Feasibility and safety of long-term photodynamic therapy (PDT) in the palliative treatment of patients with hilar cholangiocarcinoma

A Systematised Literature Review of Real-World Treatment Patterns and Outcomes in Unresectable Advanced or Metastatic Biliary Tract Cancer

BACKGROUND

Biliary tract cancers are rare aggressive malignancies typically diagnosed when the disease is metastatic or unresectable, precluding curative treatment.

OBJECTIVE

We aimed to identify treatment guidelines, real-world treatment patterns, and outcomes for unresectable advanced or metastatic biliary tract cancers in adult patients.

METHODS

Databases (MEDLINE, Embase, Cochrane Database of Systematic Reviews) were systematically searched between 1 January, 2000 and 25 November, 2021, and supplemented by hand searches. Eligible records were (1) treatment guidelines and (2) observational studies reporting real-world treatment outcomes, for unresectable advanced or metastatic biliary tract cancers. Only studies performed in the UK, Germany, France, Australia, Canada and South Korea were extracted, to moderate the number of records for synthesis while maintaining representation of a wide range of biliary tract cancer incidences.

RESULTS

A total of 66 relevant unique full-text records were extracted, including 16 treatment guidelines and 50 observational studies. Among guidelines, chemotherapies were most strongly recommended at first line (1L); the combination of gemcitabine and cisplatin (GEMCIS) was recommended as the standard of care in 1L. Recommendations for systemic chemotherapy in the second line (2L) conflicted because of uncertainties around survival benefit. Guidelines on further lines of treatment included a range of locoregional modalities and stenting or best supportive care without providing clear recommendations because of data paucity. Fifty observational studies reporting real-world treatment outcomes were extracted, of which 25 (50%) and 9 (18%) reported outcomes in 1L and 2L, respectively; 22 (44%) reported outcomes for treatments described as 'palliative'. In 1L, outcomes for systemic chemotherapy were most frequently described (23/25 studies), and GEMCIS was the most common systemic chemotherapy used (10/23 studies) in line with guidelines. Median overall survival with 1L systemic chemotherapy was < 12 months in most studies (16/23; range 4.7-22.3 months). Most 2L studies (10/11) described outcomes for systemic chemotherapy, most commonly for fluoropyrimidine-based regimen (5/10 studies). Median overall survival with 2L systemic chemotherapy was < 12 months in 5/10 studies (range 4.9-21.5 months). Median progression-free survival was reported more rarely than median overall survival. Some studies with small sample sizes or specifically selected patient populations (e.g. higher performance status, or patients who had already responded to treatment) achieved higher median overall survival.

CONCLUSIONS

At the time of this review, treatment options for unresectable advanced or metastatic biliary tract cancers confer poor real-world survival. For over a decade, GEMCIS remained the 1L standard of care, highlighting the lack of therapeutic innovation in this indication and the urgent unmet need for novel treatments with improved outcomes in this aggressive condition. Additional observational studies are needed to further understand the effectiveness of currently available treatments, as well as newly available therapies including the addition of immunotherapy in the evolving treatment landscape.

Photodynamic therapy combined with systemic chemotherapy for unresectable extrahepatic cholangiocarcinoma: A systematic review and meta-analysis

BACKGROUND

Extrahepatic cholangiocarcinoma (ECC) is a tumor with high invasiveness and poor outcome. The current treatments for unresected ECC are not ideal. Novel strategies are needed to improve the outcomes of patients with unresected ECC. Photodynamic therapy (PDT) plus chemotherapy is one of the promising interventions for ECC patients. We conducted this systematic review to determine the efficacy and safety of PDT plus chemotherapy in unresected ECC patients.

METHODS

Databases of PubMed, Cochrane Library, Embase, and Web of science were searched from inception to July 2022. Studies that compared PDT plus chemotherapy to PDT alone or chemotherapy alone in patients with unresected ECC were included. Hazard ratios (HRs) and odds ratios (ORs) with 95% confidence intervals (CIs) were pooled for overall survival (OS) and adverse events, respectively.

