Phase II trial of high-dose conformal radiation therapy with concurrent hepatic artery floxuridine for unresectable intrahepatic malignancies

125I Radioactive Seeds Implantation Therapy for Hepatocellular Carcinoma

BACKGROUND

This study was to evaluate the outcome and the prognostic factors of unresectable hepatocellular carcinoma (HCC) patients with ¹²⁵I radioactive seeds implantation, who had failed transcatheter arterial chemoembolization (TACE).

METHODS

From September 2002 to March 2006, 48 patients with unresectable HCC underwent ¹²⁵I permanent implantation brachytherapy. Thirty-eight patients were male and 10 were female. Mean age was 59 years, ranginging from 32 to 86. Karnofsky performance status(KPS) was 100 in 10 patients, 80 in 21 patients, and 60 in 17 patients. According to Child-Pugh classification of liver, 34 patients were in class A and 14 patients in class B. Twenty-two patients had alpha-fetoprotein (AFP) level > 400 ng/ml. Tumor size was < 5cm in 17 patients, 5-10 cm in 18 patients, and > 10cm in 13 patients. Thirty-four patients had confluent tumors, 14 patients presented single hepatic tumor. Serum hepatitis antigen markers were positive for type B in 38 patients and type C in 10 patients. Twenty-two patients had Okuda Stage I, 24 patients Stage II, and 2 patients Stage III. According to the AJCC staging system (6th edition), 10 patients were in Stage II (T2N0M0), 20 in Stage IIIa (T3N0M0) and 18 in Stage IIIb (T4N0M0).

RESULTS

An objective response was observed in 34 of 48 patients, giving a response rate of 70.8%. The survival rates at 1, 2 and 3 years were75%, 45.8% and 27.1%, respectively. In the analysis of prognostic factors, tumor type, tumor size, Okuda stage, AJCC stage, Liver Child-Pugh, pretreatment AFP level, and matched peripheral dose (MPD) all had significant impact on survival.

CONCLUSIONS

The ¹²⁵I permanent implantation brachytherapy induced a substantial tumor response rate of 70.8% with survival rates at 1, 2 and 3 years of 75%, 45.8% and 27.1%, respectively, and a median survival time of 15.5 months in patients with unresectable HCC who had failed TACE. The complications are acceptable and can be managed with conservative treatment. Although we do not know whether there is a survival benefit through the use of this treatment, ¹²⁵I permanent implantation brachytherapy seems to be a practical method of salvage for this subset of patients. Further study is warranted to evaluate the survival of such patients with controlled trial.

Proton beam therapy for large hepatocellular carcinoma

PURPOSE

To investigate the safety and efficacy of proton beam therapy (PBT) in patients with large hepatocellular carcinoma (HCC).

METHODS AND MATERIALS

Twenty-two patients with HCC larger than 10 cm were treated with proton beam therapy at our institution between 1985 and 2006. Twenty-one of the 22 patients were not surgical candidates because of advanced HCC, intercurrent disease, or old age. Median tumor size was 11 cm (range, 10-14 cm), and median clinical target volume was 567 cm(3) (range, 335-1,398 cm(3)). Hepatocellular carcinoma was solitary in 18 patients and multifocal in 4 patients. Tumor types were nodular and diffuse in 18 and 4 patients, respectively. Portal vein tumor thrombosis was present in 11 patients. Median total dose delivered was 72.6 GyE in 22 fractions (range, 47.3-89.1 GyE in 10-35 fractions).

RESULTS

The median follow-up period was 13.4 months (range, 1.5-85 months). Tumor control rate at 2 years was 87%. One-year overall and progression-free survival rates were 64% and 62%, respectively. Two-year overall and progression-free survival rates were 36% and 24%, respectively. The predominant tumor progression pattern was new hepatic tumor development outside the irradiated field. No late treatment-related toxicity of Grade 3 or higher was observed.

CONCLUSIONS

The Bragg peak properties of PBT allow for improved conformality of the treatment field. As such, large tumor volumes can be irradiated to high doses without significant dose exposure to surrounding normal tissue. Proton beam therapy therefore represents a promising modality for the treatment of large-volume HCC. Our study shows that PBT is an effective and safe method for the treatment of patients with large HCC.

Extrapolation of normal tissue complication probability for different fractionations in liver irradiation

PURPOSE

The ability to predict normal tissue complication probability (NTCP) is essential for NTCP-based treatment planning. The purpose of this work is to estimate the Lyman NTCP model parameters for liver irradiation from published clinical data of different fractionation regimens. A new expression of normalized total dose (NTD) is proposed to convert NTCP data between different treatment schemes.

