High dose rate intraoperative radiation therapy (HDR-IORT) as part of the management strategy for locally advanced primary and recurrent rectal cancer

Intensification of Local Therapy With High Dose Rate, Intraoperative Radiation Therapy (HDR-IORT) and Extended Resection for Locally Advanced and Recurrent Colorectal Cancer

BACKGROUND

We report our long-term experience with high dose rate intraoperative radiotherapy (HDR-IORT) in a single, quaternary institution.

PATIENTS/METHODS

From 2004 to 2020, 60 HDR-IORT procedures for locally advanced colorectal cancer (LACC) and 81 for locally recurrent colorectal cancer (LRCC) were done in our institution. Preoperative radiotherapy was done prior to majority of the resections (89%, 125/141). Sixty-nine percent (58/84) of the resections involving pelvic exenterations had >3 en bloc organs resected. HDR-IORT was delivered using a Freiburg applicator. A single 10 Gy fraction was delivered. Margin status was R0 and R1 in 54% (76/141) and 46% (65/141) of the resections, respectively.

RESULTS

With a median follow-up time of 4 years, 3-, 5-, and 7- year, overall survival (OS) rates were 84%, 58%, and 58% for LACC and 68%, 41%, and 37% for LRCC, respectively. Local progression-free survival (LPFS) rates were 97%, 93%, and 93% for LACC and 80%, 80%, 80% for LRCC, respectively. For the LRCC group, an R1 resection was associated with worse OS, LPFS, and progression-free survival (PFS), preoperative EBRT was associated with improved LPFS and PFS, and ≥2 years disease-free interval was associated with improved PFS. The most common severe adverse events were postoperative abscess (n = 25) and bowel obstruction (n = 11). There were 68 grade 3 to 4 and no grade 5 adverse events.

CONCLUSIONS

Favorable OS and LPFS can be achieved for LACC and LRCC with intensive local therapy. In patients with risk factors for poorer outcomes, optimization of EBRT and IORT, surgical resection, and systemic therapy are required.

Intraoperative Radiotherapy in Brain Malignancies: Indications and Outcomes in Primary and Metastatic Brain Tumors

Despite the continued controversy over defining an optimal delivery mechanism, the critical role of adjuvant radiation in the management of surgically resected primary and metastatic brain tumors remains one of the universally accepted standards in neuro-oncology. Local disease control still ranks as a significant predictor of survival in both high-grade glioma and treated intracranial metastases with radiation treatment being essential in maximizing tumor control. As with the emergence and eventual acceptance of cranial stereotactic radiosurgery (SRS) following an era dominated by traditional radiotherapy, evidence to support the use of intraoperative radiotherapy (IORT) in brain tumors requiring surgical intervention continues to accumulate. While the clinical trial strategies in treating glioblastoma with IORT involve delivery of a boost of cavitary radiation prior to the planned standard external beam radiation, the use of IORT in metastatic disease offers the potential for dose escalation to the level needed for definitive adjuvant radiation, eliminating the need for additional episodes of care while providing local control equal or superior to that achieved with SRS in a single fraction. In this review, we explore the contemporary clinical data on IORT in the treatment of brain tumors along with a discussion of the unique dosimetric and radiobiological factors inherent in IORT that could account for favorable outcome data beyond those seen in other techniques.

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.

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.

Intraoperative radiation therapy for rectal cancer and recurrent intra-abdominal sarcomas

PURPOSE

The aim of this study was to evaluate the effect of high-dose-rate intraoperative radiation therapy (HDR-IORT) in a multimodality treatment on the local control (LC) and the overall survival (OS) rate in locally advanced rectal cancer (LARC), locally recurrent rectal cancer (LRRC) and recurrent intra-abdominal sarcomas (RS).

MATERIALS AND METHODS

A retrospective analysis was performed on 27 patients who were treated with radical resection and HDR-IORT between April 2007 and January 2017. Patient, tumor and surgical characteristics were analyzed and the perioperative (<30 days) and long-term complications (>30 days) were assessed and graded.

RESULTS

None of the patients with LARC (n = 4) developed a local recurrence and all patients were still alive at the end of the follow-up. The LC rates of LRRC (n = 17) after one and three years were respectively 48% and 40% and the one, three and five years OS were respectively 93%, 62% and 44%. For RS (n = 6), the LC rates after one and three years were both 33% and the one and three years OS rate were respectively 83% and 46%.

CONCLUSIONS

The results of our study show that HDR-IORT could be a valuable asset in the multimodality management of LARC, LRRC and RS.

Quality Control of Radiation Delivery for Lower Gastrointestinal Cancers

OPINION STATEMENT

Assessing the quality of health care delivered is a priority across medical specialties, but it is particularly critical for radiation oncology, a field with rapid introduction of new technologies and treatment paradigms. Deviation from acceptable standards can lead to delivery of inferior therapies and medical errors that can directly compromise patient clinical outcome, thus leading to disparities in quality of care. Professional oncologic specialty societies often take ownership of standardizing best practices by issuing evidence-based disease-specific consensus guidelines. They also inform quality indicators that are set as requirements for accreditation, maintenance of certification, and reimbursement. Cooperative groups also create benchmarks for quality radiation therapy through design of clinical protocols that set standard-of-care treatment practices. Pelvic radiotherapy for colorectal and anal cancers has undergone a significant transformation in radiation planning and delivery including increased complexity in contour segmentation with a transition from three-dimensional to intensity-modulated radiation therapy (IMRT). Compliance with quality metrics proposed in national consensus guidelines and participation in clinical trials help keep practicing radiation oncologists up-to-date with advances in our field and well-trained to provide safe and effective high-value care.

