Frameless single-session robotic radiosurgery of liver metastases in colorectal cancer patients

Stereotactic radiotherapy for liver oligometastases: a pooled analysis following the estro/eortc consensus recommendations

A large pooled analysis of liver oligometastases, classified accordingly to the ESTRO/EORTC recommendations, treated by stereotactic radiotherapy (SBRT) and Radiosurgery (SRS) was carried out. The clinical and dosimetric data of patients who underwent SBRT/SRS for liver metastases were analysed in terms of efficacy and toxicity profile. In particular, the Local Control (LC), the Distant Metastases Free Survival (DMFS), the Disease-Free Survival (DFS), the Overall Survival (OS), and the Next Systemic Therapy Free Survival (NEST-FS) rates were analysed. 113 patients (M/F: 49/64), accounting for a total of 150 hepatic lesions (March 2006-February 2023) in two Italian radiotherapy Institutions were evaluated. Median age was 67 years old (36-92) and 48 (42.5%) patients had at least one comorbidity. The majority of the lesions were induced (30.7%) or repeated oligoprogressive (12.7%) metastases. 98 lesions were treated with more than one daily fraction (mainly 50 Gy in 5 fractions), while 52 were radiosurgery treatments (mainly 32 Gy). The treatment response at 3-4 months was evaluable in 147 lesions: complete response was 32.0%, partial response 17.0%, and stable disease 32.0%. Actuarial LC, DMFS, DFS, OS, and NEST-FS at 1 year were 75.8%, 37.7%, 34.9%, 78.7%, and 59.4% respectively; while actuarial LC, DMFS, DFS, OS, and NEST-FS at 2 years were 52.1%, 24.9%, 21.9%, 51.3%, and 36.8%, respectively. The achievement of complete response, synchronous oligometastases, and no treatment interruptions correlated with a more favorable outcomes. As per the toxicity profile, we registered only two acute and one late toxicity cases higher than grade 2. Stereotactic treatment for liver metastases seems to be a safe and promising option in terms of local control. The best results in term of outcomes have been obtained in patients with complete response, synchronous oligometastases, favorable histology, and no treatment interruptions.

Robotic Stereotactic Body Radiation Therapy for Oligometastatic Liver Metastases: A Systematic Review of the Literature and Evidence Quality Assessment

INTRODUCTION

The role of stereotactic body radiation therapy (SBRT) as a locally effective therapeutic approach for liver oligometastases from tumors of various origin is well established. We investigated the role of robotic SBRT (rSBRT) treatment on oligometastatic patients with liver lesions.

MATERIAL AND METHODS

This review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. The PubMed and Scopus databases were accessed by two independent investigators concerning robotic rSBRT for liver metastases, up to 3 October 2023.

RESULTS

In total, 15 studies, including 646 patients with 847 lesions that underwent rSBRT, were included in our systematic review. Complete response (CR) after rSBRT was achieved in 40.5% (95% CI, 36.66-44.46%), partial response (PR) in 19.01% (95% CI, 16.07-22.33%), whereas stable disease (SD) was recorded in 14.38% (95% CI, 11.8-17.41%) and progressive disease (PD) in 13.22% (95% CI, 10.74-16.17%) of patients. Progression-free survival (PFS) rates at 12 and 24 months were estimated at 61.49% (95% CI, 57.01-65.78%) and 32.55% (95% CI, 28.47-36.92%), respectively, while the overall survival (OS) rates at 12 and 24 months were estimated at 58.59% (95% CI, 53.67-63.33%) and 44.19% (95% CI, 39.38-49.12%), respectively. Grade 1 toxicity was reported in 13.81% (95% CI, 11.01-17.18%), Grade 2 toxicity in 5.57% (95% CI, 3.82-8.01%), and Grade 3 toxicity in 2.27% (955 CI, 1.22-4.07%) of included patients.

CONCLUSIONS

rSBRT represents a promising method achieving local control with minimal toxicity in a significant proportion of patients. Further studies are needed to evaluate the role of rSBRT in the management of metastatic liver lesions.