METHOD AND MATERIALS

The NTCP data of radiation- induced liver disease (RILD) from external beam radiation therapy for primary liver cancer patients were selected for analysis. The data were collected from 4 institutions for tumor sizes in the range of of 8-10 cm. The dose per fraction ranged from 1.5 Gy to 6 Gy. A modified linear-quadratic model with two components corresponding to radiosensitive and radioresistant cells in the normal liver tissue was proposed to understand the new NTD formalism.

RESULTS

There are five parameters in the model: TD(50), m, n, alpha/beta and f. With two parameters n and alpha/beta fixed to be 1.0 and 2.0 Gy, respectively, the extracted parameters from the fitting are TD(50)(1) = 40.3 +/- 8.4Gy, m =0.36 +/- 0.09, f = 0.156 +/- 0.074 Gy and TD(50)(1) = 23.9 +/- 5.3Gy, m = 0.41 +/- 0.15, f = 0.0 +/- 0.04 Gy for patients with liver cirrhosis scores of Child-Pugh A and Child-Pugh B, respectively. The fitting results showed that the liver cirrhosis score significantly affects fractional dose dependence of NTD.

CONCLUSION

The Lyman parameters generated presently and the new form of NTD may be used to predict NTCP for treatment planning of innovative liver irradiation with different fractionations, such as hypofractioned stereotactic body radiation therapy.

Phase I study of individualized stereotactic body radiotherapy of liver metastases

PURPOSE

To report on the outcomes of a phase I study of stereotactic body radiotherapy (SBRT) for treatment of liver metastases.

PATIENTS AND METHODS

Patients with liver metastases that were inoperable or medically unsuitable for resection, and who were not candidates for standard therapies, were eligible for this phase I study of individualized SBRT. Individualized radiation doses were chosen to maintain the same nominal risk of radiation-induced liver disease (RILD) for three estimated risk levels (5%, 10%, and 20%). Additional patients were treated at the maximal study dose (MSD) in an expanded cohort. Median SBRT dose was 41.8 Gy (range, 27.7 to 60 Gy) in six fractions over 2 weeks.

RESULTS

Sixty-eight patients with inoperable colorectal (n = 40), breast (n = 12), or other (n = 16) liver metastases were treated. Median tumor volume was 75.2 mL (range, 1.19 to 3,090 mL). The highest RILD risk level investigated was safe, with no dose-limiting toxicity. Two grade 3 liver enzyme changes occurred, but no RILD or other grade 3 to 5 liver toxicity was seen, for a low estimated risk of serious liver toxicity (95% CI, 0 to 5.3%). Six (9%) acute grade 3 toxicities (two gastritis, two nausea, lethargy, and thrombocytopenia) and one (1%) grade 4 toxicity (thrombocytopenia) were seen. The 1-year local control rate was 71% (95 CI, 58% to 85%). The median overall survival was 17.6 months (95% CI, 10.4 to 38.1 months).

CONCLUSION

Individualized six-fraction liver metastases SBRT is safe, with sustained local control observed in the majority of patients.

Innovative therapy for hepatocellular carcinoma: three-dimensional high-dose photon radiotherapy

The development of three-dimensional conformal radiotherapy (3DCRT) has enabled high dose radiation to be directed to tumour with a frank sparing of the non-tumour surrounding liver parenchyma without restriction due to tumour topography and size, presence of peritumourous satellite nodules or associated segmental portal vein thrombosis. 3DCRT can be safely delivered alone or concomitantly with transarterial chemoembolization (TACE), giving very encouraging results. Efficacy is strongly related to a smaller tumor size and higher dose of radiation while toxicity closely correlates to the pre-radiotherapy liver functions and the dose delivered to the uninvolved liver. These data has led to integrate 3DCRT in the multimodal treatment of HCC as a possible curative-intent option as well as surgical resection or percutaneous procedures although phase-III controlled studies are warranted to clarify this point. This may represent a promising approach in patients who are inoperable or for whom other ablation therapies are not feasible. The next steps will be the optimization of delivery modes of this type of photon therapy, taking account that other radiation modalities such as proton beam therapy for instance might be shown as of great interest within the next few years.

Options for radiotherapy in the treatment of liver metastases

Technologic advances have provided the means to deliver tumoricidal doses of radiation therapy (RT) to patients with unresectable colorectal liver metastases, while avoiding critical normal tissues, providing the opportunity to use RT for curative intent treatment of metastatic disease. For the current report, the expanded role of RT, with its different techniques in the setting of metastatic colorectal cancer, from palliation to cure was reviewed.

Treatment planning study to determine potential benefit of intensity-modulated radiotherapy versus conformal radiotherapy for unresectable hepatic malignancies

PURPOSE

To compare intensity-modulated radiotherapy (IMRT) with conformal RT (CRT) for hypofractionated isotoxicity liver RT and explore dose escalation using IMRT for the same/improved nominal risk of liver toxicity in a treatment planning study.

