralgia (1 patient).

CONCLUSIONS

HDR-IORT has shown encouraging local control outcomes in patients with recurrent HNC with acceptable rates of treatment-related morbidity. Longer follow-up with a larger cohort of patients is needed to fully assess the benefit of this procedure.

Recurrent salivary gland carcinomas treated by surgery with or without intraoperative radiation therapy

BACKGROUND

The optimal treatment for patients with locally recurrent carcinomas of the salivary glands is unclear.

METHODS

Ninety-nine patients underwent salvage surgery for locally recurrent salivary gland carcinomas. Eighty-one (82%) had previously received radiation. Thirty-seven patients (37%) received intraoperative radiation therapy (IORT) to a median dose of 15 Gy (range, 12-18 Gy) at the time of salvage.

RESULTS

The 1-, 3-, and 5-year estimates of local control after salvage surgery were 88%, 75%, and 69%, respectively. A Cox proportional hazard model identified positive margins (0.01) and the omission of IORT (p = .001) as independent predictors of local failure. The 5-year overall survival was 34%. Distant metastasis was the most common site of subsequent failure, occurring in 42% of patients.

CONCLUSIONS

IORT significantly improves disease control for patients with locally recurrent carcinomas of the salivary glands. The high rate of distant metastasis emphasizes the need for effective systemic therapies.

Feasibility of flap reconstruction in conjunction with intraoperative radiation therapy for advanced and recurrent head and neck cancer

BACKGROUND

Radiation is a known risk factor for poor wound healing. Patients undergoing intraoperative radiation therapy (IORT) typically receive higher cumulative doses to their wound beds than patients treated with conventional radiation therapy. We review our experience with IORT in patients undergoing resection of head and neck cancer and flap reconstruction. Logistics of delivery and outcomes are discussed.

METHODS

A retrospective chart review was performed on all patients at Beth Israel Medical Center who underwent IORT for head and neck cancer between 2000 and 2007. Twenty-one patients receiving 22 treatments involving flap reconstruction were identified. The results of these reconstructions were evaluated for complications and functional outcome.

RESULTS

All patients had complex surgical wounds of the face, upper aerodigestive tract, or neck who received IORT in conjunction with pedicled or free flap closure. Twenty-five flaps in 21 patients were performed in the setting of IORT. All patients received between 10 and 15 Gy of IORT administered directly to the wound bed. There were no perioperative mortalities. Wound breakdown occurred in three cases, all of which were treated successfully by operative revision. Functionally, most patients did well and performed similarly to historic controls for their type of reconstruction.

CONCLUSIONS

Reconstruction using flaps in the context of IORT can be achieved with expectation of good wound healing in the majority of cases despite heavy cumulative doses of radiation to recipient wound beds.

Intraoperative radiation therapy for recurrent head-and-neck cancer: the UCSF experience

PURPOSE

To review a single-institutional experience with the use of intraoperative radiation therapy (IORT) for recurrent head-and-neck cancer.

METHODS AND MATERIALS

Between 1991 and 2004, 137 patients were treated with gross total resection and IORT for recurrence or persistence of locoregional cancer of the head and neck. One hundred and thirteen patients (83%) had previously received external beam radiation as a component of definitive therapy. Ninety-four patients (69%) had squamous cell histology. Final surgical margins were microscopically positive in 56 patients (41%). IORT was delivered using either a modified linear accelerator or a mobile electron unit and was administered as a single fraction to a median dose of 15 Gy (range, 10-18 Gy). Median follow-up among surviving patients was 41 months (range, 3-122 months).

RESULTS

The 1-year, 2-year, and 3-year estimates of in-field control after salvage surgery and IORT were 70%, 64%, and 61%, respectively. Positive margins at the time of IORT predicted for in-field failure (p = 0.001). The 3-year rates of locoregional control, distant metastasis-free survival, and overall survival were 51%, 46%, and 36%, respectively. There were no perioperative fatalities. Complications included wound infection (4 patients), orocutaneous fistula (2 patients), flap necrosis (1 patient), trismus (1 patient), and neuropathy (1 patient).

CONCLUSIONS

Intraoperative RT results in effective disease control with acceptable toxicity and should be considered for selected patients with recurrent or persistent cancers of the head and neck.

Intraoperative radiation therapy in the multimodality approach to upper aerodigestive tract cancer

The cure rate of operable lung cancer and locally advanced head and neck cancer remains suboptimal, with a limited rate of local control despite improvements in the surgical removal of primary tumors and in methods for mediastinal lymph node dissection, in particular. The efficacy of adjuvant therapy, such as EBRT, has improved, and the immediate efficacy of new chemotherapeutic drugs is increasingly significant, although local recurrences remain frequent. Locoregional failure is not uncommon in upper aerodigestive tract cancers. Factors limiting radiocurability for locally advanced (stage III) lung cancer include mediastinal intolerance of irradiation (high risk of mediastinal fibrosis, which increases exponentially when levels of much more than 50 Gy are administered to the whole mediastinum) and the very high radiosensitivity of the healthy lung, which can develop fibrosis with relatively small or moderate doses starting at 18 to 20 Gy, and even more frequently when larger volumes are irradiated. Head and neck neoplasms are less difficult sites in which to administer doses of up to 70 Gy of external beam radiotherapy initially, but, like locoregionally recurrent lung cancers, they are not easily reirradiated with tumoricidal doses of EBRT. For these reasons, IORT seems to be a good option for increasing local control, because areas of [figure: see text] residual microscopic disease may be irradiated using IOERT approaches without affecting critical organs to the same extent. In addition, careful patient selection is paramount. Combined modality treatment regimens incorporating IORT may benefit patients with locally advanced disease. The ability of IORT to sterilize microscopic residual disease can enhance the "completeness" of resection and thus, theoretically, improve local control. Although distant disease dissemination remains by far the overriding issue, as newer effective agents emerge, local failure will continue to be a problem. Preliminary studies have demonstrated that IORT can be administered to patients who have locally advanced NSCLC and head and neck cancer, in the context of aggressive combined modality therapy, and is generally well tolerated. Long-term efficacy and benefit can only be determined in the setting of carefully designed clinical trials. (See the article by Thomas and Merrick elsewhere in this issue for further discussion of this topic.) Several relatively small, single-institution pilot studies exploring the utility and benefit of IORT for locally advanced upper aerodigestive tract cancers have been conducted. Clear conclusions have been difficult to determine because of the mixing of disease stages, varying degrees and completeness of surgical resection, varying radiation doses, different schemas, and other factors. Yet, given the major morbidity and mortality associated with locally recurrent lung cancer, methods of improving local control need to be pursued and refined. Encouraging preliminary data suggest that IOERT can be safely administered and may benefit local control. Based on several centers' expertise in the combined modality treatment of locally advanced lung cancer and familiarity with IORT, the UCSF Thoracic Oncology Program has proposed a multicenter phase 2 study incorporating IORT in a combined multimodality treatment schema for patients who have completely resected locally advanced stage IIIA and IIIB NSCLC (nonpleural effusion, non-N3) (Fig. 1). It is hoped that this study will commence in the upcoming year.