RESULTS

Seven eligible studies were finally included. There are four studies on PDT plus chemotherapy vs. chemotherapy alone and three studies on PDT plus chemotherapy vs. PDT alone. The meta-analysis showed that PDT plus chemotherapy had a significantly better OS than chemotherapy or PDT alone (PDT+chemotherapy vs. chemotherapy alone, HR: 0.69, p = 0.02; PDT+chemotherapy vs. PDT alone, HR:0.36, p<0.01). The occurrence of cholangitis, abscess, and photosensitivity reaction in PDT plus chemotherapy were comparable to either chemotherapy alone or PDT alone (p>0.05).

CONCLUSION

The combination of PDT and chemotherapy can improve patient survival for unresected ECC without increased adverse events. It may be a potential standard therapy in the future management of ECC.

Comparing palliative treatment options for cholangiocarcinoma: photodynamic therapy vs. radiofrequency ablation

Referral to an endoscopist is often done once curative resection is no longer an option for cholangiocarcinoma management. In such cases, palliation has become the main objective of the treatment. Photodynamic therapy and radiofrequency ablation can be performed to achieve palliation, with both procedures associated with improved stent patency and survival. Despite the greatly increased cost and association with photosensitivity, photodynamic therapy allows transmission to the entire biliary tree. In contrast, radiofrequency ablation is cheaper and faster to apply, but requires intraductal contact. This paper reviews both modalities and compares their efficacy and safety for bile duct cancer palliation.

Photodynamic Therapy (PDT), Radiofrequency Ablation (RFA) With Biliary Stents in Palliative Treatment of Unresectable Extrahepatic Cholangiocarcinoma: A Systematic Review and Meta-analysis

BACKGROUND AND AIM

Extrahepatic unresectable cholangiocarcinoma carries a dismal prognosis. In addition to biliary drainage by stent placement; photodynamic therapy (PDT) and radiofrequency ablation (RFA) have been tried to prolong survival. In this meta-analysis, we appraise the current known data on the use of PDT, RFA in the palliative treatment of extrahepatic unresectable cholangiocarcinoma.

METHODS

We searched multiple databases from inception through July 2020 to identify studies that reported on PDT and RFA. Pooled rates of survival, stent patency, 30-, 90-day mortality, and adverse events were calculated. Study heterogeneity was assessed using I2% and 95% prediction interval.

RESULTS

A total of 55 studies (2146 patients) were included. A total of 1149 patients underwent treatment with PDT (33 studies), 545 with RFA (22 studies), and 452 patients with stent-only strategy. The pooled survival rate with PDT, RFA, and stent-only groups was 11.9 [95% confidence interval (CI): 10.7-13.1] months, 8.1 (95% CI: 6.4-9.9) months, and 6.7 (95% CI: 4.9-8.4) months, respectively. The pooled time of stent patency with PDT, RFA, and stent-only groups was 6.1 (95% CI: 4.2-8) months, 5.5 (95% CI: 4.2-6.7) months, and 4.7 (95% CI: 2.6-6.7) months, respectively. The pooled rate of 30-day mortality with PDT was 3.3% (95% CI: 1.6%-6.7%), with RFA was 7% (95% CI: 4.1%-11.7%) and with stent-only was 4.9% (95% CI: 1.7%-13.1%). The pooled rate of 90-day mortality with PDT was 10.4% (95% CI: 5.4%-19.2%) and with RFA was 16.3% (95% CI: 8.7%-28.6%).

CONCLUSION

PDT seemed to demonstrate better overall survival and 30-day mortality rates than RFA and/or stent-only palliation.

WITHDRAWN: A comparative effectiveness meta-analysis of photodynamic therapy and stent drainage for unresectable cholangiocarcinoma

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Diagnosis and Management of Intrahepatic and Extrahepatic Cholangiocarcinoma

Cholangiocarcinomas (CC) are rare tumors which usually present late and are often difficult to diagnose and treat. CCs are categorized as intrahepatic, hilar, or extrahepatic. Epidemiologic studies suggest that the incidence of intrahepatic CCs may be increasing worldwide. In this chapter, we review the risk factors, clinical presentation, and management of cholangiocarcinoma.