Dosimetric Evaluation of a Flexible Dual Balloon-Constructed Applicator in Treating Anorectal Cancer

Background and Purpose:

Materials and Methods:

Results:

Conclusion:

Intraoperative implantation of a mesh of directional palladium sources (CivaSheet): Dosimetry verification, clinical commissioning, dose specification, and preliminary experience

PURPOSE

To present the clinical commissioning of a novel ¹⁰³Pd directional brachytherapy device (CivaSheet) for intraoperative radiation therapy.

METHODS AND MATERIALS

Clinical commissioning for the CivaSheet consisted of establishing: (1) source strength calibration capabilities, (2) experimental verification of TG-43 dosimetry parameters, (3) treatment planning system validation, and (4) departmental practice for dose specification and source ordering. Experimental verification was performed in water with radiochromic film calibrated with a 37 kVp X-ray beam. Percentage difference ([measurements - calculation]/calculation) and distance to agreement (difference between film-to-source distance and distance that minimized the percentage difference) were calculated. Nomogram values (in U/100 Gy) for all configurations (up to 20 × 20 sources) were calculated for source ordering. Clinical commissioning was used on patients enrolled in an ongoing Institutional Review Board-approved protocol.

RESULTS

A source calibration procedure was established, and the treatment planning system was commissioned within standard clinical uncertainties. Percentage dose differences (distances to agreement) between measured and calculated doses were 8.6% (-0.12 mm), 0.6% (-0.01 mm), -6.4% (0.22 mm), and -10.0% (0.44 mm) at depths of 2.3, 5.1, 8.0, and 11.1 mm, respectively. All differences were within the experimental uncertainties. Nomogram values depended on sheet size and spatial extent. A value of 2.4U/100 Gy per CivaDot was found to satisfy most cases, ranging from 2.3 to 3.3U/100 Gy. Nomogram results depended on elongation of the treatment area with a higher variation observed for smaller treatment areas. Postimplantation dose evaluation was feasible.

CONCLUSIONS

Commissioning and clinical deployment of CivaSheet was feasible using BrachyVision for postoperative dose evaluation. Experimental verification confirmed that the available TG-43 dosimetry parameters are accurate for clinical use.

High dose-rate Intra-Operative Radiation Therapy During High Risk Genitourinary Surgery: Initial Observations and a Proposal for its Study in Bladder Cancer

BACKGROUND

High dose-rate Intra-Operative Radiation Therapy (HD-IORT) is used to provide effective local control for patients with high-risk locally advanced or recurrent tumors. However, the utility of HD-IORT for patients with bladder cancer has not been studied.

OBJECTIVE

To characterize our institutional experience with HD-IORT in patients with cancer requiring genitourinary surgery, in an effort to identify patients with bladder cancer that may benefit from HD-IORT.

METHODS

We performed a retrospective review of all patients who have undergone HD-IORT during genitourinary surgery at our institution. Patients were stratified by surgical margin status, and primary outcomes assessed were overall survival, recurrence free survival and 90-day complications. Patients undergoing cystectomy and HD-IORT with sarcomatoid urothelial cancer were compared to a similar cohort undergoing cystectomy alone. A sample case of one such patient is discussed in detail.

RESULTS

84 patients at our institution have undergone HD-IORT with genitourinary surgery. Positive surgical margin status was the greatest predictor of both OS (HR = 3.42) and RFS (HR = 2.61). The overall 90-day complication rate was 61%, with wound infections (43%) and GI complications (21%) being most common. 4 of these patients had sarcomatoid urothelial histology, and all are still alive with >2 yrs follow up. This compares to a 52% 1 yr survival in our sarcomatoid urothelial cohort (25 pts) that did not undergo HD-IORT.

CONCLUSIONS

Our institutional experience with HD-IORT has been promising, particularly among patients with locally advanced disease and sarcomatoid histology. We are currently enrolling patients in a multi-institutional registry to assess the utility of HD-IORT in high risk bladder cancer.

Standard fractionation external beam radiotherapy with and without intraoperative radiotherapy for locally recurrent rectal cancer: the role of local therapy in patients with a high competing risk of death from distant disease

OBJECTIVE

We sought to evaluate the effectiveness and safety of utilizing radiotherapy (RT) with standard fractionation, with or without intraoperative RT (IORT), to treat locally recurrent rectal cancer (LRRC).

METHODS

Retrospective review of 25 patients with LRRC treated with standard fractionation RT from 2005 to 2011. 15 patients (60%) had prior pelvic RT and 10 (40%) had synchronous metastases. The median equivalent dose in 2-Gy fractions was 30 and 49.6 Gy in patients with and without prior RT, respectively. 23 patients (92%) received concurrent chemotherapy and 16 (64%) underwent surgical resection. Eight patients (33.3%, four with and four without prior RT) received IORT. A competing risks model was developed to estimate the cumulative incidence of local failure with death treated as a competing event.

RESULTS

Median follow-up was 36.9 months after the date of local recurrence. 3-year rates of overall survival (OS), local control (LC) and death with LC were 51.6%, 73.3% and 69.2%, respectively. On multivariable analysis, surgical resection was significantly predictive of improved OS (p < 0.05). If surgical resection were removed from the multivariable model, given the collinearity between IORT delivery and surgical resection, then IORT also became a significant predictor of OS (p < 0.05). Systemic disease at the time of local recurrence was not associated with either LC or OS. No patient had grade ≥3 acute or late toxicity.