METHODS AND MATERIALS

A total of 26 CRT plans were evaluated. Prescription doses (24-54 Gy within six fractions) were individualized on the basis of the effective liver volume irradiated maintaining < or =5% risk of radiation-induced liver disease. The dose constraints included bowel (0.5 cm(3)) and stomach (0.5 cm(3)) to < or =30 Gy, spinal cord to < or =25 Gy, and planning target volume (PTV) to < or =140% of the prescribed dose. Two groups were evaluated: (1) PTV overlapping or directly adjacent to serial functioning normal tissues (n = 14), and (2) the liver as the dose-limiting normal tissue (n = 12). IMRT plans using direct machine parameter optimization maintained the CRT plan beam arrangements, an estimated radiation-induced liver disease risk of 5%, and underwent dose escalation, if all normal tissue constraints were maintained.

RESULTS

IMRT improved PTV coverage in 19 of 26 plans (73%). Dose escalation was feasible in 9 cases by an average of 3.8 Gy (range, 0.6-13.2) in six fractions. Three of seven plans without improved PTV coverage had small gross tumor volumes (< or =105 cm(3)) already receiving 54 Gy, the maximal prescription dose allowed. In the remaining cases, the PTV range was 9.6-689 cm(3); two had overlapped organs at risk; and one had four targets. IMRT did not improve these plans owing to poor target coverage (n = 2) and nonliver (n = 2) dose limits.

CONCLUSION

Direct machine parameter optimization IMRT improved PTV coverage while maintaining normal tissue tolerances in most CRT liver plans. Dose escalation was possible in a minority of patients.

Dosimetry of 125I radioactive seed implantation in therapy for hepatocellular carcinoma

Radioactive seed implantation, especially ¹²⁵I seeds implantation, which has provided an effective method for treatment of hepatocellular carcimoma (HCC), is attracting more and more attention all over the world, but its dosimetry need standardizing. Therefore, it is necessary to perform the prospective study on the dosimetry of ¹²⁵I radioactive seed implantation and seek for the best dosage and seed activity in order to enhance the therapeutic efficacy of ¹²⁵I seeds implantation in HCC treatment and protect the normal tissues surrounding the tumors.

Pilot clinical trial of localized concurrent chemoradiation therapy for locally advanced hepatocellular carcinoma with portal vein thrombosis

BACKGROUND

Patients with advanced hepatocellular carcinoma (HCC) with portal vein thrombosis (PVT) have a particularly grave prognosis. In the current study, an attempt was made to localize chemoradiation therapy (CCRT) followed by hepatic arterial infusion chemotherapy (HAIC) in patients with locally advanced HCC with PVT and good reserve liver function. The objective of the current study was to evaluate the therapeutic effect of localized CCRT followed by HAIC as a new treatment modality for these patients.

METHODS

Between January 1998 and December 2003, 40 patients were recruited. Concurrent regional chemotherapy using an intra-arterial implanted port plus localized external beam radiotherapy was performed with a total of 45 gray (Gy) over 5 weeks with conventional fractionation and hepatic arterial infusion of 5-fluorouracil (5-FU), which was administered during the first and fifth weeks of radiotherapy. One month after localized CCRT, HAIC with 5-FU and cisplatin was administered every 4 weeks.

RESULTS

One month after localized CCRT, an objective response was observed on the intention-to-treat analysis in 18 of 40 patients (45%). The actuarial 3-year overall survival rate was 24.1% and the median survival time was 13.1 months from the start of radiation treatment. Responders after localized CCRT demonstrated significantly better survival (P = .033) than nonresponders.

CONCLUSIONS

The substantial response rate as well as median survival time noted in the current study encourages the use of this new approach in patients with locally advanced HCC with PVT.

Hepatocellular carcinoma: radiation therapy

Although whole liver tolerance to radiation therapy (RT) is low, hepatocellular carcinoma (HCC) can be treated with focal high-dose RT, using a variety of advanced and specialized treatment strategies. Technical advancements in external beam RT that facilitate the safe delivery of RT to a wide spectrum of patients include conformal RT planning, breathing motion management, and image-guided RT. A variety of doses and RT fractionation schemes have been used safely alone or in combination with other therapies such as transarterial chemoembolization. Charged particles, produced from very specialized treatment units, are associated with particularly desirable dose distributions allowing tumoricidal doses to be delivered with sustained tumor control and little toxicity, even in the presence of Child-Pugh class B or C cirrhosis. Another strategy to deliver RT to HCC is hepatic arterial delivery of radioisotopes, such as microspheres tagged with yttrium-90. Liver toxicity is more likely in patients with reduced liver reserve and/or tumors infiltrating the majority of the liver. Phase II studies and a small phase III trial have demonstrated activity of hepatic arterial radioisotopes in HCC, providing rationale for large confirmatory randomized trials. Recurrences after RT occur most often within the liver, outside the high-dose irradiated volume, and outcomes after RT to very large and/or diffuse HCC are poor, providing rationale for combining RT with other therapies or novel radiation sensitizers. Given the vascular properties of HCC, there is rationale for investigating RT with anti-vascular endothelial growth factor-targeted agents.

