Long-term results of intraoperative presacral electron boost radiotherapy (IOERT) in combination with total mesorectal excision (TME) and chemoradiation in patients with locally advanced rectal cancer

The Use of Intraoperative Radiation Therapy (IORT) in Multimodality Management of Cancer Patients: a Single Institution Experience

BACKGROUND

Intraoperative radiation therapy (IORT) is a highly conformal type of radiation therapy given at time of surgery aiming for better tumor local control. It increases the tumor radiation dose without exceeding normal tissues tolerance doses.

PURPOSE

To assess the feasibility of IORT and short-term toxicities in patients with different cancer sites treated with multidisciplinary protocol including IORT.

PATIENTS AND METHODS

Medical records of cancer patients who received IORT as a part of their multidisciplinary treatment at King Faisal Specialized Hospital and Research center (KFSH&RC), Riyadh, Saudi Arabia, from January 2013 until December 2017 were retrospectively reviewed.

RESULTS

A total of 188 patients with 210 IORT applications were analyzed. Twenty-two patients had two applications at the same time. One hundred sixteen patients were males. Median age at time of diagnosis was 49.5 years (19-77). One hundred thirty-four patients had primary, while 54 cases had recurrent disease. Gastroesophageal cancer and soft tissue sarcoma were the most frequent diagnosis in 49 patients followed by colorectal cancer in 35 patients. Major surgeries with curative intent done in 183 patients (97.3%). Hyperthermic intraperitoneal chemotherapy (HIPEC) was performed in 118 (62.8%) patients. The 30-day postoperative mortality rate was 3.2%. Fifty-four (28.7%) patients develop grades III-IV complications according to Clavien-Dindo grading system.

CONCLUSION

The data presented discusses using of IORT treatment for different malignant tumors as a part of multimodality treatment. IORT seems safe and feasible; however, a longer follow-up period is needed for proper evaluation and to define the role of IORT in a tailored multimodality approach.

The Effect of Intraoperative Radiotherapy on Healing and Complications After Sacrectomy and Immediate Reconstruction

INTRODUCTION

Sacropelvic resection is the treatment of choice for pelvic bone tumors and can be associated with intraoperative electron radiotherapy (IOERT) to optimize local control of the disease. Reconstruction with flaps also is essential to avoid pelvic complications. There is scarcity of publications evaluating outcomes of reconstructive procedures associated with IOERT.

METHODS

A prospective study in 53 patients between 2005 and 2018 was performed. Thirty-four patients received IOERT (group I [GI]) and 19 did not (GII). We examined demographic characteristics, tumor pathology, type of resection and volume of surgical specimen, timing of surgery, IOERT doses, postoperative stay, and complications. We used it for reconstruction rectus abdominis, gluteal, omental and gracilis, superior gluteal artery perforator flap, and free flaps.

RESULTS

Colonic adenocarcinoma and chordoma were the most frequent tumors. The median (interquartile range) IOERT dose was 1250 (1000-1250) cGy; operating time was 10.15 (8.6-14.0) hours versus 6.0 (5.0-13.0) hours, hospital stay was 37 (21.2-63.0) days versus 26.0 (12.0-60.0) days, and volume of surgical specimen was 480.5 (88.7-1488.0) mL versus 400 (220.0-6700.0) mL in GI and GII, respectively. Operating time was significantly longer in GI (P < 0.03). There were significant positive correlations between operating time, hospital stay, and volume of surgical specimen. Main complications were exudative wounds (50% vs 31.5%), wound dehiscence (41.1% vs 31.5%), and seroma (29.4% vs 26.3%) in GI and GII, respectively. Complications were similar to previous studies with or without radiotherapy.

CONCLUSIONS

Under a reconstructive approach, IOERT did not harm flap survival nor increased pelvic complications when compared with similar cases without IOERT.

ESTRO/ACROP IORT recommendations for intraoperative radiation therapy in primary locally advanced rectal cancer

Carcinoma of the rectum is a heterogeneous disease. The clinical spectrum identifies a subset of patients with locally advanced tumours that are close to or involve adjoining structures, such as the sacrum, pelvic sidewalls, prostate or bladder. Within this group of patients categorized as "locally advanced", there is also variability in the extent of disease with no uniform definition of resectability. A practice-oriented definition of a locally advanced tumour is a tumour that cannot be resected without leaving microscopic or gross residual disease at the resection site. Since these patients do poorly with surgery alone, irradiation and chemotherapy have been added to improve the outcome. Intraoperative irradiation (IORT) is a component of local treatment intensification with favourable results in this subgroup of patients. International guidelines (National Comprehensive Cancer Network (NCCN) guidelines) currently recommend the use of IORT for rectal cancer resectable with very close or positive margins, especially for T4 and recurrent cancers. We report the ESTRO-ACROP (European Society for Radiotherapy and Oncology - Advisory Committee on Radiation Oncology Practice) recommendations for performing IORT in primary locally advanced rectal cancer.