A novel photodynamic therapy-based drug delivery system layered on a stent for treating cholangiocarcinoma

This study aimed to investigate the drug delivery efficacy and bio-effectiveness of a novel photodynamic therapy (PDT)-matrix drug delivery system for cholangiocarcinoma (CCA). Metallic stents were coated with polyurethane (PU) as the first layer. A 2-hydroxyethyl methacrylate (2-HEMA)/ethylene glycol dimethacrylate (EGDMA)/benzoyl peroxide (BPO) layer and a poly(ethylene-co-vinyl acetate) (PEVA)/poly(n-butyl methacrylate) (PBMA)/polyvinylpyrrolidone K30 (K30) layer containing various concentrations of Photofrin were then incorporated onto the stent as the second and third layers. After incubating the layered membranes with cultured CCA cell line, the release of Photofrin, cell viability, the intracellular uptake of Photofrin, reactive oxygen species (ROS) generation, and apoptosis were determined. Using a single-layer diffusion model, the maximum release of Photofrin from the 5 to 10% K30 formulas was 80 and 100%, respectively, after 24 h. When using the multiple-layer diffusion model, the released Photofrin showed an initial burst of the loading dose from the PEVA/PBMA/K30 layer. In the immobilized model, less than 5% of the Photofrin from the 2-HEMA/EGDMA/BPO layer was released over the 24-h period. Cell viability decreased linearly with increasing Photofrin concentrations, and ROS generation and apoptosis were shown to increase significantly with increasing Photofrin concentrations, until the concentration of Photofrin reached a saturation point of 1.5 μg/ml. This new, multiple-layered, PDT-based stent with dual-release mechanisms is a promising treatment for CCA and cancer-related ductal stenosis.

Photodynamic Therapy Plus Chemotherapy Compared with Photodynamic Therapy Alone in Hilar Nonresectable Cholangiocarcinoma

Background/Aims

Standard treatments are not available for hilar nonresectable cholangiocarcinoma (NCC). It is unknown whether combination therapy of photodynamic therapy (PDT) plus systemic chemotherapy is superior to PDT alone.

Methods

We retrospectively reviewed 68 patients with hilar NCC treated with either PDT plus chemotherapy (PTD-C) or PDT monotherapy (PDT-M). The primary endpoint was the mean overall survival rate. Secondary endpoints included the 1-year survival rate, risk of cholangitic complications, and outcomes, which were evaluated according to the chemotherapy protocol.

Results

More than 90% of the study population had advanced hilar NCC Bismuth type III or IV. In the PDT-M group (n=35), the mean survival time was 374 days compared with 520 days in the PDT-C group (n=33, p=0.021). The 1-year survival rate was significantly higher in the PDT-C group compared with the PDT-M group (88% vs 58%, p=0.001) with a significant reduction of mortality (hazard ratio, 0.20; 95% confidence interval, 0.07 to 0.58; p=0.003). Gemcitabine monotherapy resulted in a shorter survival time compared with the gemcitabine combination therapy (mean, 395 days vs 566 days; p=0.09). Cholangitic complications were observed at a similar frequency in the PDT-C and PDT-M groups.

Conclusions

Combining repeated PDT with a gemcitabine-based combination therapy might offer a significant survival benefit in patients with hilar NCC.

Treatment of unresectable extrahepatic cholangiocarcinoma using hematoporphyrin photodynamic therapy: A prospective study

BACKGROUND

The available evidence of Photodynamic therapy (PDT) combined with stent placement treatment for unresectable extrahepatic cholangiocarcinoma (EHCC) is still insufficient. It also remains unclear whether PDT influences systemic inflammatory response.

AIM

To explore the clinical efficacy and safety of the combination treatment and the systemic inflammatory response in patients with EHCC.

METHODS

Patients with unresectable EHCC underwent either the combined treatment using Hematoporphyrin PDT and stent placement (PDT+stent group, n=12) or stent-only (stent group, n=27). The primary end-point was overall survival. Tumor necrosis factor (TNF)-α and interleukin (IL)-6 levels were measured. Quality of life was assessed using the Karnofsky performance scale (KPS) every 3 months.

RESULTS

Average survival time (13.8 vs. 9.6 months), and 6-month (91.7% vs. 74.1%), and 1-year (58.3% vs. 3.7%) survival rates of PDT+stent group were significantly increased compared with the stent group. KPS scores in the PDT+stent group were significantly improved. TNF-α and IL-6 levels were significantly increased in the PDT+stent group.