Trends in local therapy for hepatocellular carcinoma and survival outcomes in the US population

BACKGROUND

Hepatocellular cancer (HCC) frequently presents with limitations to resection. We investigated survival outcomes after various local HCC therapies in US patients.

DATA SOURCES

Relationships between local HCC therapy modality and overall survival (OS) were analyzed from the Surveillance, Epidemiology and End Results (SEER) 1973-2003 database. Of 46,065 patients with primary hepatobiliary malignancy, 5,317 individuals with HCC had sufficient surgical data. The median age was 65 (range 0-105), and 73% of patients were male. The median tumor size was 6 cm (.2-30). There were single lesions (52%), multiple lesions (28%), and extrahepatic disease (20%). Mortality at 30 days was 8.4% (resection), 3.3% (transplantation), 3.2% (ablation), or 31% (no local therapy, P <.0001). Actuarial 5-year survival was 67% after transplantation, 35% after resection, 20% after ablation, and 3% for no or incomplete local therapy (P <.0001). Multivariate prognosticators were surgical modality, disease extent, grade (all at P <.0001), tumor size (P = .01), vascular invasion (P = .02), and age (P = .045). Compared to resection, risk ratios were .56 (transplantation) and 1.53 (ablation).

CONCLUSIONS

Long-term HCC survival can be observed after all 3 treatment approaches but is best after transplantation and resection, although likely biased through confounding patient selection variables. Preferred HCC treatment should be individualized based on morbidity and long-term OS prospects.

Estimate of radiobiologic parameters from clinical data for biologically based treatment planning for liver irradiation

PURPOSE

The Radiation Therapy Oncology Group (RTOG) is initiating a few new hypofractionation regimens (RTOG 0438) to treat liver cancer patients. To evaluate the radiobiologic equivalence between different regimens requires reliable radiobiologic parameters. The purpose of this work is to estimate a plausible set of such parameters for liver tumors and to design new optimized dose fractionation schemes to increase patient survival.

METHODS AND MATERIALS

A model was developed to fit clinical survival data from irradiation of a series of primary liver patients. The model consists of six parameters including radiosensitivity parameters alpha and alpha/beta, potential doubling time T(d). Using this model together with the Lyman model for calculations of the normal tissue complication probability, we designed a series of hypofractionated treatment strategies for liver irradiation.

RESULTS

The radiobiologic parameters for liver tumors were estimated to be: alpha/beta = 15.0 +/- 2.0 Gy, alpha = 0.010 +/- 0.001 Gy (-1), T(d) = 128 +/- 12 day. By calculating the biologically effective dose using the obtained parameters, it is found that for liver patients with an effective liver volume of approximately 45% the dose fractionation regimens suggested in RTOG 0438 can be escalated to higher dose for improved patient survival ( approximately 80% at 1 year) while keeping the normal tissue complication probability to less than 10%.

CONCLUSIONS

A plausible set of radiobiologic parameters has been obtained based on clinical data. These parameters may be used for radiation treatment planning of liver tumors, in particular, for the design of new treatment regimens aimed at dose escalation.

Conformal radiotherapy for hepatocellular carcinoma

Technical advancements in radiation therapy (RT) have facilitated the safe delivery of conformal, dose-escalated radiation to a wide spectrum of hepatocellular carcinoma (HCC) patients. A variety of doses and RT fractionation schemes have been used, and RT has been used in combination with transarterial chemoembolization (TACE). Compared to untreated historical controls or those treated with TACE alone, outcomes following RT alone or TACE and RT are better. Despite advances in RT delivery, liver toxicity following RT remains a dose-limiting factor, and investigations to better understand the pathophysiology of RT-induced liver toxicity are warranted. For most tumors, RT can provide sustained local control. However, HCC tends to recur within the liver away from the irradiated volume, providing rationale for combining RT with systemic or regional therapies. There is a particular interest in combining RT with anti-VEGF-targeted agents for their independent activity in HCC as well as their radiation sensitization properties. Randomized trials of RT are warranted.