Intraoperative Strahlentherapie – Indikationen und Optionen in der Viszeralchirurgie

Hintergrund

Die intraoperative Strahlentherapie (IORT) ermöglicht durch die chirurgische Exposition des Tumors und des Tumorbetts eine hohe Präzision, welche eine hohe Strahlendosis im Bereich des Tumors zulässt und gleichzeitig gesundes Gewebe als den dosislimitierenden Faktor vor Strahlung schützt. Aus diesem Grund bietet die IORT besonders dann einen Vorteil, wenn die lokale Tumorkontrolle das Langzeitüberleben entscheidend beeinflusst und Funktionserhalt ermöglicht.

Ziel der Arbeit

Die in dieser Übersichtsarbeit aufgearbeiteten Erkenntnisse aus der Literaturrecherche erlauben einen evidenzbasierten Umgang hinsichtlich Indikationen und Therapieoptionen der IORT für intraabdominelle Tumoren.

Ergebnisse und Schlussfolgerung

Die Effektivität der IORT kann anhand der vorhandenen Evidenzlage nicht abschließend beurteilt werden, jedoch ist die IORT als Ergänzung der multimodalen Therapie bei (Rezidiv‑)Rektumkarzinomen und Sarkomen aktiv im klinischen Alltag etabliert. Magen- und Pankreaskarzinome stellen weitere Indikationen dar; ergänzende Studien sind jedoch notwendig, um die Rolle der IORT hier klar zu definieren. Ein wesentlicher Faktor, damit für Patienten mit primärem Karzinom und insbesondere für Patienten mit lokalem Rezidiv verbesserte lokale Rezidiv- und Überlebensraten erreicht werden können, scheint die Patientenselektion zu sein.

A Review on the Special Radiotherapy Techniques of Colorectal Cancer

Colorectal cancer is one of the commonest cancers worldwide. Radiotherapy has been established as an indispensable component of treatment. Although conventional radiotherapy provides good local control, radiotherapy treatment side-effects, local recurrence and distant metastasis remain to be the concerns. With the recent technological advancements, various special radiotherapy treatment options have been offered. This review article discusses the recently-developed special radiotherapy treatment modalities for various conditions of colorectal cancer ranging from early stage, locally advanced stage, recurrent, and metastatic diseases. The discussion focuses on the areas of feasibility, local control, and survival benefits of the treatment modalities. This review also provides accounts of the future direction in radiotherapy of colorectal cancer with emphasis on the coming era of personalized radiotherapy.

The Impact of Novel Radiation Treatment Techniques on Toxicity and Clinical Outcomes In Rectal Cancer

Purpose of review

Three-dimensional conformal radiation therapy (3DCRT) has been the standard technique in the treatment of rectal cancer. The use of new radiation treatment technologies such as intensity-modulated radiation therapy (IMRT), proton therapy (PT), stereotactic body radiation therapy (SBRT) and brachytherapy (BT) has been increasing over the past 10 years. This review will highlight the advantages and drawbacks of these techniques.

Recent findings

IMRT, PT, SBRT and BT achieve a higher target coverage conformity, a higher organ at risk sparing and enable dose escalation compared to 3DCRT. Some studies suggested a reduction in gastrointestinal and hematologic toxicities and an increase in the complete pathologic response rate; however, the clinical benefit of these techniques remains controversial.

Summary

The results of these new techniques seem encouraging despite conclusive data. Further trials are required to establish their role in rectal cancer.

