ABSTRACT
Recently, the superiority of atezolizumab plus bevacizumab (AteBeva) over sorafenib was proven in the IMbrave150 trial, and AteBeva became the first-line systemic treatment for untreated, unresectable hepatocellular carcinoma (HCC). While the results are encouraging, more than half of patients with advanced HCC are still being treated in a palliative setting. Radiotherapy (RT) is known to induce immunogenic effects that may enhance the therapeutic efficacy of immune checkpoint inhibitors. Herein, we report the case of a patient with advanced HCC with massive portal vein tumor thrombosis treated with a combination of RT and AteBeva, who showed near complete response in tumor thrombosis and favorable response to HCC. Although this is a rare case, it shows the importance of reducing the tumor burden via RT to combination immunotherapy in patients with advanced HCC.
ABSTRACT
Hepatocellular carcinoma (HCC) is a highly lethal cancer with limited treatment options and poor prognosis. Carbon ion radiotherapy (CIRT) has emerged as a promising treatment modality for HCC due to its unique physical and biological properties. CIRT uses carbon ions to target and destroy cancer cells with a high precision and efficacy. The Bragg Peak phenomenon allows precise dose delivery to the tumor while minimizing damage to healthy tissues. In addition, the high relative biological effectiveness of carbon ions can be shown against radioresistant and hypoxic tumor areas. CIRT also offers a shorter treatment schedule than conventional radiotherapy, which increases patient convenience and compliance. The clinical outcomes of CIRT for HCC have shown excellent local control rates with minimal side effects. Considering its physical and biological properties, CIRT may be a viable option for complex clinical scenarios such as patients with poor liver function, large tumors, re-irradiation cases, and tumors close to critical organs. Further research and larger studies are needed to establish definitive indications for CIRT and to compare its efficacy with that of other treatment modalities. Nevertheless, CIRT offers a potential breakthrough in HCC management, providing hope for improved therapeutic outcomes and reduced treatment-related toxicities.
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Purpose@#The optimal timing for radiotherapy (RT) after incomplete transarterial chemoembolization (TACE) remains unclear. This study investigated the optimal timing to initiate RT after incomplete TACE in patients with Barcelona Clinic Liver Cancer stage B hepatocellular carcinoma. @*Materials and Methods@#This study included 116 lesions in 104 patients who were treated with RT after TACE between 2001 and 2016. The time interval between the last TACE session and RT initiation was retrospectively analyzed. The optimal cut-off time interval that maximized the difference in local failure-free rates (LFFRs) was determined using maximally selected rank statistics. @*Results@#The median time interval was 26 days (range: 2–165 days). At a median follow-up of 18 months (range: 3–160 months), the median overall survival was 18 months. The optimal cut-off time interval appeared to be 5 weeks; using this cut-off, 65 and 39 patients were classified into early and late RT groups, respectively. Early RT group had a significantly poorer Child-Pugh class and higher alpha-fetoprotein levels compared to late RT group. Other characteristics, including tumor size (7 cm vs. 6 cm; p=0.144), were not significantly different between the groups. The 1-year LFFR was significantly higher in the early RT group than in the late RT group (94.6% vs. 70.8%; p=0.005). On multivariate analysis, early RT was identified as an independent predictor of favorable local failure-free survival (hazard ratio: 3.30, 95% confidence interval: 1.50–7.29; p=0.003). @*Conclusion@#The optimal timing for administering RT after incomplete TACE is within 5 weeks. Early administration of RT is associated with better local control.
