Darren M.C. Poon

Management of hepatocellular carcinoma with portal vein tumor thrombosis: Review and update at 2016

Portal vein tumor thrombosis (PVTT) is a common phenomenon in hepatocellular carcinoma (HCC). Compared to HCC without PVTT, HCC with PVTT is characterized by an aggressive disease course, worse hepatic function, a higher chance of complications related to portal hypertension and poorer tolerance to treatment. Conventionally, HCC with PVTT is grouped together with metastatic HCC during the planning of its management, and most patients are offered palliative treatment with sorafenib or other systemic agents. As a result, most data on the management of HCC with PVTT comes from subgroup analyses or retrospective series. In the past few years, there have been several updates on management of HCC with PVTT. First, it is evident that HCC with PVTT consists of heterogeneous subgroups with different prognoses. Different classifications have been proposed to stage the degree of portal vein invasion/thrombosis, suggesting that different treatment modalities may be individualized to patients with different risks. Second, more studies indicate that more aggressive treatment, including surgical resection or locoregional treatment, may benefit select HCC patients with PVTT. In this review, we aim to discuss the recent conceptual changes and summarize the data on the management of HCC with PVTT.

Use of antiviral therapy in surveillance: impact on outcome of hepatitis B-related hepatocellular carcinoma.

Antiviral therapy for hepatitis B virus (HBV) infection is frequently prescribed for patients with chronic HBV infection during surveillance for hepatocellular carcinoma (HCC). In patients who subsequently develop HCC, the impact of antiviral therapy on the outcome of HCC remains unclear.

Dosimetric Advantages and Superior Treatment Delivery Efficiency of RapidArc over Conventional Intensity-modulated Radiotherapy in High-risk Prostate Cancer Involving Seminal Vesicles and Pelvic Nodes

AIMS To compare the dosimetry and treatment delivery efficiency of RapidArc with conventional intensity-modulated radiotherapy (IMRT) in the treatment of high-risk prostate cancer. MATERIALS AND METHODS Fifteen patients with high-risk localised prostate cancer were studied. Sequential treatment was used. The initial planning target volume (PTV-L) included the prostate, seminal vesicles and pelvic lymphatics, whereas the prostate boost PTV (PTV-P) included the prostate and seminal vesicles only. The total prescription dose was 76 Gy (44 Gy to PTV-L, 32 Gy to PTV-P; 2 Gy/fraction). Two separate planning techniques were generated for each patient: seven static-field IMRT versus two-arc RapidArc. Dose-volume parameters for the organs at risk, conformity index and homogeneity index for the PTVs, the calculated monitor units and treatment delivery time for both techniques were compared. RESULTS RapidArc gave more conformal plans than IMRT for both PTVs. RapidArc gave a higher homogeneity index to the PTV-P and a similar homogeneity index to the PTV-L. The two techniques gave similar dosimetric results for the rectum, bladder and femoral heads. The mean dose (Dmean) and the maximum dose (Dmax) of the bowel space were reduced by 3.06 and 2.83%, respectively, with RapidArc. The V20 Gy, V30 Gy and V40 Gy for healthy tissues were reduced by 7.77, 14.25 and 17.55%, respectively, with RapidArc. The calculated treatment delivery time and monitor units were reduced by 74.09%/60.93% and 68.32%/48.06% for the PTV-L/PTV-P, respectively, with RapidArc. CONCLUSION RapidArc is better than conventional IMRT in terms of dosimetry and delivery efficiency for high-risk prostate cancer.