The evolving role of radiation therapy in hepatocellular carcinoma

Technical advancements in imaging, in radiation therapy (RT) planning and RT delivery, have facilitated the safe delivery of conformal radiation therapy to patients with unresectable hepatocellular carcinoma (HCC). Although experience in liver cancer RT is limited, the RT technologies and tools to deliver RT safely are being disseminated rapidly. A variety of doses and RT fractionations have been used to treat HCC, and RT has been used in combination with other therapies including transarterial hepatic chemoembolization (TACE). Outcomes following RT alone or RT and TACE appear better than outcomes following similar historical controls of TACE alone, however, randomized trials of RT are needed. The first site of recurrence following RT is most often within the liver, away from the high dose volume, providing rationale for combining RT with regional or systemic therapies. Given the vascular properties of HCC, the combination of RT with anti-VEGF targeted agents may improve outcomes further.

Arterial chemotherapy and conformal radiation abolish malignant biliary obstruction

Malignant biliary obstruction has been a challenge to clinical practitioners, especially when it is serious and complete. Chemotherapy or radiation alone is often unsuccessful. In this study, the authors report a 59-year-old patient with complete common bile duct obstruction caused by cholangiocarcinoma who was treated with arterial chemotherapy followed by 3-dimensional conformal radiation, which resulted in a good clinical outcome.

Proton beam therapy for hepatocellular carcinoma adjacent to the porta hepatis

PURPOSE

To evaluate the efficacy and safety of proton beam therapy (PBT) for patients with hepatocellular carcinoma (HCC) located adjacent to the porta hepatis.

METHODS AND MATERIALS

Subjects of the study were 53 patients with HCC located within 2 cm of the main portal vein. All patients had tumor confined to the radiation field with no evidence of metastatic disease. All patients had hepatic function levels of a Child-Pugh score of 10 or less, Eastern Cooperative Oncology Group performance status of 2 or less, and no uncontrolled ascites. Patients underwent PBT of 72.6 GyE in 22 fractions from Sept 2001 to Dec 2004.

RESULTS

After 3 years, the actuarial survival rate was 45.1% and local control rate was 86.0%. Prognostic factors for survival included Child-Pugh score, number of tumors, and alpha-fetoprotein levels. No late treatment-related toxicity of Grade 2 or higher was observed.

CONCLUSIONS

The PBT delivering 72.6 GyE in 22 fractions appears to be effective and safe for HCC adjacent to the porta hepatis.

Early detection of liver cancer: diagnosis and management

Hepatocellular carcinoma (HCC) is the fifth most common cause of cancer deaths worldwide, and the incidence is rising. Despite a wide array of treatment options, fewer than half of candidates for potentially curative treatments receive them. The diagnosis and management of HCC require a multidisciplinary approach involving various clinical specialties. The foundation of diagnosis is high-quality imaging, with MRI being the test of choice. Some patients also require guided biopsy when MRI is equivocal. Treatment options depend upon the tumor stage and the degree of underlying synthetic dysfunction. Potentially curative treatments include surgical resection and transplantation. Other treatments that prolong survival include percutaneous ablation and transarterial chemoembolization. A new oral agent, sorafenib, was recently shown to prolong survival in patients with advanced HCC. By increasing surveillance and treatment of HCC, outcomes for these patients may be improved.

Phase I study of individualized stereotactic body radiotherapy for hepatocellular carcinoma and intrahepatic cholangiocarcinoma

PURPOSE

To report outcomes of a phase I study of individualized stereotactic body radiotherapy treatment (SBRT) for unresectable hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (IHC).

PATIENTS AND METHODS

Patients with unresectable HCC or IHC, and who are not suitable for standard therapies, were eligible for six-fraction SBRT during 2 weeks. Radiation dose was dependent on the volume of liver irradiated and the estimated risk of liver toxicity based on a normal tissue complication model. Toxicity risk was escalated from 5% to 10% and 20%, within three liver volume-irradiated strata, provided at least three patients were without toxicity at 3 months after SBRT.

RESULTS

Forty-one patients with unresectable Child-Pugh A HCC (n = 31) or IHC (n = 10) completed six-fraction SBRT. Five patients (12%) had grade 3 liver enzymes at baseline. The median tumor size was 173 mL (9 to 1,913 mL). The median dose was 36.0 Gy (24.0 to 54.0 Gy). No radiation-induced liver disease or treatment-related grade 4/5 toxicity was seen within 3 months after SBRT. Grade 3 liver enzymes were seen in five patients (12%). Two patients (5%) with IHC developed transient biliary obstruction after the first few fractions. Seven patients (five HCC, two IHC) had decline in liver function from Child-Pugh class A to B within 3 months after SBRT. Median survival of HCC and IHC patients was 11.7 months (95% CI, 9.2 to 21.6 months) and 15.0 months (95% CI, 6.5 to 29.0 months), respectively.