Comprehensive Treatment Uncertainty Analysis and PTV Margin Estimation for Fiducial Tracking in Robotic Liver Stereotactic Body Radiation Therapy

OBJECTIVE

This study aims to quantify the uncertainties of CyberKnife Synchrony fiducial tracking for liver stereotactic body radiation therapy (SBRT) cases, and evaluate the required planning target volume (PTV) margins.

METHODS

A total of 11 liver tumor patients with a total of 57 fractions, who underwent SBRT with synchronous fiducial tracking, were enrolled for the present study. The correlation/prediction model error, geometric error, and beam targeting error were quantified to determine the patient-level and fraction-level individual composite treatment uncertainties. The composite uncertainties and multiple margin recipes were compared for scenarios with and without rotation correction during treatment.

RESULTS

The correlation model error-related uncertainty was 4.3±1.8, 1.4±0.5 and 1.8±0.7 mm in the superior-inferior (SI), left-right, and anterior-posterior directions, respectively. These were the primary contributors among all uncertainty sources. The geometric error significantly increased for treatments without rotation correction. The fraction-level composite uncertainties had a long tail distribution. Furthermore, the generally used 5-mm isotropic margin covered all uncertainties in the left-right and anterior-posterior directions, and only 75% of uncertainties in the SI direction. In order to cover 90% of uncertainties in the SI direction, an 8-mm margin would be needed. For scenarios without rotation correction, additional safety margins should be added, especially in the superior-inferior and anterior-posterior directions.

CONCLUSION

The present study revealed that the correlation model error contributes to most of the uncertainties in the results. Most patients/fractions can be covered by a 5-mm margin. Patients with large treatment uncertainties might need a patient-specific margin.

Frameless Single Robotic Radiosurgery for Pulmonary Metastases in Colorectal Cancer Patients

Background

Surgical intervention and radiation therapy are common approaches for pulmonary metastasectomy. The role of minimally invasive techniques in pulmonary metastases remains unclear. Frameless single robotic radiosurgery [CyberKnife (CK); Accuray Incorporated, Sunnyvale, CA] of pulmonary metastases in colorectal cancer (CRC) patients offers high precision local radiation therapy.

Methods

We analyzed the efficacy and safety of CK treatment for lung metastases in CRC in 34 patients and a total of 45 lesions. The primary endpoint was local control (LC); secondary endpoints were progression-free survival (PFS), overall survival (OS), distant control (DC), and safety-relevant events.

Results

Of the treated lesions, 34/45 (77.8%) decreased in size or remained unchanged [complete response (CR), partial response (PR), stable disease (SD)]; 8/45 (17.8%) lesions increased in size [progressive disease (PD)] and 2/45 (4.4%) lesions were not evaluable. Local progression was shown in 2 lesions (4.4 %). The median PFS period was six months. In a median follow-up time of 19.4 months, medium OS was 19.9 months (range: 3-61 months). Distant recurrence was observed in 21/34 patients (61.8 %). Intrapulmonary progression occurred in six patients. In 4/45 cases, fiducial placement led to a pneumothorax; three out of four patients needed chest tube insertion. No radiation-associated side effects were reported in 57.8% of patients. In 10/45 cases (22.2%), patients suffered asymptomatic radiographic changes; 7/45 cases (15.6%) reported a late onset of radiation-associated side effects. Maximal radiation-associated side effects reached the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer (RTOG/EORTC) Grade 1.

Conclusion

CK treatment of pulmonary metastases is safe and well-tolerated. For metastatic colorectal cancer (mCRC) patients with pulmonary metastases and not eligible for surgery, CK radiation offers a valuable treatment option.

Hepatic metastasis from colorectal cancer

Colorectal cancer (CRC) is one of the most common cancers in the world. About two third of patients with CRC will develop distant recurrence at some point in time. Liver is the most common site where distant metastasis takes place. While the overall survival (OS) of patients with metastatic CRC was poor about 3 decades ago, there has been tremendous improvement in this area in the recent years. With the advent of effective systemic chemotherapy and biologic agents and better understanding of the biological behaviour of the tumour, aggressive treatment strategies such as metastatectomy of the liver metastases (or lung metastases) are now acceptable. More importantly, it has transformed the way how stage IV CRCs are being managed. From predominantly palliative as the primary aim, a comprehensive multidisciplinary approach is now the mainstay of treatment with very successful outcomes. Combination of systemic therapies with liver resection has been shown to be effective in providing promising survival benefits. In addition, other adjunctive modalities in targeting the liver metastases such as ablation, combining resection and ablation, transarterial chemoembolization, stereotactic body radiotherapy (SBRT), hepatic artery perfusion, etc. have also been demonstrated variable outcome in treating colorectal liver metastasis (CRLM). Very recently, transplant oncologists have also explored using liver transplantation as a treatment modality for unresectable CRLM, which has demonstrated very good long-term survival in well selected cases. The new paradigm in the treatment of metastatic CRC has dawned.