Treatment outcomes of nasopharyngeal carcinoma in modern era after intensity modulated radiotherapy (IMRT) in Hong Kong: A report of 3328 patients (HKNPCSG 1301 study)

PURPOSE To evaluate treatment outcomes, failure patterns and late toxicities in patients with nasopharyngeal carcinoma (NPC) treated by intensity modulated radiotherapy (IMRT) in 6 public hospitals in Hong Kong over a 10-year period from 2001 to 2010. MATERIAL AND METHODS Eligible patients were identified through the Hong Kong Cancer Registry data base. Clinical information was retrieved and verified by oncologists working in the individual centers. Treatment details, survival outcomes and late toxicities were analyzed. RESULTS A total of 3328 patients were recruited. The median follow-up time was 80.2 months. The 8-year actuarial overall survival (OS), local failure-free survival (LFFS), regional failure-free survival (RFFS), distant failure free survival (DFFS), progression-free survival (PFS) for the whole group was 68.5%, 85.8%, 91.5%, 81.5% and 62.6% respectively. Male gender, older age, advanced T and N stage were adverse prognostic factors for OS, DFFS and PFS, whereas use of chemotherapy in form of concurrent chemo-irradiation (CRT), neoadjuvant + CRT, or CRT + adjuvant chemotherapy were favorable prognostic factors for OS and PFS. The local control was adversely affected by advanced T stage. N stage remained as the single adverse prognostic factor for regional control. Distant metastasis was the commonest site of failure. CONCLUSION IMRT is an effective treatment for NPC with excellent overall loco-regional control. Distant metastasis is the major site of failure. Concurrent chemotherapy with cisplatin has an established role in NPC patients treated by IMRT.

Prediction of distant metastases from nasopharyngeal carcinoma: Improved diagnostic performance of MRI using nodal volume in N1 and N2 stage disease

PURPOSE To determine if the magnetic resonance imaging (MRI) of the head and neck can predict distant metastases (DM) from nasopharyngeal carcinoma (NPC). METHODS AND MATERIALS MRI examinations of 763 NPC patients were assessed for primary tumour stage (T), nodal stage (N), primary tumour volume (PTV) and total nodal volume (NV). The association between MRI and clinical parameters were examined in DM+ and DM- patients using logistic regression and for distant metastases free survival (DMFS) using cox regression. Optimum thresholds were assessed by receiver-operating characteristics analysis, and positive predictive value (PPV) and odds ratio (OR) calculated. RESULTS Distant metastases were present in 181/763 NPC patients (23.7%). Higher N stage and NV were the independent predictors of DM (p<0.001 and 0.018 respectively) and poor DMFS (p=0.001 and 0.030 respectively). Addition of NV (threshold≥32.8cm3) to the N stage improved the PPVs and ORs for DM in stage N1 (from 18.9% to 31.8% and 5.613 to 11.133 respectively) and stage N2 (from 40.4% to 60.8% and 16.189 to 36.979 respectively) but not in stage N3 (68.3% to 68.6% and 51.385 to 52.052 respectively). CONCLUSION MRI N stage and NV were independent predictors of DM and DMFS. The addition of NV in NPC patients with bulky N1 and N2 disease improved the ability of MRI to predict DM.

Ten-year review of survival and management of malignant glioma in Hong Kong

INTRODUCTION Surgical resection used to be the mainstay of treatment for glioma. In the last decade, however, opinion has changed about the goal of surgical resection in treating glioma. Ample evidence shows that maximum safe resection in glioblastoma improves survival. Neurosurgeons have therefore revised their objective of surgery from diagnostic biopsy or limited debulking to maximum safe resection. Given these changes in the management of glioma, we compared the survival of local Chinese patients with glioblastoma multiforme over a period of 10 years. METHODS We retrospectively reviewed the data of the brain tumour registry of the CUHK Otto Wong Brain Tumour Centre in Hong Kong. Data of patients with glioblastoma multiforme were reviewed for two periods, during 1 January 2003 to 31 December 2005 and 1 January 2010 to 31 December 2012. Overall survival during these two periods of time was assessed by Kaplan-Meier survival estimates. Risk factors including age, type and extent of resection, use of chemotherapy, and methylation status of O6-methylguanine-DNA methyltransferase were also assessed. RESULTS There were 26 patients with glioblastoma multiforme with a mean age of 52.2 years during 2003 to 2005, and 42 patients with a mean age of 55.1 years during 2010 to 2012. The mean overall survival during these two periods was 7.4 months and 12.7 months, respectively (P<0.001). The proportion of patients who underwent surgical resection was similar: 69.2% in 2003 to 2005 versus 78.6% in 2010 to 2012 (P=0.404). There was a higher proportion of patients in whom surgery achieved total removal in 2010 to 2012 than in 2003 to 2005 (35.7% and 7.7%, respectively; P=0.015). During 2010 to 2012, patients who were given concomitant chemoradiotherapy showed definitively longer survival than those who were not (17.9 months vs 4.5 months; P=0.001). The proportion of patients who survived 2 years after surgery increased from 11.5% in 2003 to 2005 to 21.4% in 2010 to 2012. CONCLUSIONS Hong Kong has made substantial improvements in the management of glioblastoma multiforme over the last decade with corresponding improved survival outcomes. The combination of an aggressive surgical strategy and concomitant chemoradiotherapy are probably the driving force for the improvement.