CONCLUSION

Individualized six-fraction SBRT is a safe treatment for unresectable HCC and IHC.

Treatment of unresectable cholangiocarcinoma with gemcitabine-based transcatheter arterial chemoembolization (TACE): a single-institution experience

BACKGROUND

Survival for patients with unresectable cholangiocarcinoma is reported to range from only 5-8 months without treatment. Systemic chemotherapy has not been shown to significantly improve survival, but newer regimens involving gemcitabine have shown increased response rates. Transcatheter arterial chemoembolization (TACE) has been shown to prolong survival in hepatocellular carcinoma patients, but experience using TACE in the treatment of cholangiocarcinoma is limited. We report our experience treating cholangiocarcinoma with TACE using chemotherapeutic regimens based on the well-tolerated drug gemcitabine.

METHODS

Forty-two patients with unresectable cholangiocarcinoma were treated with one or more cycles of gemcitabine-based TACE at our institution. Chemotherapy regimens used for TACE included: gemcitabine only (n=18), gemcitabine followed by cisplatin (n=2), gemcitabine followed by oxaliplatin (n=4), gemcitabine and cisplatin in combination (n=14), and gemcitabine and cisplatin followed by oxaliplatin (n=4).

RESULTS

Patients were 59 years of age (range 36-86) and received a median of 3.5 TACE treatments (range 1-16). Thirty-seven patients (88%) had central cholangiocarcinoma, and five (12%) had peripheral tumors. Nineteen patients (45%) had extrahepatic disease. Grade 3 adverse events (AEs) after TACE treatments were seen in five patients, whereas grade 4 AEs occurred in two patients. No patients died within 30 days of TACE. Median survival from time of first treatment was 9.1 months overall. Results did not vary by patient age, sex, size of largest initial tumor, or by the presence of extra-hepatic disease. Treatment with gemcitabine-cisplatin combination TACE resulted in significantly longer survival (13.8 months) compared to TACE with gemcitabine alone (6.3 months).

CONCLUSIONS

Our report represents the largest series to date regarding hepatic-artery-directed therapy for unresectable cholangiocarcinoma and provides evidence in favor of TACE as a promising treatment modality in unresectable cholangiocarcinoma. Our results suggest that gemcitabine-based TACE is well tolerated and confers better survival when given in combination therapy (with cisplatin or oxaliplatin) for patients with unresectable cholangiocarcinoma.

Liver function after irradiation based on computed tomographic portal vein perfusion imaging

PURPOSE

To determine whether individual and regional liver sensitivity to radiation could be assessed by measuring liver perfusion during a course of treatment using dynamic contrast-enhanced computed tomography scanning.

METHODS AND MATERIALS

Patients with intrahepatic cancer undergoing conformal radiotherapy underwent dynamic contrast-enhanced computed tomography (to measure perfusion distribution) and an indocyanine extraction study (to measure liver function) before, during, and 1 month after treatment. We hoped to determine whether the residual functioning liver (i.e., those regions showing portal vein perfusion) could be used to predict overall liver function after irradiation.

RESULTS

Radiation doses from 45 to 84 Gy resulted in undetectable regional portal vein perfusion 1 month after treatment. The volume of each liver with undetectable portal vein perfusion ranged from 0 to 39% and depended both on the patient's sensitivity and on dose distribution. There was a significant correlation between indocyanine green clearance and the mean of the estimated portal vein perfusion in the functional liver parenchyma (p < 0.001).

CONCLUSION

This study reveals substantial individual variability in the sensitivity of the liver to irradiation. In addition, these findings suggest that hepatic perfusion imaging may be a marker for liver function and has the potential to be a tool for individualizing therapy.

Conformal radiation therapy for portal vein tumor thrombosis of hepatocellular carcinoma

BACKGROUND AND PURPOSE

The prognosis of patients with portal vein tumor thrombosis (PVTT) from hepatocellular carcinoma (HCC) is poor; without treatment, their survival is less than 3months. We retrospectively evaluated the treatment outcomes of conformal radiation therapy (CRT) in patients with HCC-PVTT.

MATERIALS AND METHODS

Thirty-eight HCC patients with PVTT in whom other treatment modalities were not indicated underwent CRT. The total dose was translated into a biologic effective dose (BED) of 23.4-59.5Gy(10) (median 50.7Gy(10)) as the alpha/beta ratio=10. Predictive factors including the age, performance status, Child-Pugh classification, PVTT size, and BED were evaluated for tumor response and survival.