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Purpose@#Radiation-induced lymphopenia is associated with worse outcomes in solid tumors. We assessed the impact of interleukin-7 (IL-7), a key cytokine in lymphocyte homeostasis, on radiation-induced lymphopenia. @*Materials and Methods@#A post-hoc analysis was performed in a prospective cohort of 98 patients with hepatocellular carcinoma who were treated with radiotherapy in 2016-2018. Blood IL-7 levels were assayed before and at the end of radiotherapy. Acute severe lymphopenia (ASL) was defined as a total lymphocyte count of < 200/μL during radiotherapy. Cox and logistic regression analyses were performed to identify predictors of survival and ASL development, respectively. @*Results@#Patients with ASL (n=41) had significantly poorer overall survival than those without (12.0 months vs. 25.3 months, p=0.001). Patients with lymphocyte recovery showed significantly longer overall survival than those without (21.8 months vs. 10.3 months, p=0.042). ASL was an independent predictor of poor survival (hazard ratio, 2.07; p=0.015). Patients with ASL had significantly lower pre-radiotherapy IL-7 levels (2.07 pg/mL vs. 3.01 pg/mL, p=0.010). A high pre-radiotherapy IL-7 level was an independent predictor of a reduced risk of ASL development (hazard ratio, 0.40; p=0.004). IL-7 levels reflected a feedback response to ASL, with a higher ΔIL-7 in patients with ASL and a lower ΔIL-7 in those without ASL (0.48 pg/mL vs. –0.66 pg/mL, p < 0.001). Post-radiotherapy IL-7 levels were significantly positively correlated with the total lymphocyte counts at 2 months. @*Conclusion@#IL-7 is associated with the development of and recovery from ASL, which may impact survival. To overcome radiation-induced lymphopenia, a novel strategy using IL-7 may be considered.
ABSTRACT
The clinical efficacy of local ablative treatment for oligometastasis is widely accepted in most cancers. However, due to limited data, this has not been the case for hepatocellular carcinoma (HCC). Here, we report a case of pulmonary oligometastasis of a huge HCC that was treated by multimodality with liver-directed concurrent chemoradiotherapy (CCRT) plus subsequent resection of the primary lesion and local ablative radiotherapy (RT) for subsequent lung oligometastatic lesions. In this patient, liver-directed CCRT induced significant tumor shrinkage with compensatory hypertrophy of the non-tumor liver, followed by curative resection. Surgical resection of the first and second pulmonary metastatic lesions as well as local ablative RT of the third lesion achieved complete tumor regression, which led to long-term survival of 6 years. Therefore, the active use of local ablative RT requires full consideration in cases of oligometastatic HCC.
ABSTRACT
Hepatocellular carcinoma (HCC) with distant metastasis is an absolute contraindication for liver transplantation (LT). However, it is still unclear whether LT is feasible or acceptable in such patients, albeit after being treated with a multidisciplinary approach and after any metastatic lesion is ruled out. We report one such successful treatment with living donor LT (LDLT) after completely controlling far-advanced HCC with inferior vena cava tumor thrombosis and multiple lung metastases. The patient has been doing well without HCC recurrence for eight years since LDLT. The current patient could be an anecdotal case, but provides a case for expanding LDLT indications in the context of advanced HCC and suchlike.
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Purpose@#The optimal timing for radiotherapy (RT) after incomplete transarterial chemoembolization (TACE) remains unclear. This study investigated the optimal timing to initiate RT after incomplete TACE in patients with Barcelona Clinic Liver Cancer stage B hepatocellular carcinoma. @*Materials and Methods@#This study included 116 lesions in 104 patients who were treated with RT after TACE between 2001 and 2016. The time interval between the last TACE session and RT initiation was retrospectively analyzed. The optimal cut-off time interval that maximized the difference in local failure-free rates (LFFRs) was determined using maximally selected rank statistics. @*Results@#The median time interval was 26 days (range: 2–165 days). At a median follow-up of 18 months (range: 3–160 months), the median overall survival was 18 months. The optimal cut-off time interval appeared to be 5 weeks; using this cut-off, 65 and 39 patients were classified into early and late RT groups, respectively. Early RT group had a significantly poorer Child-Pugh class and higher alpha-fetoprotein levels compared to late RT group. Other characteristics, including tumor size (7 cm vs. 6 cm; p=0.144), were not significantly different between the groups. The 1-year LFFR was significantly higher in the early RT group than in the late RT group (94.6% vs. 70.8%; p=0.005). On multivariate analysis, early RT was identified as an independent predictor of favorable local failure-free survival (hazard ratio: 3.30, 95% confidence interval: 1.50–7.29; p=0.003). @*Conclusion@#The optimal timing for administering RT after incomplete TACE is within 5 weeks. Early administration of RT is associated with better local control.