CONCLUSION

RT with standard fractionation is safe and effective in the treatment of patients with LRRC, even in patients with significant risk of systemic disease and/or history of prior RT. Advances in knowledge: The utility of RT with standard fractionation, generally with chemotherapy, in the treatment of LRRC is demonstrated. In this high-risk cohort of patients with a 40% incidence of synchronous metastatic disease, surgical resection of the recurrence was the major predictor of OS, though a benefit to IORT was also suggested. No patients had grade ≥3 acute or late toxicity, though 40% had undergone prior RT, underscoring the tolerability of standard fractionation RT in this setting.

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.

Clinical outcome of interstitial pulsed dose rate brachytherapy in multimodality treatment of locally advanced primary or recurrent rectal and sigmoid cancer with high risk of incomplete microscopic resection

OBJECTIVE

To evaluate the role of interstitial pulsed dose rate brachytherapy (PDR-BT) in multimodality treatment of locally advanced primary or recurrent rectal and sigmoid cancer with high risk of microscopic incomplete resection (R1).

METHODS AND MATERIAL

A total of 73 consecutive patients (recurrent/primary: 40/33) were treated with PDR-BT between 2001 and 2010. Patients received preoperative external beam radiotherapy (EBRT) and concomitant chemotherapy. Following resection of the tumor and the involved pelvic organs, a median of four (3-8) catheters were sutured to the tumor bed with a distance of approximately 1 cm between the catheters. A target respecting the catheters with a margin of 5 mm was contoured on computed tomography (CT) and three-dimensional (3D) dose planning with a planning aim for BT of D90 > 30 Gy, (0.6 Gy/pulse, 1 pulse/h) was performed. Previously irradiated patients (27%) underwent surgery that was directly followed by PDR-BT. Postoperative EBRT was then applied to the tumor bed 3-5 weeks after PDR-BT.

RESULTS

A total of 23 patients (31%) received a radical resection (R0) and 45 patients (62%) received an R1 resection. Five patients (7%) received a macroscopic incomplete resection (R2). The five-year overall survival was 33%. Local control at five years was 67% for patients who received a R0 resection and 32% for patients who received an R1 resection. The five-year actuarial risk of a grade 3-4 BT-related complication was 5%.

CONCLUSIONS

Meaningful disease control and survival can be obtained at an acceptable rate of late morbidity in selected patients with locally advanced primary and recurrent rectal or sigmoid cancer using (chemo) RT, extensive surgery and PDR-BT when a high risk of an R1 resection is expected.

Long-Term Survival After High-Dose-Rate Brachytherapy for Locally Advanced or Recurrent Colorectal Adenocarcinoma

BACKGROUND

We evaluated outcomes of intraoperative radiotherapy delivered with focal high-dose-rate (HDR) brachytherapy [intraoperative radiotherapy (IORT)] in the management of locally recurrent (LR) and locally advanced (LA) primary T4 colorectal carcinoma (CRC). LR CRC or LA primary disease is a clinical challenge due to the difficulty in obtaining negative margins after radical surgery and the high risk of subsequent recurrence. Few data exist on long-term outcomes of patients treated with surgery and HDR-IORT for LR or LA primary CRC.

METHODS

Three hundred CRC patients underwent HDR-IORT to the pelvis with gross surgical resection during November 1992-December 2007. Median follow-up for surviving patients was 53 (range 5-216) months. Eighty-eight patients (29 %) were treated for LA primary and 212 (71 %) LR disease. HDR-IORT was delivered using an iridium-192 remote afterloader and a Harrison-Anderson-Mick applicator. Median IORT dose was 1,500 (range 1,000-2,000) cGy.

RESULTS

Five-year overall survival probability was 49 %. Positive margin status was associated with inferior overall survival and disease-free survival. Competing-risks analysis for time to local failure and distant metastases identified a 5-year cumulative incidence of local failure and distant metastases of 33 and 47 %, respectively. Five-year cumulative incidence of local failure was 22 % for the LA group and 38 % in the LR group. Five-year probability of disease-free survival was 48 and 31 % for LA and LR patients, respectively, and 5-year probability of overall survival was 56 and 45 % for LA and LR patients, respectively.

CONCLUSIONS

HDR-IORT combined with resection results in encouraging local control rates with acceptable toxicity for patients with locally aggressive CRC.

High-dose-rate intraoperative radiation therapy: the nuts and bolts of starting a program

High-dose-rate intraoperative radiation therapy (HDR-IORT) has historically provided effective local control (LC) for patients with unresectable and recurrent tumors. However, IORT is limited to only a few specialized institutions and it can be difficult to initiate an HDR-IORT program. Herein, we provide a brief overview on how to initiate and implement an HDR-IORT program for a selected group of patients with gastrointestinal and pelvic solid tumors using a multidisciplinary approach. Proper administration of HDR-IORT requires institutional support and a joint effort among physics staff, oncologists, surgeons, anesthesiologists, and nurses. In order to determine the true efficacy of IORT for various malignancies, collaboration among institutions with established IORT programs is needed.

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.

Present status and future directions of intraoperative radiotherapy

In this Review, we summarise recent published work on the use of intraoperative radiotherapy to treat common tumour sites in the primary or recurrent setting. Techniques, radiobiology, and the physics of intraoperative radiotherapy are also explored. Disease sites discussed in this Review include head and neck cancer, breast cancer, sarcoma, gastrointestinal cancer, genitourinary cancer, gynaecological cancer, thoracic cancer, and palliative applications.