[Liver stereotactic body radiotherapy: Clinical features and technical consequences, results. Which treatment machine in which situation?]

Liver stereotactic body radiotherapy is a developing technique for the treatment of primary tumours and metastases. Its implementation is complex because of the particularities of the treated organ and the comorbidities of the patients. However, this technique is a treatment opportunity for patients otherwise in therapeutic impasse. The scientific evidence of liver stereotactic body radiotherapy has been considered by the French health authority as insufficient for its widespread use outside specialized and experienced centers, despite a growing and important number of retrospective and prospective studies, but few comparative data. This article focuses on the specific features of stereotactic body radiotherapy for liver treatments and the results of published studies of liver stereotactic body radiotherapy performed with classic linear accelerators and dedicated radiosurgery units.

[Technical aspects and indications of extracranial stereotactic radiotherapy]

Extracranial stereotactic radiotherapy has developed considerably in recent years and is now an important part of the therapeutic alternatives to be offered to patients with cancer. It offers opportunities that have progressively led physicians to reconsider the therapeutic strategy, for example in the case of local recurrence in irradiated territory or oligometastatic disease. The literature on the subject is rich but, yet, there is no real consensus on therapeutic indications. This is largely due to the lack of prospective, randomized studies that have evaluated this technique with sufficient recoil. We propose a review of the literature on the technical aspects and indications of extracranial stereotactic radiotherapy.

[Stereotactic body radiotherapy for liver tumors: State of the art]

Thanks to the improvement in radiotherapy physics, biology, computing and imaging, patients presenting with liver tumors can be efficiently treated by radiation. Radiotherapy has been included in liver tumors treatment guidelines at all disease stages. Liver stereotactic radiotherapy has to be preferred to standard fractionated radiotherapy whenever possible, as potentially more efficient because of higher biological equivalent dose. Liver stereotactic radiotherapy planning and delivery require extensive experience and optimal treatment quality at every step, thus limiting its availability to specialized centres. Multicentre studies are difficult to develop due to a large technical heterogeneity. Respiratory management, image guidance and immobilization are considerations as important as machine type. The use of multimodal planning imaging is compulsory to achieve expected contouring quality. Treatment efficacy is difficult to assess following liver stereotactic radiotherapy, but local control is high and toxicity unusual. As a consequence, liver stereotactic radiotherapy is part of multimodal and multidisciplinary management of liver tumors.

Dose to organ at risk and dose prescription in liver SBRT

Stereotactic body radiation therapy (SBRT) is delivered in a curative intent to many primary and secondary tumors. Concerning liver metastasis, SBRT can be safely delivered using one to five fractions. An excellent local control is obtained with doses from 20 to 60 Gy. For primary hepatic tumors, results are also good, but the risk of hepatic toxicity related to liver pre-existent pathology must be taken into account. Radiation induced liver disease (RILD) is not frequent in its classical presentation, but modifications of liver enzymes are often observed. Other toxicities of SBRT on the duodenum, small bowel and biliary tract are also described. With respect to contraindications and dose limitations on surrounding structures, SBRT is well tolerated and takes place among curative treatment of liver tumors, as surgery, radiofrequency and embolization.

SBRT planning for liver metastases: A focus on immobilization, motion management and planning imaging techniques

AIM

To evaluate the different techniques used for liver metastases Stereotactic Body Radiation Therapy (SBRT) planning. We especially focused on immobilization devices, motion management and imaging used for contouring.

BACKGROUND

Although some guidelines exist, there is no consensus regarding the minimal requirements for liver SBRT treatments.

MATERIALS AND METHODS

We reviewed the main liver metastases SBRT publications and guidelines; and compared the techniques used for immobilization, motion management, margins and imaging.