Intraoperative radiation therapy (IORT) in soft-tissue sarcoma

Soft-tissue sarcoma (STS) represent a rare tumor entity, accounting for less than 1% of adult malignancies. The cornerstone of curative intent treatment is surgery with free margins, although the extent of the surgical approach has been subject to change in the last decades. Multimodal approaches usually including radiation therapy have replaced extensive surgical procedures in order to preserve functionality while maintaining adequate local control. However, the possibility to apply adequate radiation doses by external beam radiation therapy (EBRT) can be limited in some situation especially in case of directly adjacent organs at risk with low radiation tolerance. Application of at least a part of the total dose via intraoperative radiation therapy (IORT) with a single fraction during the surgical procedure may overcome those limitations, because radiosensitive structures can be moved out of the radiation field resulting in reduced toxicity while the enhanced biological effectivity of the high single dose improves local control. The current review summarizes rationale, techniques, oncological and functional outcomes including possible pitfalls and associated toxicities based on the published literature for IORT focusing on extremity and retroperitoneal STS. In extremity STS, combination of limb-sparing surgery, IORT and pre- or postoperative EBRT with moderate doses consistently achieved excellent local control rates at least comparable to approaches using EBRT alone but usually including patient cohorts with higher proportions of unfavourable prognostic factors. Further on, IORT containing approaches resulted in very high limb preservation rates and good functional outcome, probably related to the smaller high dose volume. In retroperitoneal STS, the combination of preoperative EBRT, surgery and IORT consistently achieved high local control rates which seem superior to surgery alone or surgery with EBRT at least with regard to local control and in some reports even to overall survival. Further on, preoperative EBRT in combination with IORT seems to be superior to the opposite combination with regard to local control and toxicity. No major differences in wound healing disturbances or postoperative complication rates can be observed with IORT compared to non-IORT containing approaches. Neuropathy of major nerves remains a dose limiting toxicity requiring dose restrictions or exclusion from target volume. Gastrointestinal structures and ureters should be excluded from the IORT area whenever possible and the IORT volume should be restricted to the available minimum. Nevertheless, IORT represents an ideal boosting method if combined with EBRT and properly executed by experiences users which should be further evaluated preferably in prospective randomized trials.

Irradiation of Very Locally Advanced and Recurrent Rectal Cancer

Adjuvant therapy with chemoradiation or short-course radiation in addition to improvements in surgical technique has led to improved outcomes for patients with locally advanced rectal cancer. Local recurrence rates of less than 10% and 5-year survival rate of 60% or higher is expected. However, for patients with very locally advanced primary or locally recurrent disease in whom surgical resection is likely to be associated with incomplete resection, survival and disease control rates are poor and standard doses of adjuvant radiation or chemoradiation are relatively ineffective. Dose-escalation approaches with intraoperative radiation (IORT) have been explored in both the primary and recurrent setting. Although high-level evidence is lacking, available data suggest improvements in local and distant control leading to improved survival with IORT approaches. This review summarizes the evidence for dose-escalation approaches with IORT for patients with very locally advanced and recurrent rectal cancer.

Influence of intraoperative radiotherapy (IORT) on perioperative outcome after surgical resection of rectal cancer

BACKGROUND

Intraoperative radiotherapy (IORT) for locally advanced or recurrent rectal cancer as an integral part of multimodal treatment might be an option to reduce local cancer recurrence. The aim of the present study was to determine the influence of IORT on the postoperative outcome and complications rates in the treatment of patients with adenocarcinoma of the rectum in comparison to patients with rectum resection only.

METHODS

A total of 162 patients underwent operation for International Union against Cancer stage III/IV rectal cancer or recurrent rectal cancer at our surgical department between 2004 and 2012. They were divided into two groups depending on whether they received IORT or not. General patient details, tumor, and operation details, as well as perioperative major and minor complications, were registered and compared.

RESULTS

Of the 162 patients treated for stage III/IV rectal cancer, 52 underwent rectal resection followed by IORT. Complication rates were similar in the two groups. Operative time was significantly longer in the IORT group (248 ± 84 vs 177 ± 68 min; p < 0.001). No significant differences were found concerning anastomotic leakage rate, hospital stay, or wound infection rate.

CONCLUSIONS

Intraoperative radiotherapy appears to be a safe treatment option in patients with locally advanced or recurrent rectal cancer with acceptable complication rates. The effect on local recurrence rate has to be estimated in long-term follow-up.

Treatment of stage II-III rectal cancer patients

The role and sequencing of radiotherapy in the management of T3-4 or node-positive rectal cancer has evolved over the last few decades. Given the significant local failure rate following surgery alone, both preoperative and postoperative chemotherapy and radiotherapy have been studied to decrease local and systemic failure and improve survival in these patients. This review discusses current indications and controversies for treatment of stage II-III rectal cancer patients.

Intraoperative radiation therapy reduces local recurrence rates in patients with microscopically involved circumferential resection margins after resection of locally advanced rectal cancer

PURPOSE

Intraoperative radiation therapy (IORT) is advocated by some for patients with locally advanced rectal cancer (LARC) who have involved or narrow circumferential resection margins (CRM) after rectal surgery. This study evaluates the potentially beneficial effect of IORT on local control.