ABSTRACT
The clinical efficacy of local ablative treatment for oligometastasis is widely accepted in most cancers. However, due to limited data, this has not been the case for hepatocellular carcinoma (HCC). Here, we report a case of pulmonary oligometastasis of a huge HCC that was treated by multimodality with liver-directed concurrent chemoradiotherapy (CCRT) plus subsequent resection of the primary lesion and local ablative radiotherapy (RT) for subsequent lung oligometastatic lesions. In this patient, liver-directed CCRT induced significant tumor shrinkage with compensatory hypertrophy of the non-tumor liver, followed by curative resection. Surgical resection of the first and second pulmonary metastatic lesions as well as local ablative RT of the third lesion achieved complete tumor regression, which led to long-term survival of 6 years. Therefore, the active use of local ablative RT requires full consideration in cases of oligometastatic HCC.
ABSTRACT
Hepatocellular carcinoma (HCC) with distant metastasis is an absolute contraindication for liver transplantation (LT). However, it is still unclear whether LT is feasible or acceptable in such patients, albeit after being treated with a multidisciplinary approach and after any metastatic lesion is ruled out. We report one such successful treatment with living donor LT (LDLT) after completely controlling far-advanced HCC with inferior vena cava tumor thrombosis and multiple lung metastases. The patient has been doing well without HCC recurrence for eight years since LDLT. The current patient could be an anecdotal case, but provides a case for expanding LDLT indications in the context of advanced HCC and suchlike.
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PURPOSE: To investigate noninvasive biomarkers for predicting treatment response in patients with locally advanced HCC who underwent concurrent chemoradiotherapy (CCRTx).MATERIALS AND METHODS: Thirty patients (55.5 ± 10.2 years old, M:F = 24:6) who underwent CCRTx due to advanced HCC were enrolled. Contrast-enhanced US (CEUS) and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) were obtained before and immediately after CCRTx. The third CEUS was obtained at one month after CCRTx was completed. Response was assessed at three months after CCRTx based on RECIST 1.1. Quantitative imaging biomarkers measured with CEUS and MRI were compared between groups. A cutoff value was calculated with ROC analysis. Overall survival (OS) was compared by the Breslow method.RESULTS: Twenty-five patients were categorized into the non-progression group and five patients were categorized into the progression group. Peak enhancement of the first CEUS before CCRTx (PE1) was significantly lower in the non-progression group (median, 18.6%; IQR, 20.9%) than that in the progression group (median, 59.1%; IQR, 13.5%; P = 0.002). There was no significant difference in other quantitative biomarkers between the two groups. On ROC analysis, with a cutoff value of 42.6% in PE1, the non-progression group was diagnosed with a sensitivity of 90.9% and a specificity of 100%. OS was also significantly longer in patients with PE1 < 42.6% (P = 0.014).CONCLUSION: Early treatment response and OS could be predicted by PE on CEUS before CCRTx in patients with HCC.