RESULTS

There is a wide variety of techniques used for immobilization, motion management and planning imaging.

CONCLUSIONS

We provide a subjective critical analysis of minimal requirements and ideal technique for liver SBRT planning.

Stereotactic Robotic Body Radiotherapy for Patients With Unresectable Hepatic Oligorecurrence

BACKGROUND

The purpose of this study was to analyze local control (LC), liver progression-free survival (PFS), and distant PFS (DFS), overall survival (OS), and toxicity in a cohort of patients treated with stereotactic body radiotherapy (SBRT) with fiducial tracking for oligorecurrent liver lesions; and to evaluate the potential influence of lesion size, systemic treatment, physical and biologically effective dose (BED), treatment calculation algorithms and other parameters on the obtained results.

PATIENTS AND METHODS

Unoperable patients with sufficient liver function had [18F]-fluorodeoxyglucose-positron emission tomography-computed tomography and liver magnetic resonance imaging to confirm the oligorecurrent nature of the disease and to further delineate the gross tumor volume (GTV). An intended dose of 45 Gy in 3 fractions was prescribed on the 80% isodose and adapted if risk-related. Treatment was executed with the CyberKnife system (Accuray Inc) platform using fiducials tracking. Initial plans were recalculated using the Monte Carlo algorithm. Patient and treatment data were processed using the Kaplan-Meier method and log rank test for survival analysis.

RESULTS

Between 2010 and 2015, 42 patients (55 lesions) were irradiated. The mean GTV and planning target volume (PTV) were 30.5 cc and 96.8 cc, respectively. Treatments were delivered 3 times per week in a median of 3 fractions to a PTV median dose of 54.6 Gy. The mean GTV and PTV D98% were 51.6 Gy and 51.2 Gy, respectively. Heterogeneity corrections did not influence dose parameters. After a median follow-up of 18.9 months, the 1- and 2-year LC/liver PFS/DFS/OS were 81.3%/55%/62.4%/86.9%, and 76.3%/42.3%/52%/78.3%, respectively. Performance status and histology had a significant effect on LC, whereas age (older than 65 years) marginally influenced liver PFS. Clinical target volume physical dose V45 Gy > 95%, generalized equivalent uniform dose (a = -30) > 45 Gy and a BED (α/β = 10) V105 Gy > 96% showed statistically significant effect on the LC. Acute Grade 3 gastrointestinal (GI) and late Grade 2 GI and fatigue toxicity were found in 5% and 11% patients, respectively.

CONCLUSION

Favorable survival and toxicity results support the potential paradigm shift in which the use of SBRT in oligorecurrent liver disease could benefit patients with unresectable or resectable liver metastases.

Institutional experience in the treatment of colorectal liver metastases with stereotactic body radiation therapy

AIM

To investigate whether the impact of dose escalation in our patient population represented an improvement in local control without increasing treatment related toxicity.

MATERIALS AND METHODS

A cohort of consecutive patients with colorectal liver metastases treated with stereotactic body radiation therapy (SBRT) between December 2002 and December 2013 were eligible for this study. Inclusion criteria were a Karnofsky performance status ≥80% and, according to the multidisciplinary tumor board, ineligibility for surgery or radiofrequency ablation. Exclusion criteria were a lesion size >6 cm, more than 3 metastases, and treatment delivered with other fractionation scheme than 3 times 12.5 Gy or 16.75 Gy prescribed at the 65-67% isodose. To analyze local control, CT or MRI scans were acquired during follow-up. Toxicity was scored using the Common Toxicity Criteria Adverse Events v4.0.

RESULTS

A total of 40 patients with 55 colorectal liver metastases were included in this study. We delivered 37.5 Gy to 32 lesions, and 50.25 Gy to 23 lesions. Median follow-up was 26 and 25 months for these two groups. Local control at 2 and 3 years was 74 and 66% in the low dose group while 90 and 81% was reached in the high dose group. No significant difference in local control between the two dose fractionation schemes could be found. Grade 3 toxicity was limited and was not increased in the high dose group.

CONCLUSIONS

SBRT for colorectal liver metastases offers a high chance of local control at long term. High irradiation doses may contribute to enhance this effect without increasing toxicity.