CONCLUSION

Hematoporphyrin-PDT combined with stent placement is an effective and safe treatment for EHCC. The treatment might promote systemic inflammatory response.

Photodynamic therapy with polyhematoporphyrin for malignant biliary obstruction: A nationwide retrospective study of 150 consecutive applications

BACKGROUND

Photodynamic therapy (PDT) is a palliative treatment for malignant biliary obstruction.

OBJECTIVE

The objective of this article is to assess the feasibility and safety of this technique.

METHODS

In this nationwide, retrospective study of prospectively collected clinical data, all patients treated with PDT using polyhematoporphyrin in Austria from March 2004 to May 2013 were included. Feasibility, adverse events, stent patency and mortality rates were investigated.

RESULTS

Eighty-eight patients (54 male, 34 female, median age 69 years) underwent 150 PDT procedures at seven Austrian referral centers for biliary endoscopy. The predominant underlying disease was Klatskin tumor (79/88). All PDT procedures were feasible without technical issues. Cholangitis was the most frequent adverse event (21/88). Stent patency was 246 days (95% CI 203-289) median and was significantly longer for metal than for plastic stents (269 vs. 62 days, p < 0.01). The median survival was 12.4 months (95% CI 9.7-14.9 m) calculated from first PDT and 15.6 months (95% CI 12.3-18.7 m) calculated from initial diagnosis. In patients suffering from biliary tract cancer, Cox regression revealed the number of PDT treatment sessions as the only independent predictor of survival at a multivariate analysis (p = 0.048).

CONCLUSION

PDT using polyhematoporphyrin was feasible and safe in this nationwide analysis. Survival data suggest a benefit of PDT in this unselected real-life patient population. Prospective trials comparing PDT to other palliative treatments will help to define its role in the management of malignant biliary obstruction. The study is registered at ClinicalTrials.gov number: NCT02504957.

Efficacy and safety of photodynamic therapy for unresectable cholangiocarcinoma: A meta-analysis

BACKGROUND

Photodynamic therapy with the placement of a biliary stent may improve the prognosis in patients with unresectable cholangiocarcinoma. The aim of this research is to determine the hazard ratio of photodynamic therapy with stent compared to biliary stenting alone or other therapies for the treatment of cholangiocarcinoma.

METHODS

Several databases were searched from inception to December 31 2013 for trials comparing photodynamic therapy+stent vs. stent-only or other treatments for cholangiocarcinoma. The outcomes of interest included patient survival, the changes of serum bilirubin levels, the quality of life (Karnofsky performance status), and adverse events. The hazard ratios (HR) were extracted from the survival curves using Tierney's Method. LnHR and its variance were pooled using an inverse variance-weighted average. Inconsistency was quantified using I(2) statistics.

RESULTS

In all, 8 trials comparing PDT+stent with other therapeutic methods were selected. We made a meta-analysis based on the 7 trials, which compared the result of PDT+stent and the stent-only group. HR summarizes the survival for the two groups. Overall survival was significantly better in patients who received photodynamic therapy than those who did not [HR=0.49, 95% confidence interval (CI), 0.33∼0.73, P=0.0005]. Among the 8 trials (642 subjects), 5 assessed the changes of serum bilirubin levels, and/or Karnofsky performance status, as other indications for improvement. In all, the incidence for phototoxic reaction is 11.11%. The incidence for other events in photodynamic therapy and the stent-only group was 13.64% and 12.79%, respectively.

CONCLUSION

The palliative treatment of cholangiocarcinoma, with photodynamic therapy, is associated with an increased survival benefit, an improved biliary drainage, and a better quality of life. However, the quality of this evidence is low.

Role of photodynamic therapy and intraductal radiofrequency ablation in cholangiocarcinoma

Cholangiocarcinoma comprises 3% of all gastrointestinal malignancies. Prognosis is poor as the disease is locally advanced at the time of its presentation. Biliary endoprosthesis are widely used for biliary decompression, however, they only provides temporary relief. Photodynamic therapy and Radiofrequency ablation are two innovative approaches performed endoscopically to locally destruct the malignant tissue. This chapter focuses on their application and appropriate use along with their benefits and complications.