RESULTS

Complete response (CR), partial response (PR), stable disease (SD), and progressive disease (PD) were observed in 6 (15.8%), 11 (28.9%), 17 (44.7%), and 4 (10.5%) patients, respectively. The response rate (CR+PR) was 44.7%. The PVTT size (<30 vs. 30mm) and BED (<58 vs. 58Gy(10)) were significant factors for tumor response. The median survival and 1-year survival rate were 9.6months and 39.4%. The Child-Pugh classification (A vs. B) and BED were significant factors for survival.

CONCLUSIONS

CRT is effective not only for tumor response but also for survival in HCC-PVTT patients in whom other treatment modalities are not indicated.

The prediction of radiation-induced liver dysfunction using a local dose and regional venous perfusion model

We have shown that high dose conformal radiation combined with chemotherapy appears to prolong the survival of patients with unresectable intrahepatic cancers. The ability to safely deliver higher doses is primarily limited by the development of radiation-induced liver disease, characterized by venous occlusion. In this study, we investigated whether portal venous perfusion measured prior to the end of radiation therapy (RT) together with dose could predict liver venous perfusion dysfunction after treatment. Ten patients with unresectable intrahepatic cancer participated in an IRB-approved computer tomography (CT) perfusion study. Hepatic arterial and portal vein perfusion distributions were estimated by using dynamic contrast enhanced CT and the single compartmental model. Scans were obtained at four time points: prior to treatment, after 15 and 30 fractions of 1.5 Gy treatments, and one month following the completion of RT. Multivariant linear regression was used to determine covariances among the first three time point measurements plus dose for prediction of the post RT measurement. The reduction in the regional venous perfusion one month following RT was predicted by the local accumulated dose and the change in the regional venous perfusion after -30 fractions (F=90.6,p <0.000 01). Each Gy produced an approximately 1.2% of reduction in the venous perfusion. This local dose and venous perfusion model has the potential to predict individual sensitivity to radiation. This is the first step toward developing a method to deliver higher and potentially more curative radiation doses to the patients who can safely receive these higher doses.

Individualized image guided iso-NTCP based liver cancer SBRT

A highly individualized stereotactic body radiotherapy (SBRT) strategy was developed to allow a wide spectrum of patients with liver cancer to be treated. This phase I/II study encompasses individualization of immobilization, radiation planning, PTV margin determination, image guidance strategy and prescription dose. Active breathing control breath hold is used to immobilize the liver when feasible. Image guidance strategies include orthogonal MV images and orthogonal kV fluoroscopy using the diaphragm for a surrogate for the liver, and kV cone beam CT using the liver or tumour for guidance. The prescription dose is individualized to maintain the same estimated risk of radiation-induced liver disease (RILD), based on a normal tissue complication probability (NTCP) model, with a maximum permitted dose of 60 Gy in 6 fractions. Since August 2003, 79 patients with hepatocellular carcinoma (33), intrahepatic cholangiocarcinoma (12) and liver metastases (34) were treated. The median tumour volume was 293 cm3 (2.9-3 088 cm3). The median prescribed dose was 36.6 Gy (24.0 Gy-57.0 Gy) in 6 fractions. The median effective liver volume irradiated was 45% (9-80%). Sixty percent of patients were treated with breath hold to immobilize their liver. Intra-fraction reproducibility (sigma) of the liver with repeat breath holds was excellent (1.5 mm); however inter-fraction reproducibility (sigma) was worse (3.4 mm). Image guidance reduced the residual systematic and random setup errors significantly.

Radiochemotherapy followed by gemcitabine and capecitabine in extrahepatic bile duct cancer: a phase I/II trial

OBJECTIVE

Both radiotherapy and chemotherapy with gemcitabine and capecitabine have efficacy in biliary cancer. Our aim was to determine the toxicity and efficacy of a postoperative regimen combining both treatment modalities in extrahepatic bile duct cancer.

METHODS

Patients were eligible after surgery for extrahepatic bile duct adenocarcinoma. Surgery included resection of lymph node positive cancer, incomplete resections and diagnostic laparotomy in unresectable tumors. Patients received a fractionated radiotherapy of 49.6 Gy accompanied by gemcitabine once a week. After a 2-week rest, patients were treated with gemcitabine and capecitabine on a 3-week cycle. The treatment continued for 6 cycles in nonmeasurable disease or until disease progression or intolerable toxicity.

RESULTS

There were 18 patients (resection/laparotomy 7/11) enrolled between August 2003 and April 2005. Radiotherapy was completed in all patients and a total of 66 cycles of chemotherapy was applied. Fatigue and nausea were the most common mild adverse events. Grade 3 and 4 toxicity was rare after resection but frequent in unresectable disease and consisted of fatigue, nausea, duodenal ulcer, cachexia, and cholangitis in 1, 2, 2, 4, and 4 patients, respectively. We observed a 50% disease stabilization rate in patients with measurable disease. Median overall survival was 7.9 months in patients with unresectable tumors. Median overall survival in patients after resection has not been reached at a median follow-up of 19.5 months.