Stereotactic body radiation therapy for primary and metastatic liver tumors: From technological evolution to improved patient care

Technical developments allowed stereotactic body radiation therapy (SBRT) to deliver effective doses of irradiation with high precision in a small number of fractions. This paper reviews the role of SBRT for liver metastases, hepatocellular carcinoma and cholangiocarcinoma, paying special attention to patient eligibility and treatment outcomes regarding local control, toxicity and quality of life. As well as discussing specific issues of these different tumors, such as the presence of underlying liver cirrhosis and the impact on toxicity, it outlines the limitations of SBRT and future areas of development and research.

Prospective Longitudinal Assessment of Quality of Life for Liver Cancer Patients Treated With Stereotactic Body Radiation Therapy

PURPOSE

To evaluate quality of life (QoL), an important outcome owing to poor long-term survival, after stereotactic body radiation therapy (SBRT) to the liver.

METHODS AND MATERIALS

Patients (n=222) with hepatocellular carcinoma (HCC), liver metastases, or intrahepatic cholangiocarcinoma and Child-Pugh A liver function received 24-60 Gy of 6-fraction image-guided SBRT. Prospective QoL assessment was completed with the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core-30 (QLQ-C30) and/or Functional Assessment of Cancer Therapy-Hepatobiliary (FACT-Hep, version 4) questionnaires at baseline and 1, 3, 6, and 12 months after treatment. Ten HCC patients with Child-Pugh B liver function were also treated.

RESULTS

The QLQ-C30 was available for 205 patients, and 196 completed the FACT-Hep. No difference in baseline QoL (P = .17) or overall survival (P = .088) was seen between the HCC, liver metastases, and intrahepatic cholangiocarcinoma patients. Appetite loss and fatigue measured by the QLQ-C30 clinically and statistically worsened by 1 month after treatment but recovered by 3 months. At 3 and 12 months after treatment, respectively, the FACT-Hep score had improved relative to baseline in 13%/19%, worsened in 36%/27%, and remained stable in 51%/54%. Using the QLQ-C30 Global Health score, QoL improved in 16%/23%, worsened in 34%/39%, and remained stable in 50%/38% at 3 and 12 months, respectively. Median survival was 17.0 months (95% confidence interval [CI] 12.3-19.8 months). Higher baseline scores on both FACT-Hep and QLQ-C30 Global Health were associated with improved survival. Hazard ratios for death, per 10-unit decrease in QoL, were 0.90 (95% CI 0.83-0.98; P = .001) and 0.88 (95% CI 0.82-0.95; P = .001), respectively. Tumor size was inversely correlated with survival.

CONCLUSIONS

Liver SBRT temporarily worsens appetite and fatigue, but not overall QoL. Stereotactic body radiation therapy is well tolerated and warrants comparison against other liver-directed therapies.

Percutaneous radiofrequency ablation (RFA) or robotic radiosurgery (RRS) for salvage treatment of colorectal liver metastases

BACKGROUND

Stereotactic radiation therapy is an evolving modality to treat otherwise unresectable liver metastases. In this analysis, two local therapies: 1) single session robotic radiosurgery (RRS) and 2) percutaneous radiofrequency ablation (RFA) were compared in a total of 60 heavily pretreated colorectal cancer patients.

METHODS

Thirty patients with a total of 35 colorectal liver metastases not qualifying for surgery that were treated in curative intent with RRS were prospectively followed. To compare efficacy of both treatment modalities, patients treated with RFA during the same period of time were matched according to number and size of the treated lesions. Local tumor control, local disease free survival (DFS), and freedom from distant recurrence (FFDR) were analyzed for efficacy. Treatment-related side effects were recorded for comparison.

RESULTS

The median diameter of the treated lesions was 33 mm (7-53 mm). Baseline characteristics did not differ significantly between the groups. One- and two-year local control rates showed no significant difference but favored RRS (85% vs. 65% and 80% vs. 61%, respectively). A significantly longer local DFS of patients treated with RRS compared to RFA (34.4 months vs. 6.0 months; p < 0.001) was found. Both, median FFDR (11.4 months for RRS vs. 7.1 months for RFA p = 0.25) and the recurrence rate (67% for RRS and 63% for RFA, p > 0.99) were comparable.