Subject(s)
Humans , Biomarkers , Carcinoma, Hepatocellular , Chemoradiotherapy , Magnetic Resonance Imaging , Methods , Perfusion Imaging , Response Evaluation Criteria in Solid Tumors , ROC Curve , Sensitivity and Specificity , UltrasonographyABSTRACT
PURPOSE: There is limited data on radiotherapy (RT) for hepatocellular carcinoma (HCC) in patients with Child-Pugh classification B (CP-B). This study aimed to evaluate the treatment outcomes of fractionated conformal RT in HCC patients with CP-B. MATERIALS AND METHODS: We retrospectively reviewed the data of HCC patients with CP-B treated with RT between 2009 and 2014 at 13 institutions in Korea. HCC was diagnosed by the Korea guideline of 2009, and modern RT techniques were applied. Fraction size was ≤ 5 Gy and the biologically effective dose (BED) ≥ 40 Gy₁₀ (α/β = 10 Gy). A total of 184 patients were included in this study. RESULTS: Initial CP score was seven in 62.0% of patients, eight in 31.0%, and nine in 7.0%. Portal vein tumor thrombosis was present in 66.3% of patients. The BED ranged from 40.4 to 89.6 Gy₁₀ (median, 56.0 Gy₁₀). After RT completion, 48.4% of patients underwent additional treatment. The median overall survival (OS) was 9.4 months. The local progression-free survival and OS rates at 1 year were 58.9% and 39.8%, respectively. In the multivariate analysis, non-classic radiation-induced liver disease (RILD) (p < 0.001) and additional treatment (p < 0.001) were the most significant prognostic factors of OS. Among 132 evaluable patients without progressive disease, 19.7% experienced non-classic RILD. Normal liver volume was the most predictive dosimetric parameter of non-classic RILD. CONCLUSION: Fractionated conformal RT showed favorable OS with a moderate risk non-classic RILD. The individual radiotherapy for CP-B could be cautiously applied weighing the survival benefits and the RILD risks.
Subject(s)
Humans , Carcinoma, Hepatocellular , Classification , Disease-Free Survival , Korea , Liver , Liver Diseases , Multivariate Analysis , Portal Vein , Radiotherapy , Radiotherapy, Conformal , Retrospective Studies , Thrombosis , Treatment OutcomeABSTRACT
Stereotactic body radiotherapy (SBRT) is a form of radiotherapy that delivers high doses of irradiation with high precision in a small number of fractions. However, it has not frequently been performed for the liver due to the risk of radiation-induced liver toxicity. Furthermore, liver SBRT is cumbersome because it requires accurate patient repositioning, target localization, control of breathing-related motion, and confers a toxicity risk to the small bowel. Recently, with the advancement of modern technologies including intensity-modulated RT and image-guided RT, SBRT has been shown to significantly improve local control and survival outcomes for hepatocellular carcinoma (HCC), specifically those unfit for other local therapies. While it can be used as a stand-alone treatment for those patients, it can also be applied either as an alternative or as an adjunct to other HCC therapies (e.g., transarterial chemoembolization, and radiofrequency ablation). SBRT might be an effective and safe bridging therapy for patients awaiting liver transplantation. Furthermore, in recent studies, SBRT has been shown to have a potential role as an immunostimulator, supporting the novel combination strategy of immunoradiotherapy for HCC. In this review, the role of SBRT with some technical issues is discussed. In addition, future implications of SBRT as an immunostimulator are considered.
Subject(s)
Humans , Carcinoma, Hepatocellular , Immunotherapy , Liver , Liver Transplantation , Moving and Lifting Patients , Radioimmunotherapy , Radiosurgery , Radiotherapy , Radiotherapy, Intensity-ModulatedABSTRACT
PURPOSE: Early prediction of treatment outcomes represents an essential step towards increased treatment efficacy and survival in patients with hepatocellular carcinoma (HCC). In this study, we performed two-dimensional electrophoresis (2-DE) followed by protein profiling to identify biomarkers predictive of therapeutic outcomes in patients with HCC who received liver-directed therapy (LDTx) involving local radiotherapy (RT), and studied the underlying mechanisms of the identified proteins. MATERIALS AND METHODS: 2-DE analysis was conducted by pooling sera from patients with a good or poor prognosis; serum proteomic profiles of the two groups were compared and analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Identified proteins were confirmed via enzyme-linked immunosorbent assay. An invasion assay was performed after overexpression and knockdown of target protein in Huh7 cells. RESULTS: Levels of inter-alpha inhibitor H4 (ITIH4), fibrinogen gamma chain, keratin 9/1 complex, carbonic anhydrase I, and carbonmonoxyhemoglobin S were changed by more than 4-fold in response to LDTx. In particular, pre-LDTx ITIH4 expression was more than 5-fold higher in patients with a good prognosis, compared to patients with a poor prognosis. The migration ability of Huh7 cells was significantly suppressed and enhanced by ITIH4 overexpression and knockdown, respectively. The tumors of patients with HCC and a good prognosis expressed high levels of ITIH4, compared to those of patients with a poor prognosis. CONCLUSION: Taken together, ITIH4 may be a potential therapeutic target that could inhibit cancer metastasis, as well as a prognostic marker for patients with HCC who are receiving LDTx.