Prospective single-arm study of intraoperative radiotherapy for locally advanced or recurrent rectal cancer

INTRODUCTION

This study aims to evaluate the feasibility and outcomes of intraoperative radiotherapy (IORT) using high-dose-rate (HDR) brachytherapy for locally advanced or recurrent rectal cancers. Despite preoperative chemoradiation, patients with locally advanced or recurrent rectal cancers undergoing surgery remain at high risk of local recurrence. Intensification of radiation with IORT may improve local control.

METHODS

This is a prospective non-randomised study. Eligible patients were those with T4 rectal cancer or pelvic recurrence, deemed suitable for radical surgery but at high risk of positive resection margins, without evidence of metastasis. Chemoradiation was followed by radical surgery. Ten gray (Gy) was delivered to tumour bed via an IORT applicator at time of surgery.

RESULTS

There were 15% primary and 85% recurrent cancers. The 71% received preoperative chemoradiation. R0, R1 and R2 resections were 70%, 22% and 7%, respectively. IORT was successfully delivered in 27 of 30 registered patients (90% (95% confidence interval (CI) = 73-98) ) at a median reported time of 12 weeks (interquartile range (IQR) = 10-16) after chemoradiation. Mean IORT procedure and delivery times were 63 minutes (range 22-105 minutes). Ten patients (37% (95% CI = 19-58) ) experienced grade 3 or 4 toxicities (three wound, four abscesses, three soft tissue, three bowel obstructions, three ureteric obstructions and two sensory neuropathies). Local recurrence-free, failure-free and overall survival rates at 2.5 years were 68% (95% CI = 52-89), 37% (95% CI = 23-61) and 82% (95% CI = 68-98), respectively.

CONCLUSION

The addition of IORT to radical surgery for T4 or recurrent rectal cancer is feasible. It can be delivered safely with low morbidity and good tumour outcomes.

Pelvic exenteration for rectal cancer: a systematic review

BACKGROUND

Pelvic exenteration is a potentially curative treatment for locally advanced primary or recurrent rectal cancer.

OBJECTIVE

This systematic review examines the current evidence regarding clinical and oncological outcomes in patients with locally advanced primary and recurrent rectal cancer who undergo pelvic exenteration.

DATA SOURCES

A literature search of PubMed, Medline, and the Cochrane library was undertaken, and studies published in the English language from January 2000 to August 2012 were identified.

STUDY SELECTION

Prospective and retrospective studies that report outcomes of pelvic exenteration for primary advanced and locally recurrent rectal cancer with or without subgroup evaluation were included for examination.

MAIN OUTCOME MEASURES

Oncological outcomes included 5-year survival, median survival, and local recurrence rates. Clinical outcomes included complication rates and perioperative mortality rates.

RESULTS

A total of 23 studies with 1049 patients were reviewed. The complication rates ranged from 37% to 100% (median, 57%) and the perioperative mortality rate ranged from 0% to 25% (median, 2.2%). The rate of local recurrence ranged from 4.8% to 61% (median, 22%). The median survival for primary advanced rectal cancers was 14 to 93 months (median, 35.5 months) and 8 to 38 months (median, 24 months) for locally recurrent rectal cancer.

LIMITATIONS

Our review was limited by the small sample sizes from single-institutional studies reporting outcomes over long periods of time with heterogeneity in both the disease and treatments reported.

CONCLUSIONS

Although the human costs and risks are significant, the potentially favorable survival outcomes make this acceptable in the absence of other effective treatment modalities that would otherwise result in debilitating symptoms that afflict patients who have advanced pelvic malignancy.

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 pelvic brachytherapy for treatment of locally advanced or recurrent colorectal cancer

BACKGROUND

The aim of this study was to evaluate the efficacy and morbidity of intraoperative radiation therapy (IORT) for advanced colorectal cancer.

METHODS

All patients undergoing IORT for locally advanced rectal cancer from 2001-2009 were reviewed for cancer recurrence, survival, and procedure-related morbidity. Cumulative event rates were estimated using the method of Kaplan and Meier.

RESULTS

Twenty-nine patients with locally advanced (n = 8) or recurrent (n = 21) rectal cancers were treated with IORT and resection. Surgical interventions included low anterior resection, abdominoperineal resection, pelvic exenteration, and a variety of non-anatomic resections of pelvic recurrences. R(0) resections were achieved in 16 patients, while R(1) resections were achieved in 10, and margins were grossly positive in 3 patients. IORT was delivered to all patients over a median area of 48 (42-72) cm(2) at a median dose of 12 (12-15) Gy. Local and overall recurrence rates were 24 % (locally advanced group) and 45 % (recurrent group). Median disease-free and overall survival were 25 and 40 months respectively at a median follow-up of 26 (18-42) months. The short-term (≤30 days) complication rate was 45 %. Eight patients developed local wound complications, 5 of which required operative intervention. Four patients developed intra-abdominal abscesses requiring drainage. Long-term (>30 days) complications were identified in 11 patients (38 %) and included long-term wound complications (n = 3), ureteral obstruction requiring stenting (n = 1), neurogenic bladder (n = 3), enteric fistulae (n = 2), small bowel obstruction (n = 1), and neuropathic pain (n = 1).