CONCLUSION

Single session RRS is a safe and effective method to treat colorectal liver metastases. In this analysis, a trend towards longer DFS was seen in patients treated with RRS when compared to RFA.

Linac based radical radioablation of liver tumors

Due to the low percentage of resectable liver tumors, new alternative treatment modalities are used. Among them, radioablation, that is, by using a limited number of high dose radiation. The aim of this study was to evaluate the effectiveness of liver tumor radioablation at 36 Gy delivered in three fractions. The analyzed material comprised of 65 liver tumors. In 61 cases, we irradiated metastases (20 rectal cancers) and in 4 primary liver tumors. Radioablation, was done using 6 and 20 MV photons with a fraction dose of 12 Gy once a week up to a total dose of 36 Gy. During the follow-up we measured tumor diameters, and for our statistics we used a classical linear regression and the Bayesian approach. Mild and moderate late toxicity was observed. We found a significant absolute and relative decrease in tumor size during the first 6 months from the whole analyzed group. In subgroups with adenocarcinomas, metastases of gastrointestinal tract (GI) cancers, metastases of cancers other than GI cancers, and in the subgroup in which 2D-2D kV system (IGRT) and respiratory gating was used. The percentage of tumors with local control (lack of "in field" progression) after 6 months was 89%. The obtained results permit us to conclude that gated SBRT of liver tumors is an effective and safe treatment modality resulting in a significant regression of liver tumors and that the highest degree of tumor size reduction can be expected for metastases of non-gastro intestinal tract cancers.

Stereotactic body radiation therapy for patients with heavily pretreated liver metastases and liver tumors

We present our initial experience with CyberKnife stereotactic body radiation therapy (SBRT) in a heavily pretreated group of patients with liver metastases and primary liver tumors. From October 2007 to June 2009, 48 patients were treated at the Philadelphia CyberKnife Center for liver metastases or primary liver tumors. We report on 30 patients with 41 discrete lesions (1–4 tumors per patient) who received an ablative radiation dose (BED ≥ 79.2 Gy10 = 66 Gy EQD2). The treatment goal was to achieve a high SBRT dose to the liver tumor while sparing at least 700 cc of liver from radiation doses above 15 Gy. Twenty-three patients were treated with SBRT for metastatic cancer to the liver; the remainder (n = 7) were primary liver tumors. Eighty-seven percent of patients had prior systemic chemotherapy with a median 24 months from diagnosis to SBRT; 37% had prior liver directed therapy. Local control was assessed for 28 patients (39 tumors) with 4 months or more follow-up. At a median follow-up of 22 months (range, 10–40 months), 14/39 (36%) tumors had documented local failure. A decrease in local failure was found with higher doses of SBRT (p = 0.0237); 55% of tumors receiving a BED ≤ 100 Gy10 (10/18) had local failure compared with 19% receiving a BED > 100 Gy10 (4/21). The 2-year actuarial rate of local control for tumors treated with BED > 100 Gy10 was 75% compared to 38% for those patients treated with BED ≤ 100 Gy10 (p = 0.04). At last follow-up, 22/30 patients (73%) had distant progression of disease. Overall, seven patients remain alive with a median survival of 20 months from treatment and 57 months from diagnosis. To date, no patient experienced persistent or severe adverse effects. Despite the heavy pretreatment of these patients, SBRT was well tolerated with excellent local control rates when adequate doses (BED > 100 Gy10) were used. Median survival was limited secondary to development of further metastatic disease in the majority of patients.