Subject(s)
Humans , Biomarkers , Carbonic Anhydrase I , Carboxyhemoglobin , Carcinoma, Hepatocellular , Electrophoresis , Enzyme-Linked Immunosorbent Assay , Fibrinogen , Mass Spectrometry , Neoplasm Metastasis , Prognosis , Radiotherapy , Treatment OutcomeABSTRACT
PURPOSE: Cell-free DNA (cfDNA) is gaining attention as a novel biomarker for oncologic outcomes. We investigated the clinical significance of cfDNA in hepatocellular carcinoma (HCC) patients treated with radiotherapy (RT). MATERIALS AND METHODS: Fifty-five patients with HCC who received RT were recruited from two prospective study cohorts: one cohort of 34 patients who underwent conventionally fractionated RT and a second of 21 patients treated with stereotactic body radiation therapy. cfDNA was extracted and quantified. RESULTS: In total, 30% of the patients had multiple tumors, 77% had tumors >2 cm, and 32% had portal vein tumor thrombus. Optimal cut-off values for cfDNA levels (33.65 ng/mL and 37.25 ng/mL, before and after RT) were used to divide patients into low-DNA (LDNA) and high-DNA (HDNA) groups. The pre-RT HDNA group tended to have more advanced disease and larger tumors (p=0.049 and p=0.017, respectively). Tumor response, intrahepatic failure-free rates, and local control (LC) rates were significantly better in the post-RT LDNA group (p=0.017, p=0.035, and p=0.006, respectively). CONCLUSION: Quantitative analysis of cfDNA was feasible in our cohorts. Post-RT cfDNA levels were negatively correlated with treatment outcomes, indicating the potential for the use of post-RT cfDNA levels as an early predictor of treatment responses and LC after RT for HCC patients.
Subject(s)
Humans , Biomarkers , Carcinoma, Hepatocellular , Cohort Studies , DNA , Plasma , Portal Vein , Prospective Studies , Radiotherapy , ThrombosisABSTRACT
With increasing clinical use, radiotherapy (RT) has been considered reliable and effective method for hepatocellular carcinoma (HCC) treatment, depending on extent of disease and patient characteristics. RT for HCC can improve therapeutic outcomes through excellent local control, downstaging, conversion from unresectable to resectable status, and treatments of unresectable HCCs with vessel invasion or multiple intrahepatic metastases. In addition, further development of modern RT technologies, including image-guided radiotherapy (IGRT), intensity-modulated radiotherapy (IMRT), and stereotactic body radiotherapy, has expanded the indication of RT. An essential feature of IGRT is that it allows image guidance therapy through in-room images obtained during radiation delivery. Compared with 3D-conformal RT, distinctions of IMRT are inverse treatment planning process and use of a large number of treatment fields or subfields, which provide high precision and exquisitely conformal dose distribution. These modern RT techniques allow more precise treatment by reducing inter- and intra-fractional errors resulting from daily changes and irradiated dose at surrounding normal tissues. More recently, particle therapy has been actively investigated to improve effectiveness of RT. This review discusses modern RT strategies for HCC, as well as optimal selection of RT in multimodal approach for HCC.