METHODS AND MATERIALS

All surgically treated patients with LARC treated in a tertiary referral center between 1996 and 2012 were analyzed retrospectively. The outcome in patients treated with IORT with a clear but narrow CRM (≤2 mm) or a microscopically involved CRM was compared with the outcome in patients who were not treated with IORT.

RESULTS

A total of 409 patients underwent resection of LARC, and 95 patients (23%) had a CRM ≤ 2 mm. Four patients were excluded from further analysis because of a macroscopically involved resection margin. In 43 patients with clear but narrow CRMs, there was no difference in the cumulative 5-year local recurrence-free survival of patients treated with (n=21) or without (n=22) IORT (70% vs 79%, P=.63). In 48 patients with a microscopically involved CRM, there was a significant difference in the cumulative 5-year local recurrence-free survival in favor of the patients treated with IORT (n=31) compared with patients treated without IORT (n=17) (84 vs 41%, P=.01). Multivariable analysis confirmed that IORT was independently associated with a decreased local recurrence rate (hazard ratio 0.24, 95% confidence interval 0.07-0.86). There was no significant difference in complication rate of patients treated with or without IORT (65% vs 52%, P=.18) CONCLUSION: The current study suggests that IORT reduces local recurrence rates in patients with LARC with a microscopically involved CRM.

T4 rectal cancer: do we always need an exenteration?

The management of rectal cancer has changed dramatically over the last few decades. Due to improvements in the multimodality treatment and the introduction of neoadjuvant chemoradiation, previously irresectable tumours can nowadays be cured by extensive multivisceral resections. These highly complex operations are associated with significant morbidity and mortality. Due to optimization of chemoradiotherapy, the introduction of IORT, increasing knowledge of tumour pathology and patterns of recurrence the need for extensive surgery diminishes. The question arises which patients with T4 rectal cancer really need extensive surgery and who can safely be considered for an organ preserving approach.

Intraoperative radiation therapy opportunities for clinical practice normalization: Data recording and innovative development

BACKGROUND

Intraoperative radiotherapy (IORT) refers to the delivery of a high dose of radiation at the time of surgery.

AIM

To analyze clinical and research-oriented innovative activities developed in a 17-year period using intraoperative electron-radiation therapy (IOeRT) as a component of treatment in a multidisciplinary approach for cancer management.

MATERIALS AND METHODS

From 01/1995 to 03/2012 IOeRT procedures were registered in a specific Hospital-based database. Research and developments in imaging and recording for treatment planning implementation are active since 2006.

RESULTS

1004 patients were treated and 1036 IORT procedures completed. Median age of patients was 61 (range 5 months to 94 years). Gender distribution was male in 54% of cases and female in 46%. Disease status at the time of IORT was 796 (77%) primary and 240 (23%) recurrent. Cancer type distribution included: 62% gastrointestinal, 18% sarcoma, 5% pancreas, 2% paediatric, 3% breast, 77 7% oligotopic recurrences, 2% other. IORT technical characteristics were: Applicator size 5 cm 22%, 6 cm 21%, 7 cm 21%, 8 cm 15%, 9 cm 6%, 10 cm 7% 12 cm 5% 15 cm 3%. Electron energies: 6 MeV 19%, 8 MeV 15%, 10 MeV 15%, 12 MeV 23%, 15 MeV 19%, 18 MeV 6%, other 3%. Multiple fields: 108 (11%). Dose: 7.5 Gy 3%, 10 Gy 35%, 12 Gy 3%, 12.5 Gy 49%, 15 Gy 5%, other 5%.

CONCLUSION

An IORT programme developed in an Academic Hospital based on practice-oriented medical decisions is an attractive interdisciplinary oncology initiative proven to be able to generate an intensive clinical activity for cancer patient quality care and a competitive source of scientific patient-oriented research, development and innovation.

Clinical and technical characteristics of intraoperative radiotherapy. Analysis of the ISIORT-Europe database

BACKGROUND

A joint analysis of clinical data from centres within the European section of the International Society of Intraoperative Radiation Therapy (ISIORT-Europe) was undertaken in order to define the range of intraoperative radiotherapy (IORT) techniques and indications encompassed by its member institutions.

MATERIALS AND METHODS

In 2007, the ISIORT-Europe centres were invited to record demographic, clinical and technical data relating to their IORT procedures in a joint online database. Retrospective data entry was possible.