CONCLUSIONS

Intraoperative brachytherapy is a viable IORT option during pelvic surgery for locally advanced or recurrent colorectal cancer but is associated with high postoperative morbidity. Whether intraoperative brachytherapy can improve local recurrence rates for locally advanced or recurrent colorectal cancer will require further prospective investigation.

A 10-year experience of total pelvic exenteration for primary advanced and locally recurrent rectal cancer based on a prospective database

AIM

The study was conducted in a dedicated centre treating the majority of Danish patients with intended curative total pelvic exenteration for primary advanced (PARC) or locally recurrent (LRRC) rectal cancer. We compared PARC and LRRC and analysed postoperative morbidity and mortality, and long-term outcome.

METHOD

There were 90 consecutive patients (PARC/LRRC 50/40) treated between January 2001 and October 2010, recorded on a prospectively maintained database.

RESULTS

The median age was 63 (32-75) years with a gender ratio of 7 women to 83 men. All patients were American Society of Anesthesiologists level I or II. Sacral resection was performed in five patients with PARC and 15 with LRRC (P=0.002). R0 resection was achieved in 33 (66%) patients with PARC and in 15 (38%) with LRRC, R1 resection in 17 (34%) with PARC and 20 (50%) with LRRC and R2 resection in five (13%) with LRRC. R0 resection was more frequent in PARC (P=0.007). Forty-four (49%) patients had no postoperative complications. Fifty-five major complications were registered. Two (2.2%) patients died within 30 days, and the total in-hospital mortality was 5.6%. The median follow-up was 12 (0.4-91) months. The 5-year survival was 46% for PARC and 17% for LRRC (P=0.16).

CONCLUSION

Pelvic exenteration is associated with considerable morbidity but low mortality in an experienced centre. Pelvic exenteration can improve long-term survival, especially for patients with PARC. However, pelvic exenteration is also justified for patients with LRRC.

Surgery and high-dose-rate intraoperative radiation therapy for recurrent squamous-cell carcinoma of the anal canal

BACKGROUND

Locoregionally recurrent squamous-cell carcinoma of the anal canal is managed with salvage surgery. High-dose-rate intraoperative radiation therapy has been used in selected patients with this disease to reduce the risk of local recurrence.

OBJECTIVE

The aim of this article is to present our institutional experience with this technique.

DESIGN

Medical records of 14 patients with locoregionally recurrent squamous-cell carcinoma of the anal canal who underwent this technique between 1992 and 2007 were reviewed.

SETTING

The study was conducted at an academic cancer center.

PATIENTS

The median age was 45 years (range, 36-77), and 13 of the patients were women. All had prior radiation with or without chemotherapy.

INTERVENTIONS

The surgical procedures included abdominoperineal resection with or without sacrectomy (n = 8), low anterior resection (n = 2), and pelvic exenteration (n = 4). The median radiation dose was 1500 cGy (range, 1500-1750). All cases of radiographic invasion of adjacent structures correctly predicted pathologic invasion. There was pathologic invasion into adjacent structures in 11 cases (79%), and adherence to the sacrum without invasion in 2 cases (14%). Surgical margins were positive (n = 6), close (<1 mm) (n = 3), and negative (n = 5).

RESULTS

The median follow-up from our technique was 17 months (range, 5-145). Subsequent recurrence occurred in 11 cases, at a median of 8 months from treatment. Two-year actuarial control was 7.1%, and the overall survival was 21.4%. Acute toxicities included wound-healing complications (n = 6); gastrointestinal obstruction (n = 5); neurogenic bladder (n = 1); ureteral stricture (n = 3); and peripheral neuropathy (n = 2).

LIMITATIONS

This is a small retrospective series in which the meaningful analysis of associations between clinical variables and outcomes was not possible.

CONCLUSION

Salvage surgery with high-dose-rate intraoperative radiation therapy did not appear to be associated with a locoregional control or survival benefit in this series. The addition of high-dose-rate intraoperative radiation therapy to salvage surgery is insufficient to compensate for positive surgical margins. Preoperative imaging should be used to aid in patient selection to identify those patients in whom negative margins can be obtained and to aid in the determination of appropriate salvage surgery.

Adjuvant Radiation Therapy of Retroperitoneal Sarcoma: The Role of Intraoperative Radiotherapy (IORT)

Purpose. The purpose is to review the natural history, the clinicopathological prognostic factors, and the role of adjuvant radiation therapy with particular attention to the limited but favorable experience with IORT.Methods. Retroperitoneal sarcomas present a continuing therapeutic challenge to the oncologist. In contrast to sarcomas of the extremity and superficial trunk in which complete resection plus radiation therapy results in excellent local control, sarcomas of the retroperitoneum are difficult to resect and even if completely resected, demonstrate high rates of local relapse, the primary pattern of failure. Due to the proximity of normal organs, the delivery of therapeutic doses of adjuvant external beam radiation therapy is problematic.To deliver adequate doses (>60 Gy) of external beam to most patients would result in unacceptable toxicity. The therapeutic dilemma is unfortunate and better strategies are needed. One attractive approach has been to incorporate intraoperative radiation therapy (IORT) with maximal resection and external beam radiation. Results and Discussion. A number of institutions have explored this approach with encouraging preliminary results.

Management of recurrent rectal cancer

BACKGROUND

Here we present a concise review on the evaluation and management of locally recurrent rectal cancer, which despite marked reductions in the rate of recurrent rectal cancer remains an important problem.

METHODS

This educational review discusses the diagnosis, evaluation, and management of recurrent rectal cancer.