Multidisciplinary approach of colorectal liver metastases

Colorectal cancer (CRC) is the second most common cause of cancer death in Spain. Fifty percent of patients will develop colorectal liver metastases (CLM) during the course of the disease. Less than 20% of patients with CLM are initially resectable and for them 5-year disease-free survival (DFS) is about 20-25%, with a high recurrence rate. CLM is a heterogeneous disease. From a clinical point of view, four main groups can be differentiated: initially resectable, not optimally resectable, unresectable that could be resectable and unresectable that never will be likely to be resected. Treatment of CLM must be established, always, in a multidisciplinary team discussion with an analysis of prognostic factors and resectability. For patients with resectable CLM, the EORTC trial 364 demonstrated that chemotherapy plus surgery is better than surgery alone. Consequently most patients should be treated with perioperative chemotherapy based on oxaliplatin, and if resection has been done without chemotherapy, they should receive adjuvant chemotherapy after R0 resection. Based on oncological factors, the 5-year survival rate after resection of CLM ranges from 60% to only 14% with a poor score. If a patient has more than one of the poor prognostic factors he should probably be referred for preoperative (induction) chemotherapy. Only a minority of patients with CLM are amenable to surgery; therefore, efforts have been made to increase the percentage of patients who could be candidates for resection. Studies, mostly retrospective, have confirmed the ability of neoadjuvant chemotherapy (conversion chemotherapy) to render some metastases resectable. The regimens we must use depend on the KRAS mutational status and the toxicity profiles of drugs in the context of each patient. In k-ras mutated tumours we can use bevacizumab combined with standard chemotherapy or concomitant administration of the three active agents (FOLFOXIRI) in suitable patients. In k-ras wild-type patients, the combination of cetuximab and FOLFIRI-FOLFOX improved response rates and resection rate in phase III-II trials. With a lower level of evidence, panitumumab is an alternative combined with FOLFOX. Bevacizumab is also an alternative as it does not depend on KRAS status. Radiotherapy is becoming an alternative in selected patients, where surgery is not an alternative. For the majority of patients, who will never be resectable, the continuum of care with chemotherapy will be the paradigm for their management.

Transarterial hepatic yttrium-90 radioembolization in patients with unresectable intrahepatic cholangiocarcinoma: factors associated with prolonged survival

INTRODUCTION

In unresectable intrahepatic cholangiocarcinoma (ICC), systemic chemotherapy often is viewed as the only option, although efficacy is limited. Radioembolization (RE) using yttrium-90 ((90)Y) microspheres is an accepted therapy for patients with hepatocellular-carcinoma or metastatic liver tumors. However, there are limited data on the value of RE in patients with ICC and few data on factors influencing prognosis. The purpose of our retrospective analysis was to establish which factors influenced time-to-progression (TTP) and overall survival (OS).

METHODS

Patients with unresectable ICC were treated with (90)Y resin-microspheres and assessed at 3-monthly intervals. Radiologic response was evaluated by using Response Criteria in Solid Tumors (RECIST). Baseline characteristics, biochemical/clinical toxicities, and response were examined for impact on TTP and OS.

RESULTS

Thirty-four treatments were administered to 33 patients without major complications. By RECIST, 12 patients had a partial response, 17 had stable disease, and 5 had progressive disease after 3 months. The median OS was 22 months posttreatment and 43.7 months postdiagnosis. Median TTP was 9.8 months. Survival and TTP were significantly prolonged in patients with ECOG 0 (vs. ECOG 1 or 2; median OS: 29.4, 10, and 5.1 months; TTP: 17.5, 6.9, and 2.4 months), tumor burden ≤25% (OS: 26.7 vs. 6 months; TTP: 17.5 vs. 2.3 months), or tumor response (PR or SD vs. PD; OS: 35.5, 17.7 vs. 5.7 months; TTP: 31.9, 9.8 vs. 2.5 months), respectively (P < 0.001).

CONCLUSIONS

Radioembolization is an effective and safe option for patients with unresectable ICC. Predictors for prolonged survival are performance status, tumor burden, and RECIST response.

The CyberKnife® Robotic Radiosurgery System in 2010

This review provides a complete technical description of the CyberKnife® VSI™ System, the latest addition to the CyberKnife product family, which was released in September 2009. This review updates the previous technical reviews of the original system version published in the late 1990s. Technical developments over the last decade have impacted virtually every aspect of the CyberKnife System. These developments have increased the geometric accuracy of the system and have enhanced the dosimetric accuracy and quality of treatment, with advanced inverse treatment planning algorithms, rapid Monte Carlo dose calculation, and post-processing tools that allow trade-offs between treatment efficiency and dosimetric quality to be explored. This review provides a system overview with detailed descriptions of key subsystems. A detailed review of studies of geometric accuracy is also included, reporting a wide range of experiments involving phantom tests and patient data. Finally, the relationship between technical developments and the greatly increased range of clinical applications they have allowed is reviewed briefly.