RESULTS

The survey encompassed 21 centres and data from 3754 IORT procedures performed between 1992 and 2011. The average annual number of patients treated per institution was 42, with three centres treating more than 100 patients per year. The most frequent tumour was breast cancer with 2395 cases (63.8 %), followed by rectal cancer (598 cases, 15.9 %), sarcoma (221 cases, 5.9 %), prostate cancer (108 cases, 2.9 %) and pancreatic cancer (80 cases, 2.1 %). Clinical details and IORT technical data from these five tumour types are reported.

CONCLUSION

This is the first report on a large cohort of patients treated with IORT in Europe. It gives a picture of patient selection methods and treatment modalities, with emphasis on the main tumour types that are typically treated by this technique and may benefit from it.

Research opportunities in intraoperative radiation therapy: the next decade 2013-2023

The reality of intraoperative radiation therapy (IORT) practice is consistent with an efficient and highly precise radiation therapy technique to safely boost areas at risk for local recurrence. Long-term clinical experience has shown that IORT-containing multi-modality regimens appear to improve local disease control, if not survival in many diseases. Research with IORT is a multidisciplinary scenario that covers knowledge from radiation beam adapted development to advance molecular biology for bio-predictability of outcome. The technical parameters employed in IORT procedures are important information to be recorded for quality assurance and clinical results analysis. In addition, specific treatment planning systems for IORT procedures are available, to help in the treatment decision-making process. A systematic revision of opportunities for research and innovation in IORT is reported including radiation beam modulation, delivery, dosimetry and planning; infrastructure and treatment factors; experimental and clinical radiobiology; clinical trials, innovation and translational research development.

Intraoperative radiotherapy in colorectal cancer: systematic review and meta-analysis of techniques, long-term outcomes, and complications

BACKGROUND

The precise contribution of IORT to the management of locally advanced and recurrent colorectal cancer (CRC) remains uncertain. We performed a systematic review and meta-analysis to assess the value of IORT in this setting.

METHODS

Studies published between 1965 and 2011 that reported outcomes after IORT for advanced or recurrent CRC were identified by an electronic literature search. Studies were assessed for methodological quality and design, and evaluated for technique of IORT delivery, oncological outcomes, and complications following IORT. Outcomes were analysed with fixed-effect and random-effect model meta-analyses and heterogeneity and publication bias examined.

RESULTS

29 studies comprising 14 prospective and 15 retrospective studies met the inclusion criteria and were assessed, yielding a total of 3003 patients. The indication for IORT was locally advanced disease in 1792 patients and locally recurrent disease in 1211 patients. Despite heterogeneity in methodology and reporting practice, IORT is principally applied for the treatment of close or positive margins. When comparative studies were evaluated, a significant effect favouring improved local control (OR 0.22; 95% CI = 0.05-0.86; p = 0.03), disease free survival (HR 0.51; 95% CI = 0.31-0.85; p = 0.009), and overall survival (HR 0.33; 95% CI = 0.2-0.54; p = 0.001) was noted with no increase in total (OR 1.13; 95% CI = 0.77-1.65; p = 0.57), urologic (OR 1.35; 95% CI = 0.84-2.82; p = 0.47), or anastomotic complications (OR 0.94; 95% CI = 0.42-2.1; p = 0.98). Increased wound complications were noted after IORT (OR 1.86; 95% CI = 1.03-3.38; p = 0.049).

CONCLUSIONS

Despite methodological weaknesses in the studies evaluated, our results suggest that IORT may improve oncological outcomes in advanced and recurrent CRC.

Intraoperative Electron Radiation Therapy (IOERT) in the management of locally recurrent rectal cancer

BACKGROUND

To evaluate disease control, overall survival and prognostic factors in patients with locally recurrent rectal cancer after IOERT-containing multimodal therapy.

METHODS

Between 1991 and 2006, 97 patients with locally recurrent rectal cancer have been treated with surgery and IOERT. IOERT was preceded or followed by external beam radiation therapy (EBRT) in 54 previously untreated patients (median dose 41.4 Gy) usually combined with 5-Fluouracil-based chemotherapy (89%). IOERT was delivered via cylindric cones with doses of 10-20 Gy. Adjuvant CHT was given only in a minority of patients (34%). Median follow-up was 51 months.