RESULTS

Despite improvements in both the neoadjuvant and surgical management of rectal cancer, local recurrence is still an important problem, with documented recurrence rates of 4% to 8%. The local management of recurrence requires a team of specialist. Accurate detection and diagnosis followed by chemoradiotherapy and surgical resection may result in 5-year survival rates of up to 35%.

CONCLUSIONS

We discuss the diagnosis, evaluation, and management of locally recurrent rectal cancer. Locally recurrent rectal cancer can be successfully managed with multimodal therapy leading to successful palliation and often cure.

Can unresectable colorectal cancer be cured?

A multimodality regimen that includes EBRT, chemotherapy, maximal surgical resection, and IORT, when used in patients with initially unresectable primary colon or rectal adenocarcinoma, is associated with excellent long-term local control, and a 5-year overall survival of 52%. Distant metastases account for most treatment failures, occurring in roughly 50%. Treatment-related morbidity is high, with a long-term complication rate that approaches 50%. These results suggest that selected patients with advanced unresectable disease benefit from an aggressive approach. Additional effort needs to focus on reducing the rate of systemic failure with more effective chemotherapy regimens and minimizing the frequency of long-term procedural complications.

Unresectable colorectal cancer can be cured with multimodality therapy

OBJECTIVE

The aim of this study was to determine in what manner aggressive external beam radiotherapy (EBRT), chemotherapy, surgical resection, and intraoperative radiotherapy (IORT) impact relapse and survival in patients with locally unresectable primary colorectal cancer.

SUMMARY BACKGROUND DATA

Patients with colorectal cancer fixed to critical structures (eg, IVC and pelvic sidewall) are considered locally "unresectable" for cure and treated with palliative therapy.

METHODS

One hundred forty-six patients (65% males) with locally unresectable colon (40) and rectal (106) cancer were treated with EBRT, chemotherapy, surgical resection, and IORT. Final surgical margins were close, but negative in 100 patients (68%), microscopically positive in 28 (19%), and grossly positive in 18 (13%). Kaplan-Meier method was used to visualize survival and relapse curves; groups were compared using the log-rank test.

RESULTS

Median overall survival was 3.7 years. Median overall survival (years) favored patients with age <58 (7.6 vs. 3.6; P = 0.0012), those receiving adjuvant chemotherapy (9.4 versus 3.9; P = 0.0019), and those with negative or microscopic margins (6.3 vs. 1.9; P = 0.0006). There were no perioperative deaths. Fifteen complications occurred in 12 patients (8%) within 30 days of surgery/IORT. One hundred nineteen long-term complications occurred in 77 patients (53%), most commonly peripheral neuropathy (19%), bowel obstruction (14%), and ureteral obstruction (12%).

CONCLUSIONS

Aggressive multimodality therapy for locally unresectable primary colorectal cancer results in excellent local disease control and a 5-year disease-free and overall survival rate of 43% and 52% respectively with no operative mortality and acceptable perioperative morbidities.

Evidence and research in rectal cancer

The main evidences of epidemiology, diagnostic imaging, pathology, surgery, radiotherapy, chemotherapy and follow-up are reviewed to optimize the routine treatment of rectal cancer according to a multidisciplinary approach. This paper reports on the knowledge shared between different specialists involved in the design and management of the multidisciplinary ESTRO Teaching Course on Rectal Cancer. The scenario of ongoing research is also addressed. In this time of changing treatments, it clearly appears that a common standard for large heterogeneous patient groups have to be substituted by more individualised therapies based on clinical-pathological features and very soon on molecular and genetic markers. Only trained multidisciplinary teams can face this new challenge and tailor the treatments according to the best scientific evidence for each patient.

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.

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

BACKGROUND

We analyzed the long-term results of patients with locally advanced rectal cancer using a multimodal approach consisting of total mesorectal excision (TME), intraoperative electron-beam radiation therapy (IOERT), and pre- or postoperative chemoradiation (CRT).

PATIENTS AND METHODS

Between 1991 and 2003, 210 patients with locally advanced rectal cancer (65 International Union Against Cancer [UICC] Stage II, 116 UICC Stage III, and 29 UICC Stage IV cancers) were treated with TME, IOERT, and preoperative or postoperative CHT. A total of 122 patients were treated postoperatively; 88 patients preoperatively. Preoperative or postoperative fluoropyrimidine-based CRT was applied in 93% of these patients.

RESULTS

Median age was 61 years (range, 26-81). Median follow-up was 61 months. The 5-year actuarial overall survival (OS), disease-free survival (DFS), local control rate (LC), and distant relapse free survival (DRS) of all patients was 69%, 66%, 93%, and 67%, respectively. Multivariate analysis revealed that UICC stage and resection status were the most important independent prognostic factors for OS, DFS, and DRS. The resection status was the only significant factor for local control. T-stage, tumor localization, type of resection, and type of chemotherapy had no significant impact on OS, DFS, DRS, and LC. Acute and late complications > or =Grade 3 were seen in 17% and 13% of patients, respectively.

CONCLUSION

Multimodality treatment with TME and IOERT boost in combination with moderate dose pre- or postoperative CRT is feasible and results in excellent long-term local control rates in patients with intermediate to high-risk locally advanced rectal cancer.

Three-dimensional conformal radiotherapy combined with FOLFOX4 chemotherapy for unresectable recurrent rectal cancer

AIM: To investigate the effect of three-dimensional conformal radiotherapy (3-DCRT) in combination with FOLFOX4 chemotherapy for unresectable recurrent rectal cancer.