Subject(s)
Humans , Carcinoma, Hepatocellular , Methods , Neoplasm Metastasis , Radiosurgery , Radiotherapy , Radiotherapy, Image-Guided , Radiotherapy, Intensity-ModulatedABSTRACT
BACKGROUND/AIMS: We investigated whether inflammatory markers such as neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) independently and in combination would be significant prognostic factors for survival in patients with locally advanced pancreatic cancer. METHODS: A total of 497 patients with locally advanced pancreatic cancer who received neoadjuvant or definitive chemoradiotherapy from 2005 to 2015 were evaluated. We divided the patients into groups according to the median values of NLR and PLR: NLR < 1.89 (n=156), NLR≥1.89 (n=341), PLR < 149 (n=248) and PLR≥149 (n=249). RESULTS: For NLR < 1.89 and ≥1.89 groups, respectively, the 1-year overall survival (OS) rates were 73.2% and 60.8% (p < 0.001) and 1-year progression-free survival (PFS) rates were 43.9% and 31.3% (p < 0.001). For PLR < 149 and ≥149 groups, respectively, the 1-year OS rates were 68.1% and 61.3% (p=0.029) and 1-year PFS rates were 37.9% and 32.5% (p=0.027). Patients with both high NLR and high PLR showed the worst OS and PFS rates compared with those with both lower NLR and lower PLR. CONCLUSIONS: Elevated pretreatment NLR and PLR independently and in combination significantly predicted poor OS and PFS.
Subject(s)
Humans , Chemoradiotherapy , Disease-Free Survival , Lymphocyte Count , Neutrophils , Pancreatic Neoplasms , Platelet Count , PrognosisABSTRACT
PURPOSE: The aim of this study was to examine patterns of radiotherapy (RT) in Korean patients with hepatocellular carcinoma (HCC) according to the evolving guideline for HCC established by the Korean Liver Cancer Study Group-National Cancer Center (KLCSG-NCC). MATERIALS AND METHODS: We reviewed 765 patients with HCC who were treated with RT between January 2011 and December 2012 in 12 institutions. RESULTS: The median follow-up period was 13.3 months (range, 0.2 to 51.7 months). Compared with previous data between 2004 and 2005, the use of RT as a first treatment has increased (9.0% vs. 40.8%). Increased application of intensity-modulated RT resulted in an increase in radiation dose (fractional dose, 1.8 Gy vs. 2.5 Gy; biologically effective dose, 53.1 Gy10 vs. 56.3 Gy10). Median overall survival was 16.2 months, which is longer than that reported in previous data (12 months). In subgroup analysis, treatments were significantly different according to stage (p < 0.001). Stereotactic body RT was used in patients with early HCC, and most patients with advanced stage were treated with three-dimensional conformal RT. CONCLUSION: Based on the evolving KLCSG-NCC practice guideline for HCC, clinical practice patterns of RT have changed. Although RT is still used mainly in advanced HCC, the number of patients with good performance status who were treated with RT as a first treatment has increased. This change in practice patterns could result in improvement in overall survival.
Subject(s)
Humans , Carcinoma, Hepatocellular , Follow-Up Studies , Liver Neoplasms , Practice Patterns, Physicians' , Radiation Oncology , RadiotherapyABSTRACT
BACKGROUND/AIMS: Hepatocellular carcinoma (HCC) patients with spinal metastasis (SM) show heterogeneous lengths of survival. In this study, we develop and propose a graded prognostic assessment for HCC patients with SM (HCC-SM GPA). METHODS: We previously reported the outcomes of 192 HCC patients with SM who received radiotherapy from April 1992 to February 2012. Prognostic factors that significantly affected survival in that study were used to establish the HCC-SM GPA. Validation was performed using an independent cohort of 63 patients recruited from September 2011 to March 2016. RESULTS: We developed the HCC-SM GPA using the following factors: Eastern Cooperative Oncology Group performance status (0–2, 0 point; 3–4, 1 point), controlled primary HCC (yes, 0 point; no, 2 points), and extrahepatic metastases other than bone (no, 0 point; yes, 1 point). Patients were stratified into low (GPA=0), intermediate (GPA=1 to 2), and high risk (GPA=3 to 4). When applied to the validation cohort, the HCC-SM GPA determined median survival durations of 13.6, 4.8, and 2.6 months and 1-year overall survival rates of 58.3%, 17.8%, and 7.3% for the low-, intermediate-, and high-risk patient groups, respectively (p<0.001). CONCLUSIONS: Our newly proposed HCC-SM GPA successfully predicted survival outcomes.