RESULTS

Margin status was R0 in 37%, R1 in 33% and R2 in 30% of the patients. Neoadjuvant EBRT resulted in significantly increased rates of free margins (52% vs. 24%). Median overall survival was 39 months. Estimated 5-year rates for central control (inside the IOERT area), local control (inside the pelvis), distant control and overall survival were 54%, 41%, 40% and 30%. Resection margin was the strongest prognostic factor for overall survival (3-year OS of 80% (R0), 37% (R1), 35% (R2)) and LC (3-year LC 82% (R0), 41% (R1), 18% (R2)) in the multivariate model. OS was further significantly affected by clinical stage at first diagnosis and achievement of local control after treatment in the univariate model. Distant failures were found in 46 patients, predominantly in the lung. 90-day postoperative mortality was 3.1%.

CONCLUSION

Long term OS and LC can be achieved in a substantial proportion of patients with recurrent rectal cancer using a multimodality IOERT-containing approach, especially in case of clear margins. LC and OS remain limited in patients with incomplete resection. Preoperative re-irradiation and adjuvant chemotherapy may be considered to improve outcome.

Laparoscopic abdominoperineal resection with intraoperative radiotherapy for locally advanced low rectal cancer

AIMS

Intraoperative radiotherapy (IORT) for locally advanced rectal cancer as an integral part of multimodal treatment, may lead to reduced local recurrence but it is not routinely used. The aim of this paper is to describe our experience with IORT in the treatment of patients with locally advanced adenocarcinoma of the lower third of the rectum.

MATERIAL AND METHODS

Laparoscopic abdominoperineal amputation of the rectum with intraoperative radiotherapy was performed on 17 patients, 13 men and 4 women, median age 64 years (49-75 years) between 2010-2011. All patients underwent complete therapy according to the treatment protocol.

RESULTS

In one patient, the laparoscopic procedure had to be converted to an open resection. The duration of the surgical procedure with IORT was 185 to 345 min (median 285 min). In 14 cases, the intraoperative dose was 10 Gy and in two patients a dose of 12 Gy was used. There were no severe intraoperative complications. Blood loss ranged from 30 to 500 mL (median 100 mL). There were postoperative complications in 4 patients (23.5%); 2 necessitated surgical reintervention (11.8%). The duration of postoperative hospitalization was 6 to 35 days (median 7 days). In the follow-up of 2 to 16 months (median 12 months), no local recurrence or disease generalization have been found to date.

CONCLUSIONS

The results show the technical feasibility of laparoscopically assisted abdominoperineal amputation of the rectum in combination with IORT in the treatment of locally advanced rectal carcinoma with an acceptable risk of postperative complications.

Multimodal treatment strategies for locally advanced rectal cancer

This review outlines the important multimodal treatment issues associated with locally advanced rectal cancer. Changes to chemotherapy and radiation schema, as well as modern surgical approaches, have led to a revolution in the management of this disease but the morbidity and mortality remains high. Adequate treatment is dependent on precise preoperative staging modalities. Advances in staging via endorectal ultrasound, computed tomography, MRI and PET have improved pretreatment triage and management. Important prognostic factors and their impact for this disease are under investigation. Here we discuss the different treatment options including modern tumor-related surgical approaches, neoadjuvant as well as adjuvant therapies. Further clinical progress will largely depend on the broader implementation of multidisciplinary treatment strategies following the principles of evidence-based medicine.

Intraoperative radiation therapy with the photon radiosurgery system in locally advanced and recurrent rectal cancer: retrospective review of the Cleveland clinic experience

Background

Patients with locally advanced or recurrent rectal cancer often require multimodality treatment. Intraoperative radiation therapy (IORT) is a focal approach which aims to improve local control.

Methods

We retrospectively reviewed 42 patients treated with IORT following definitive resection of a locally advanced or recurrent rectal cancer from 2000–2009. All patients were treated with the Intrabeam® Photon Radiosurgery System (PRS). A dose of 5 Gy was prescribed to a depth of 1 cm (surface dose range: 13.4-23.1, median: 14.4 Gy). Median survival times were calculated using Kaplan-Meier analysis.

Results

Of 42 patients, 32 had recurrent disease (76%) while 10 had locally advanced disease (24%). Eighteen patients (43%) had tumors fixed to the sidewall. Margins were positive in 19 patients (45%). Median follow-up after IORT was 22 months (range 0.2-101). Median survival time after IORT was 34 months. The 3-year overall survival rate was 49% (43% for recurrent and 65% for locally advanced patients). Local recurrence was evaluable in 34 patients, of whom 32% failed. The 1-year local recurrence rate was 16%. Distant metastasis was evaluable in 30 patients, of whom 60% failed. The 1-year distant metastasis rate was 32%. No intraoperative complications were attributed to IORT. Median duration of IORT was 35 minutes (range: 14–39). Median discharge time after surgery was 7 days (range: 2–59). Hydronephrosis after IORT occurred in 10 patients (24%), 7 of whom had documented concomitant disease recurrence.