METHODS: Forty-eight patients with unresectable recurrent rectal cancer were randomized and treated by 3-DCRT or 3-DCRT combined with FOLFOX4 chemotherapy between September 2001 and October 2003. For the patients without prior radiation history, the initial radiation was given to the whole pelvis by traditional methods with tumor dose of 40 Gy, followed by 3-DCRT for the recurrent lesions to the median total cumulative tumor dose of 60 Gy (range 56-66 Gy); for the post-radiation recurrent patients, 3-DCRT was directly given for the recurrent lesions to the median tumor dose of 40 Gy (36-46 Gy). For patients in the study group, two cycles chemotherapy with FOLFOX4 regimen were given concurrently with radiotherapy, with the first cycle given simultaneously with the initiation of radiation and the second cycle given in the fifth week for patients receiving conventional pelvis radiation or given in the last week of 3-DCRT for patients receiving 3-DCRT directly. Another 2-4 cycles (average 3.6 cycles) sequential FOLFOX4 regimen chemotherapy were given to the patients in the study group, beginning at 2-3 wk after chemoradiation. The outcomes of symptoms relieve, tumor response, survival and toxicity were recorded and compared between the study group and the control group.

RESULTS: For the study group and the control group, the pain-alleviation rates were 95.2% and 91.3% (P > 0.05); the overall response rates were 56.5% and 40.0% (P > 0.05); the 1-year and 2-year survival rates were 86.9%, 50.2% and 80.0%, 23.9%, with median survival time of 25 mo and 16 mo (P < 0.05); the 2-year distant metastasis rates were 39.1% and 56.0% (P = 0.054), respectively. The side effects, except peripheral neuropathy which was relatively severer in the study group, were similar in the the two groups and well tolerated.

CONCLUSION: Three-dimensional conformal radio-therapy combined with FOLFOX4 chemotherapy for unresectable recurrent rectal cancer is a feasible and effective therapeutic approach, and can reduce distant metastasis rate and improve the survival rate.

The optimization of dose delivery for intraoperative high-dose-rate radiation therapy using curved HAM applicators

BACKGROUND AND PURPOSE

To determine the effect of the curvature of Harrison-Anderson-Mick applicators on the dose distribution in high-dose-rate intraoperative radiation therapy (HDR-IORT).

MATERIAL AND METHODS

Treatment planning was performed with flat applicators using (192)Ir as the radioactive source, and dwell times were optimized using dose-point optimization techniques. These optimized dwell times were then used for the curved applicators, and the dose distributions that would actually be delivered to patients were determined.

RESULTS

The dose directly below the central catheter was strongly dependent on the curvature of the applicator. Steep parabolic curves caused underdoses of as much as 19% at a point 1cm from the convex side of the applicator. The rate of dose reduction with increasing distance from the applicator surface was also a function of the curvature of the applicator.

CONCLUSIONS

The curvature of the applicator profoundly affects dosimetry and can be exploited to optimize coverage of the target during HDR-IORT procedures. To ensure accurate dose delivery, these dose perturbations must be accounted for in the planning process. We recommend maintaining a dosimetry atlas of various applicator sizes and curvatures in addition to one for flat applicators.

Outcome after curative resection for locally recurrent rectal cancer

PURPOSE

Few biologic markers have been studied as prognostic factors in recurrent rectal carcinoma patients. We sought to determine the influence of clinical, pathologic, and biologic (p53, bcl-2, and ki-67) variables on survival after curative resection of locally recurrent rectal cancer.

METHODS

Retrospective review of patients with locally recurrent rectal cancer who received surgery with curative intent.

RESULTS

From 1988 to 1998, 134 patients with locally recurrent rectal cancer underwent operative exploration. Curative resection was performed in 85 patients. Median follow-up was 43 (range, 1.3-149) months. On multivariate analysis, negative predictors of overall survival included an elevated carcinoembryonic antigen level (P=0.02; hazard ratio 2.41; 95 percent confidence interval, 1.19-4.89) and an R1 resection margin (P = 0.01; hazard ratio, 2.81; 95 percent confidence interval, 1.27-6.21). In 26 patients for whom biologic variables were available, p53, bcl-2, and ki-67 did not significantly impact disease-specific survival or overall survival. Five-year disease-specific survival, overall survival, and pelvic control rates were 46, 36, and 51 percent respectively. Of the 50 patients who relapsed, time to second local recurrence was longer than time to development of metastasis (median, 16.5 vs. 9 months). Median survival for patients with metastatic recurrence was 26.l vs. 41.5 months for those with a subsequent local recurrence alone.

CONCLUSIONS

Approximately two-thirds of patients with locally recurrent rectal cancer can be resected for cure. Preoperative carcinoembryonic antigen and an R0 resection margin were the only significant predictors of overall survival. p53, bcl-2, and ki-67 did not impact survival outcomes.

Surgical resection and high dose rate intraoperative radiation therapy for locally recurrent rectal cancer

For intra-pelvic recurrence of rectal cancer, surgical resection is technically difficult and must be aggressive to achieve a high rate of negative resection margins. Resection with clear margins can be curative, particularly for those patients with true anastomotic recurrence. HDR-IORT is a safe, feasible, versatile, logistically sound modality that is highly reliable in delivering radiation to at-risk surgical margins in the pelvis. Despite surgery and IORT, overall local failure rates in this population are 33 to 50 percent. The most important prognostic variable is the state of surgical resection margins. At our institution, in patients with negative and positive resection margins the 2-year actuarial local recurrence rates are 33 percent versus 73 percent and 5-year survival rates are 51 percent versus 16 percent, respectively. On subset analysis, the most favorable outcome was seen in patients with true anastomotic recurrences (78 percent 5-year survival).