Head and Neck Tumors: Amide Proton Transfer MRI

Purpose To evaluate the utility of amide proton transfer (APT) imaging in the characterization of head and neck tumors. Materials and Methods This retrospective study of APT imaging included 117 patients with 70 nasopharyngeal undifferentiated carcinomas (NUCs), 26 squamous cell carcinomas (SCCs), eight non-Hodgkin lymphomas (NHLs), and 13 benign salivary gland tumors (BSGTs). Normal tissues were examined in 25 patients. The APT means of malignant tumors, normal tissues, and benign tumors were calculated and compared with the Student t test and analysis of variance. The added value of the mean APT to the mean apparent diffusion coefficient (ADC) for differentiating malignant and benign tumors was evaluated by using receiver operating characteristic analysis and integrated discrimination index. Results The mean APT of malignant tumors (2.40% ± 0.97 [standard deviation]) was significantly higher than that of brain tissue (1.13% ± 0.43), muscle tissue (0.23% ± 0.73), and benign tumors (1.32% ± 1.20) (P < .001). There were no differences between malignant groups (NUC, 2.37% ± 0.90; SCC, 2.41% ± 1.16; NHL, 2.65% ± 0.89; P = .45 to P = .86). The mean ADC of malignant tumors ([0.85 ± 0.17] × 10-3 mm2/sec) was significantly lower than that of benign tumors ([1.46 ± 0.47] × 10-3 mm2/sec) (P = .001). Adding APT to ADC increased the area under the curve from 0.87 to 0.96, with an integrated discrimination index of 7.6% (P = .13). Conclusion These preliminary data demonstrate differences in amide proton transfer (APT) mean of malignant tumors, normal tissues, and benign tumors, although APT mean could not be used to differentiate between malignant tumor groups. APT imaging has the potential to be of added value to apparent diffusion coefficient in differentiating malignant from benign tumors.

Analysis of Plasma Epstein-Barr Virus DNA in Nasopharyngeal Cancer After Chemoradiation to Identify High-Risk Patients for Adjuvant Chemotherapy: A Randomized Controlled Trial

Purpose The contribution of adjuvant chemotherapy after chemoradiation therapy (CRT) in nasopharyngeal cancer (NPC) remains controversial. Plasma Epstein-Barr virus (EBV) DNA is a potential biomarker of subclinical residual disease in NPC. In this prospective, multicenter, randomized controlled trial, we used plasma EBV DNA to identify patients with NPC at a higher risk of relapse for adjuvant chemotherapy. Patients and Methods Eligible patients with histologically confirmed NPC of Union for International Cancer Control stage IIB to IVB, adequate organ function, and no locoregional disease or distant metastasis were screened by plasma EBV DNA at 6 to 8 weeks after radiotherapy (RT). Patients with undetectable plasma EBV DNA underwent standard surveillance. Patients with detectable plasma EBV DNA were randomly assigned to either adjuvant chemotherapy with cisplatin and gemcitabine for six cycles (arm 1) or observation (arm 2). Patients were stratified for primary treatment (RT v CRT) and stage (II/III v IV). The primary end point was relapse-free survival (RFS). Results Seven hundred eighty-nine patients underwent EBV DNA screening. Plasma EBV DNA was undetectable in 573 (72.6%) and detectable in 216 (27.4%); 104 (13.2%) with detectable EBV DNA were randomly assigned to arms 1 (n = 52) and 2 (n = 52). After a median follow-up of 6.6 years, no significant difference was found in 5-year RFS rate between arms 1 and 2 (49.3% v 54.7%; P = .75; hazard ratio for relapse or death, 1.09; 95% CI, 0.63 to 1.89). The level of post-RT plasma EBV DNA correlated significantly with the hazards of locoregional failure, distant metastasis, and death. Conclusion In patients with NPC with detectable post-RT plasma EBV DNA, adjuvant chemotherapy with cisplatin and gemcitabine did not improve RFS. Post-RT plasma EBV DNA level should be incorporated as the selection factor in future clinical trials of adjuvant therapy in NPC.