Conclusions

The Intrabeam® PRS appears to be a safe technique for delivering IORT in rectal cancer patients. IORT with PRS marginally increased operative time, and did not appear to prolong hospitalization. Our rates of long-term toxicity, local recurrence, and survival rates compare favorably with published reports of IORT delivery with other methods.

Efficacy and safety of intraoperative radiotherapy in colorectal cancer: a systematic review

Intraoperative radiotherapy (IORT) has been proposed as an encouraging treatment for colorectal cancer. The aim of this study is to assess the efficacy and safety of IORT for this cancer through a systematic review. Studies located in electronic databases were selected according to established criteria, read and analysed and the results extracted by two independent reviewers. Fifteen studies met the selection criteria. Five-to-six-year local control (LC) was over 80% and 5-year overall survival (OS) was close to 65%. For recurrences, the 5-year overall survival was 30%. The main acute complications were gastrointestinal. Adding IORT to conventional treatment reduces the incidence of local recurrences within the radiation area over 10%. IORT is a safe technique as it does not increase toxicity associated with conventional treatment.

Patterns of local recurrence in locally advanced rectal cancer after intra-operative radiotherapy containing multimodality treatment

BACKGROUND AND PURPOSE

The purpose of this study is to analyze the patterns of local recurrence (LR) after intra-operative radiotherapy (IORT) containing multimodality treatment of locally advanced rectal carcinoma (LARC).

METHODS AND MATERIALS

Two hundred and ninety patients with LARC who underwent multimodality treatment between 1994 and 2006 were studied. For patients who developed LR, the subsite was classified into presacral, postero-lateral, lateral, anterior, anastomotic or perineal. Patient and treatment characteristics were related to subsite of LR.

RESULTS

After 5years, 34 patients (13.2%) developed LR. The most prominent subsite of LR was the presacral subsite. 47% of the local recurrences occurred outside the IORT field. Most recurrences developed when IORT was given dorsally, while least occurred when IORT was given ventrally. Especially after dorsal IORT a high amount of infield recurrences were observed (6 of 8; 75%). In multi-variate analysis tumor distance of more than 5cm from the anal verge and a positive circumferential margin were associated with presacral local recurrence.

CONCLUSIONS

Multimodality treatment is effective in the prevention of local recurrence in LARC. IORT application to the area most at risk is feasible and seems effective in the prevention of local recurrence. Dorsal tumor location results in unfavourable oncologic results.

Radical resection after IORT-containing multimodality treatment is the most important determinant for outcome in patients treated for locally recurrent rectal cancer

Background

The optimal treatment for locally recurrent rectal cancer (LRRC) is still a matter of debate. This study assessed the outcome of LRRC patients treated with multimodality treatment, consisting of neoadjuvant radio (chemo-) therapy, extended resection, and intraoperative radiotherapy.

Methods

One hundred and forty-seven consecutive patients with LRRC who underwent treatment between 1994 and 2006 were studied. The prognostic values of patient-, tumor- and treatment-related characteristics were tested with uni- and multivariate analysis.

Results

Median overall survival was 28 months (range 0-146 months). Five-year overall, disease-free, and metastasis-free survival and local control (OS, DFS, MFS, and LC respectively) were 31.5%, 34.1%, 49.5% and 54.1% respectively. Radical resection (R0) was obtained in 84 patients (57.2%), microscopically irradical resection (R1) in 34 patients (23.1%), and macroscopically irradical resection (R2) in 29 patients (19.7%). For patients with a radical resection median OS was 59 months and the 5-year OS, DFS, MFS, and LC were 48.4%, 52.3%, 65.5% and 68.9%, respectively. Radical resection was significantly correlated with improved OS, DFS, and LC (P < 0.001). Patients who received re-irradiation or full-course radiotherapy survived significantly longer (P = 0.043) and longer without local recurrence (P = 0.038) or metastasis (P < 0.001) compared to patients who were not re-irradiated.