Adjuvant Radiation Therapy for Resectable Retroperitoneal Soft Tissue Sarcoma

BACKGROUND

In the management of retroperitoneal sarcomas it is necessary to achieve local control to ensure survival. The role of adjuvant radiation therapy (RT), either pre- or postoperative, remains controversial.

METHODS

Outcomes for 40 patients with retroperitoneal sarcoma treated with surgery and postoperative RT (n = 25) or preoperative RT (n = 15) were analyzed for variables prognostic for local control, survival, and associated complications.

RESULTS

Patterns of failure for patients treated by resection and postoperative RT were local (n = 4), local and distant (n = 3), and distant (n = 3). The failure patterns for preoperative RT cases were local (n = 2), local and distant (n = 2); and distant (n = 4). Median time to local recurrence in the postoperative and preoperative RT series were 1 year and 2.5 years respectively. The margin status was predictive for local control (P = 0.0065) and survival (P = 0.0012), regardless of treatment sequence. Absolute 5-year survival was 12% with positive margins versus 69% if negative. Histologic grade was indicative of the risk for distant metastasis (low grade 8% vs high grade 64%; P = 0.1373), and significantly predicted 5-year absolute survival (low grade 77% vs high grade 34%; P = 0.0267). Postoperative RT was associated with significant complications (infection, hemorrhage, and bowel obstruction--2 cases each).

CONCLUSION

Compared with the surgery-alone series, adjuvant RT appears to improve the probability of local control. Preoperative RT may be the preferred sequence potentially to improve tumor resectability and local-regional control with less risk of complications than with postoperative RT.

Quantifying IOHDR brachytherapy underdosage resulting from an incomplete scatter environment

PURPOSE

Most brachytherapy planning systems are based on a dose calculation algorithm that assumes an infinite scatter environment surrounding the target volume and applicator. Dosimetric errors from this assumption are negligible. However, in intraoperative high-dose-rate brachytherapy (IOHDR) where treatment catheters are typically laid either directly on a tumor bed or within applicators that may have little or no scatter material above them, the lack of scatter from one side of the applicator can result in underdosage during treatment. This study was carried out to investigate the magnitude of this underdosage.

METHODS

IOHDR treatment geometries were simulated using a solid water phantom beneath an applicator with varying amounts of bolus material on the top and sides of the applicator to account for missing tissue. Treatment plans were developed for 3 different treatment surface areas (4 x 4, 7 x 7, 12 x 12 cm(2)), each with prescription points located at 3 distances (0.5 cm, 1.0 cm, and 1.5 cm) from the source dwell positions. Ionization measurements were made with a liquid-filled ionization chamber linear array with a dedicated electrometer and data acquisition system.

RESULTS

Measurements showed that the magnitude of the underdosage varies from about 8% to 13% of the prescription dose as the prescription depth is increased from 0.5 cm to 1.5 cm. This treatment error was found to be independent of the irradiated area and strongly dependent on the prescription distance. Furthermore, for a given prescription depth, measurements in planes parallel to an applicator at distances up to 4.0 cm from the applicator plane showed that the dose delivery error is equal in magnitude throughout the target volume.

CONCLUSION

This study demonstrates the magnitude of underdosage in IOHDR treatments delivered in a geometry that may not result in a full scatter environment around the applicator. This implies that the target volume and, specifically, the prescription depth (tumor bed) may get a dose significantly less than prescribed. It might be clinically relevant to correct for this inaccuracy.

Current clinical results of the Tsukuba BNCT trial

Nine high grade gliomas (5 glioblastomas and 4 anaplastic astrocytomas) were treated with BSH-based intaoperative boron neutron capture therapy (IOBNCT). BSH (100 mg/kg body weight) was intravenously injected, followed by single fraction irradiation using the mixed thermal/epithermal beam of Japan Research Reactor 4. The blood boron level at the time of irradiation averaged 29.9 (18.8-39.5)microg/g. The peak thermal neutron flux as determined by post-irradiation measurements varied from 1.99 to 2.77x10(9) n cm(-2)s(-1). No serious BSH-related toxicity was observed in this series. The interim survival data in this study showed median survival times of 23.2 months for glioblastoma and 25.9 months for anaplastic astrocytoma, results which are consistent with the current conventional radiotherapy with/without boost radiation. Of the 4 residual tumors, 2 showed complete response (CR) and 2 showed partial response (PR) within 6 months following BNCT. No linear correlation was proved between the dose and the occurrence of early neurological events. The maximum boron dose of 11.7-12.2 Gy in the brain related to the occurrence of radiation necrosis. The clinical application of a mixed thermal/epithermal beam and JRR-4 facilities on BSH-based IOBNCT proved to be safe and effective in this series.

Developments in treatment of primary irresectable rectal cancer

Abstract The treatment options for primary irresectable rectal cancers are discussed. Assessment of tumour stage is the first step for an appropriate choice of treatment. Following a diagnosis of rectal cancer, a vast array of diagnostic procedures is available to determine its stage, and thereby its best treatment options. From the many (new) diagnostic options the merits and drawbacks are discussed. If a diagnosis of irresectability is made, further treatment options should include radiotherapy in most cases, some aspects of timing and application, i.e. intra-operative treatment are discussed. Chemotherapy options are manifold, the results are discussed and some new options are explored.