CONCLUSIONS

Radiochemotherapy using gemcitabine followed by gemcitabine and capecitabine is an active regimen with manageable toxicity after resection of extrahepatic bile duct cancer but has significant toxicity in unresectable disease.

Molecular pathogenesis of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common life-threatening malignancies in the world. This cancer generally arises within the boundaries of well-defined causal factors, of which viral hepatitis infection, aflatoxin exposure, chronic alcohol abuse, and nonalcoholic steatohepatitis are the major risk factors. Despite the identification of these etiological agents, hepatocarcinogenesis remains poorly understood. The molecular mechanisms leading to the development of HCC appear extremely complex and only recently have begun to be elucidated. Currently, surgical resection or liver transplantation offer the best chance of cure for the patient with HCC; however, these therapies are hindered by inability of many of these patients to undergo liver resection, by tumor recurrence and by donor shortages. A lack of suitable therapeutic strategies has led to a greater focus on prevention of HCC using antiviral agents and vaccination. Overall, the current outlook for patients with HCC is bleak; however, a better understanding of the molecular and genetic basis of this cancer should lead to the development of more efficacious therapies.

Retrospective Study of Capecitabine and Celecoxib In Metastatic Colorectal Cancer

OBJECTIVE

COX-2 activation may mediate capecitabine induced toxicities, eg, hand-foot syndrome (HFS) and colorectal cancer progression, both of which may be improved by concurrent celecoxib.

PATIENTS AND METHODS

From October 2000 to December 2003, 66 patients with metastatic colorectal cancer received concurrent capecitabine at 1000 mg/m/d b.i.d. and celecoxib at 200 mg b.i.d. (XCEL). Twenty-four patients were chemo-naive, 42 patients were second-line; while 34 had XCEL with radiation.

RESULTS

The median duration of XCEL was 7.2 months (range, 1.5-38 months). Ninety percent of Grade 2/3 HFS (17%) occurred after 6 months and incidence of grade 3/4 diarrheas was 8%. The overall response rate was 38% (95% confidence interval [CI], 26-51%), with 11 patients (17%) achieving complete responses and 2 patients (3%) with near complete responses. Six patients (9%) become resectable after sustaining treatment response. The median progression-free survival (PFS) and overall survival (OS) was 8.3 months (95% CI, 7.0-11.0 months) and 22 months (95% CI, 17.8-31.5 months), respectively. Improved median PFS of 14.5 months (P = 0.0001) and OS of 31.5 months (P = 0.005) were noted in patients with normal lactate dehydrogenase (LDH) levels (n = 37) than patients with high levels of LDH (n = 29).

CONCLUSIONS

XCEL integrating radiation may improve response rate and survival and reduce toxicities, notably HFS for patients with metastatic colorectal cancer, leading to a randomized phase III study.

Radiation therapy for hepatocellular carcinoma: from palliation to cure

Technologic advances have provided the means to deliver tumoricidal doses of radiation therapy (RT) to patients with unresectable hepatocellular carcinoma (HCC) while avoiding critical normal tissues, providing the opportunity to use RT for curative intent treatment of HCC. For the current report, the expanded role of external beam RT in the setting of HCC from palliation to cure was reviewed. A systematic literature search was undertaken using the MEDLINE data base and secondary references to identify peer-reviewed, English-language articles that reported clinical outcomes after external beam RT alone or in combination with other treatments for HCC. Abstracts from the 2005 American Society of Clinical Oncology, American Society for Therapeutic Radiology and Oncology, American Gastrointestinal Association, and Society of Surgical Oncology Gastrointestinal Cancer Symposium also were included in the search. More than 60 articles reporting on clinical outcomes among patients who received RT for HCC have been published since 1990, including 20 articles that described unique sets of at least 15 patients. RT was used for palliation, to improve local control, and with curative intent in a wide spectrum of patients who most often were unsuitable for surgery and other treatments. Pain reduction following RT was noted in approximately 75% of patients with bone metastases from HCC who received RT. For patients with liver-confined disease treated with conformal RT, proton beam RT, and/or image guided RT with or without transarterial chemoembolization (TACE), local control response rates ranged from 40% to 90%, and the median survival ranges from 10 months to 25 months. For patients with HCC who had portal vein thrombus, the median survival after RT to treat the thrombus and/or the hepatic tumor with or without TACE ranged from 5.3 months to 9.7 months. Although outcomes after high-dose conformal RT for liver-confined HCC were excellent, the potential survival benefit of RT should be tested in randomized controlled trials that require international collaboration.