Conclusions

Radical resection is the most significant predictor of improved survival in patients with LRRC. Neoadjuvant radio (chemo-) therapy is the best option in order to realize a radical resection. Re-irradiation is feasible in patients who already received irradiation as part of the primary rectal cancer treatment.

Prototyping a large field size IORT applicator for a mobile linear accelerator

The treatment of large tumors such as sarcomas with intra-operative radiotherapy using a Mobetron is often complicated because of the limited field size of the primary collimator and the available applicators (max Ø100 mm). To circumvent this limitation a prototype rectangular applicator of 80 x 150 mm(2) was designed and built featuring an additional scattering foil located at the top of the applicator. Because of its proven accuracy in modeling linear accelerator components the design was based on the EGSnrc Monte Carlo simulation code BEAMnrc. First, the Mobetron treatment head was simulated both without an applicator and with a standard 100 mm applicator. Next, this model was used to design an applicator foil consisting of a rectangular Al base plate covering the whole beam and a pyramid of four stacked cylindrical slabs of different diameters centered on top of it. This foil was mounted on top of a plain rectangular Al tube. A prototype was built and tested with diode dosimetry in a water tank. Here, the prototype showed clinically acceptable 80 x 150 mm(2) dose distributions for 4 MeV, 6 MeV and 9 MeV, obviating the use of complicated multiple irradiations with abutting field techniques. In addition, the measurements agreed well with the MC simulations, typically within 2%/1 mm.

Radiotherapeutic alternatives for previously irradiated recurrent gliomas

Re-irradiation for recurrent gliomas has been discussed controversially in the past. This was mainly due to only marginal palliation while being associated with a high risk for side effects using conventional radiotherapy.

With modern high-precision radiotherapy re-irradiation has become a more wide-spread, effective and well-tolerated treatment option. Besides external beam radiotherapy, a number of invasive and/or intraoperative radiation techniques have been evaluated in patients with recurrent gliomas.

The present article is a review on the available methods in radiation oncology and summarizes results with respect to outcome and side effects in comparison to clinical results after neurosurgical resection or different chemotherapeutic approaches.

Intraoperative radiation therapy

Intraoperative radiation therapy (IORT) is the delivery of irradiation at the time of an operation. This is performed by different techniques including intraoperative electron beam techniques and high-dose rate brachytherapy. IORT is usually given in combination with external-beam radiation therapy with or without chemotherapy and surgical resection. IORT excludes part or all dose-limiting sensitive structures, thereby increasing the effective dose to the tumor bed (and therefore local control) without significantly increasing normal tissue morbidity. Despite best contemporary therapy, high rates of local failure occur in patients with locally advanced or recurrent rectal cancer, retroperitoneal sarcoma, select gynecologic cancers, and other malignancies. The addition of IORT to conventional treatment methods has improved local control as well as survival in many disease sites in both the primary and locally recurrent disease settings. More recently, there has been interest in the use of IORT as a technique of partial breast irradiation for women with early breast cancer. Given newer and lower cost treatment devices, the use of IORT in clinical practice will likely grow, with increasing integration into the treatment of nonconventional malignancies. Optimally, phase III randomized trials will be carried out to prove its efficacy in these disease sites.

Patterns of failure and local control after intraoperative electron boost radiotherapy to the presacral space in combination with total mesorectal excision in patients with locally advanced rectal cancer

PURPOSE

To evaluate local control and patterns of failure in patients treated with intraoperative electron beam radiotherapy (IOERT) after total mesorectal excision (TME), to appraise the effectiveness of intraoperative target definition.

METHODS AND MATERIALS

We analyzed the outcome of 243 patients with rectal cancer treated with IOERT (median dose, 10 Gy) after TME. Eighty-eight patients received neoadjuvant and 122 patients adjuvant external beam radiotherapy (EBRT) (median dose, 41.4 Gy), and in 88% simultaneous chemotherapy was applied. Median follow-up was 59 months.

RESULTS

Local failure was observed in 17 patients (7%), resulting in a 5-year local control rate of 92%. Only complete resection and absence of nodal involvement correlated positively with local control. Considering IOERT fields, seven infield recurrences were seen in the presacral space, resulting in a 5-year local control rate of 97%. The remaining local relapses were located as follows: retrovesical/retroprostatic (5), anastomotic site (2), promontorium (1), ileocecal (1), and perineal (1).

CONCLUSION

Intraoperative electron beam radiotherapy as part of a multimodal treatment approach including TME is a highly effective regimen to prevent local failure. The presacral space remains the site of highest risk for local failure, but IOERT can decrease the percentage of relapses in this area.