ERCP-directed radiofrequency ablation and photodynamic therapy are associated with comparable survival in the treatment of unresectable cholangiocarcinoma

BACKGROUND

Cholangiocarcinoma (CCA) is a malignancy with a poor 5-year survival rate (5%-10%). ERCP-directed radiofrequency ablation (RFA) or photodynamic therapy (PDT) can be performed as palliative therapy for unresectable CCA. ERCP with PDT is associated with improved survival compared with stent placement alone. However, ERCP-directed RFA has not been directly compared with PDT in patients with CCA.

OBJECTIVE

To compare overall survival in patients with unresectable CCA who underwent palliative ERCP-directed RFA versus PDT.

DESIGN

Retrospective cohort study.

SETTING

Tertiary-care academic medical center.

PATIENTS

Forty-eight patients with unresectable CCA who underwent ERCP-directed ablative therapy for palliation of unresectable CCA.

INTERVENTIONS

ERCP-directed RFA or PDT.

MAIN OUTCOME MEASUREMENTS

Overall survival by Kaplan-Meier analysis after initial treatment with either RFA or PDT.

RESULTS

Patients who underwent RFA (n = 16) demonstrated an overall survival similar to that of those who underwent PDT (n = 32), with a median survival of 9.6 versus 7.5 months, respectively (P = .799). Patient age (P = .45), sex (P = .52), and lead time (P = .59) from presentation to initial RFA or PDT had no significant association with survival. The presence of distant metastasis was inversely associated with survival (hazard ratio 3.55; 95% confidence interval, 1.29-9.77; P = .014). Patients who underwent RFA (compared with PDT) had a lower mean number of plastic stents placed per month (0.45 vs 1.10, P = .001) but also had more episodes of stent occlusion (0.06 vs 0.02, P = .008) and cholangitis (0.13 vs 0.05, P = .008) per month.

LIMITATIONS

Retrospective, single-center design.

CONCLUSIONS

Survival after ERCP-directed RFA and PDT was not statistically different in patients with unresectable CCA. A randomized, controlled trial is warranted to validate these preliminary results.

Endoscopic treatment options for cholangiocarcinomas

Cholangiocellular carcinoma (CCC) is a very aggressive tumor, which remains highly resistant to current chemoradiation therapies. Death is usually caused by the tumor burden. However, biliary obstruction, which leads to cholangitis and liver failure, is also a cause of death. Therefore, relief of biliary obstruction is one of the key palliative treatment options for patients with hilar or distal CCC. Radiologic or endoscopic insertions of stents (plastic or self-expanding metal) are definite biliary drainage options. Whereas stents alone can help achieve relief of bile duct obstruction, endoscopic ablative interventions with photodynamic therapy or radiofrequency ablation are also useful in destroying intraluminal tumor. Destroying the tumor leads to an increase in the luminal diameter of the obstructed bile duct, allowing for placement of more or larger diameter stents, and thus improving bile flow. Besides decreasing morbidity associated with obstruction, ablative therapies such as photodynamic therapy have also been associated with improved survival in a sub-group of patients with CCC and should therefore be incorporated into the treatment algorithm of any center treating patients with CCC.

Photodynamic therapy provides local control of cholangiocarcinoma in patients awaiting liver transplantation

Many transplant centers use endoscopically directed brachytherapy to provide locoregional control in patients with otherwise incurable cholangiocarcinoma (CCA) who are awaiting liver transplantation (LT). The use of endoscopic retrograde cholangiopancreatography (ERCP)-directed photodynamic therapy (PDT) as an alternative to brachytherapy for providing locoregional control in this patient population has not been studied. The aim of this study was to report on our initial experience using ERCP-directed PDT to provide local control in patients with unresectable CCA who were awaiting LT. Patients with unresectable CCA who underwent protocol-driven neoadjuvant chemoradiation and ERCP-directed PDT with the intent of undergoing LT were reviewed. Four patients with confirmed or suspected CCA met the inclusion criteria for protocol LT. All four patients (100%) successfully underwent ERCP-directed PDT. All patients had chemoradiation dose delays, and two patients had recurrent cholangitis despite PDT. None of these patients had progressive locoregional disease or distant metastasis following PDT. All four patients (100%) underwent LT. Intention-to-treat disease-free survival was 75% at mean follow-up of 28.1 months. In summary, ERCP-directed PDT is a reasonably well tolerated and safe procedure that may have benefit by maintaining locoregional tumor control in patients with CCA who are awaiting LT.