Nasopharyngeal carcinoma: relationship between invasion of the prevertebral space and distant metastases

PurposeTo identify primary sites of nasopharyngeal carcinoma (NPC) invasion on the staging head and neck magnetic resonance imaging (MRI) that correlate with distant metastases (DM).Materials and methodsStaging head and neck MRI examinations of 579 NPC patients were assessed for primary tumour invasion into 16 individual sites, primary stage (T) and nodal stage (N). Results were correlated with distant metastasis-free survival (DMFS) using the Cox regression, and the diagnostic performance of significant independent markers for DM was calculated. In addition, sites of primary tumour invasion were correlated also with involvement of the first echelon of ipsilateral nodes (FEN+) using logistic regression.ResultsDistant metastases were present in 128/579 NPC patients (22.1%) after intensity-modulated radiotherapy (IMRT)/chemo-IMRT and 5-year DMFS was 78.8%. Prevertebral space invasion (PVS+) and N stage, but not T stage, were independent prognostic markers of DMFS (p = 0.016, < 0.001, and 0.433, respectively). Compared to stage N3, PVS invasion had a higher sensitivity (28.1 vs. 68.8%), but lower specificity (90.5 vs. 47.4%) and accuracy (76.7 vs. 48.9%) for correlating patients with DM. PVS invasion, together with parapharyngeal fat space invasion (PPFS+), was also an independent predictive marker of FEN+.ConclusionPVS was the only site of primary tumour invasion that independently correlated with DM, and together with PPFS + was an independent prognostic marker of FEN+, but the low specificity and accuracy of PVS invasion limits its use as a prognostic marker of DM.

Feasibility and safety of extended adjuvant temozolomide beyond six cycles for patients with glioblastoma

INTRODUCTION Temozolomide is the first chemotherapeutic agent proven effective for patients with newly diagnosed glioblastoma. The drug is well tolerated for its low toxicity. The current standard practice is concomitant chemoradiotherapy for 6 weeks followed by 6 cycles of adjuvant temozolomide. Some Caucasian studies have suggested that patients might benefit from extended adjuvant cycles of temozolomide (>6 cycles) to lengthen both progression-free survival and overall survival. In the present study, we compared differences in survival and toxicity profile between patients who received conventional 6-cycle temozolomide and those who received more than 6 cycles of temozolomide. METHODS Patients with newly diagnosed glioblastoma without progressive disease and completed concomitant chemoradiotherapy during a 4-year period were studied. Progression-free survival was compared using Kaplan-Meier survival curves. t Test, U test, and correlation were chosen accordingly to examine the impact of age, extent of resection, MGMT promoter methylation status and adjuvant cycles on progression-free survival. For factors with a P value of <0.05 in univariate analyses, Cox regression hazard model was adopted to determine the strongest factors related to progression-free survival. RESULTS The median progression-free survival was 17.0 months for patients who received 6 cycles of temozolomide (n=7) and 43.4 months for those who received more than 6 cycles (n=7) [P=0.007, log-rank test]. Two patients in the former group and one in the latter group encountered grade 1 toxicity and recovered following dose adjustment. Cycles of adjuvant temozolomide were correlated with progression-free survival (P=0.016, hazard ratio=0.68). CONCLUSION Extended cycles of temozolomide are safe and feasible for Chinese patients with disease responsive to temozolomide.