Subject(s)
Humans , Carcinoma, Hepatocellular , Cohort Studies , Neoplasm Metastasis , Radiotherapy , Survival RateABSTRACT
BACKGROUND/AIMS: As the optimal stereotactic body radiation therapy (SBRT) modality for hepatocellular carcinoma (HCC) has not been confirmed, we aimed herein to provide a practical guideline by our retrospective review. METHODS: Thirty-nine patients with primary HCC who underwent liver SBRT via 3 modalities (helical tomotherapy [HT]: 22, volumetric modulated arc therapy [VMAT]: 13, Cyberknife: 4) at our institution between July 2014 and July 2015 were included. Modalities were compared with regard to dose conformity index (CI), homogeneity index (HI), clinical results, and patient compliance. RESULTS: VMAT SBRT had favorable conformity (CI: 0.7±0.2), homogeneity (HI: 1.1±0.0), and shortest treatment time (100.2±26.1 seconds). HT SBRT yielded good dosimetric outcomes, especially in conformity (CI: 1.0±0.2). Although the Cyberknife SBRT synchrony system allowed real-time tumor targeting, the treatment time was longest (3,015.0±447.3 seconds), invasive pre-treatment procedures were required, and the HI (1.3±0.0) was lowest. CONCLUSIONS: All 3 modalities yielded competent dosimetric planning parameters. VMAT SBRT was most appropriate for tumors with residual lipiodol or patients with poor conditions. HT SBRT is available for multiple or irregular targets. Cyberknife SBRT is recommended for carefully selected patients and tumors indicated for sono-guided fiducial insertion.
Subject(s)
Humans , Carcinoma, Hepatocellular , Ethiodized Oil , Liver , Patient Compliance , Radiotherapy , Radiotherapy, Intensity-Modulated , Retrospective StudiesABSTRACT
PURPOSE: This study aimed to evaluate whether the deformable image registration (DIR) method is clinically applicable to the safe delivery of re-irradiation in hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Between August 2010 and March 2012, 12 eligible HCC patients received re-irradiation using helical tomotherapy. The median total prescribed radiation doses at first irradiation and re-irradiation were 50 Gy (range, 36-60 Gy) and 50 Gy (range, 36-58.42 Gy), respectively. Most re-irradiation therapies (11 of 12) were administered to previously irradiated or marginal areas. Dose summation results were reproduced using DIR by rigid and deformable registration methods, and doses of organs-at-risk (OARs) were evaluated. Treatment outcomes were also assessed. RESULTS: Thirty-six dose summation indices were obtained for three OARs (bowel, duodenum, and stomach doses in each patient). There was no statistical difference between the two different types of DIR methods (rigid and deformable) in terms of calculated summation operatorD (0.1 cc, 1 cc, 2 cc, and max) in each OAR. The median total mean remaining liver doses (M(RLD)) in rigid- and deformable-type registration were not statistically different for all cohorts (p=0.248), although a large difference in M(RLD) was observed when there was a significant difference in spatial liver volume change between radiation intervals. One duodenal ulcer perforation developed 20 months after re-irradiation. CONCLUSION: Although current dose summation algorithms and uncertainties do not warrant accurate dosimetric results, OARs-based DIR dose summation can be usefully utilized in the re-irradiation of HCC. Appropriate cohort selection, watchful interpretation, and selective use of DIR methods are crucial to enhance the radio-therapeutic ratio.