Preliminary safety evaluation of photodynamic therapy for blood purification: an animal study

Photodynamic therapy (PDT) has been shown to inactivate blood-borne pathogenic microorganisms in vitro. The method may be used to purify blood in the body, kill pathogenic microorganisms, and treat difficult diseases. Our aim was to investigate the safety of photodynamic blood purification (PBP) therapy using an in vivo blood circulation experiment in an animal model. Twenty-four New Zealand rabbits were used as experimental subjects; 12 received PDT and 12 served as negative controls. Extracorporeal blood bypass was established using the femoral artery and vein. A sterile disposable irradiation chamber was connected in the bypass pathway. Hematoporphyrin monomethyl ether was injected intravenously as a photosensitizer with an initial bolus of 3.7 mg, followed by a continuous infusion at 24 mg/h during PDT administration. Five minutes after initial injection, a laser beam was vertically focused on the irradiation chamber side wall, with a 9.5 cm(2) spot area, 1 h exposure time, and 20 mW/cm(2) power density. Six animals received a single PDT application, and six received PDT every other day for three applications. The 12 control group animals underwent extracorporeal blood circulation but did not receive the photosensitizer or light treatment. Blood samples were taken 20 min, 1 day, 4 days, and 7 days after PDT treatment for analysis of cell counts, coagulation, liver and renal function, and other biochemical changes. On the 7th day, animals were sacrificed, and parenchymal organs were evaluated for morphological changes. There were no significant differences in white blood cells, red blood cells, or destroyingplatelets after PDT compared with the control group. There was a little significant difference in alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, γ-glutamyl transpeptidase, uric acid, blood urea nitrogen, and creatinine in the PDT group compared with the control group, except at individual time points. We found no significant damage in the heart, liver, spleen, lungs, kidneys, or other organs after PDT. This short-duration, fixed-strength PBP method did not cause changes in blood parameters or in the structure or function of major organs in an animal model. These findings suggest that PBP is safe in vivo and has potential as a new therapy for inactivating blood-borne microorganisms.

Photodynamic therapy for unresectable cholangiocarcinoma: a comparative effectiveness systematic review and meta-analyses

BACKGROUND

Photodynamic therapy (PDT) with placement of a biliary stent may improve bile duct patency in patients with cholangiocarcinoma (CCA). We aimed to determine the effectiveness of biliary stenting with PDT compared to biliary stenting alone in the palliative treatment of CCA.

MATERIALS AND METHODS

Several databases were searched from inception to December 2011 for prospective studies comparing biliary stenting with PDT vs. biliary stenting only for CCA. Outcomes of interest included patient survival, quality of life (using Karnofsky score), and serum bilirubin levels. The relative risk (RR) for dichotomous outcomes and the weighted mean difference (WMD) for continuous outcomes were estimated using DerSimonian and Laird random-effects model. Inconsistency was quantified using I(2) statistics. The extent of publication bias was ascertained by visual inspection of funnel plots and Egger's test.

RESULTS

There were six studies that met inclusion criteria. A total of 170 participants received PDT and 157 had biliary stenting only. Compared with biliary stenting, PDT was associated with a statistically significant increase in the length of survival (WMD 265 days; 95% CI: 154-376; p = 0.01; I(2) = 65%), improvement in Karnofsky scores (WMD 7.74; 95% CI: 3.73-11.76; p = 0.01; I(2)= 14%), and a trend for decline in serum bilirubin (WMD -2.92 mg/dL; 95% CI: -7.54 to 1.71; p=0.22; I(2) = 94%). The pooled event rate for biliary sepsis was 15% and was similar between PDT and control groups.

CONCLUSION

Palliative treatment of CCA with PDT is associated with increased survival benefit, improved biliary drainage, and quality of life. However, the quality of this evidence is low.