Clinical impact and potential utility of non-enhanced computed tomography performed immediately after transarterial chemoembolization for hepatocellular carcinoma.

Background: Intratumoral lipiodol deposition following transarterial chemoembolization (TACE) is associated with the prognosis of hepatocellular carcinoma (HCC) patients. However, there is insufficient evidence regarding the actual clinical significance of the imaging tests conducted to evaluate the lipiodol uptake after TACE. This study evaluates the clinical impact and potential utility of performing immediate post-TACE non-enhanced computed tomography (NECT) on the treatment of HCC. Methods: This retrospective study at a tertiary referral center included patients undergoing their first session of conventional TACE for initial treatment of HCC from November 2021 to December 2022 with available immediate post-TACE NECT. Patients were categorized based on lipiodol uptake into Cohorts A (incomplete uptake with additional treatment before the first follow-up 1 month after TACE), B incomplete uptake without additional treatment before first follow-up), and C (complete uptake). Survival curves for the time to progression (TTP) were estimated using the Kaplan-Meier method and were compared by using the log-rank test. Results: Out of 189 patients, 58 (29.6%) showed incomplete lipiodol uptake; 2 in Cohort A and 56 in Cohort B. Cohort C included 131 patients (69.3%). Cohort B had the highest rate of residual viable tumor (48.2%) 1 month after TACE, compared to the other cohorts (0% in Cohort A and 32.1% in Cohort C). The median TTP of Cohort B was 7.9 months [95% confidence interval (CI): 4.6-15.7 months], significantly shorter than the 15.4 months (95% CI: 10.9-20.9 months) for Cohort C (P=0.03). During follow-up, no progression occurred in Cohort A. Conclusions: Assessment of lipiodol uptake by performing immediate post-TACE NECT can stratify HCC patients and facilitate early prediction of therapeutic response. Identifying suboptimal lipiodol uptake immediately after TACE can aid future treatment adjustments and potentially improving oncologic outcomes.

Foreign Body Granuloma After Embolization of Internal Iliac Artery Aneurysm Using N-Butyl-2-Cyanoacrylate: A Case Report.

Foreign body granulomas following endovascular treatment are rare complications and are mostly reported in the brain or cutaneous vascular tissues. To the best of our knowledge, no study to date has reported on foreign body granulomas in the abdomen after injection of N-butyl-2-cyanoacrylate (NBCA)-lipiodol mixture into the abdominal arteries. This study reports a case of foreign body granuloma that appeared 12 months after the embolization of a right internal iliac artery aneurysm using an NBCA-lipiodol mixture, which posed challenges in differentiation from malignant tumors. We present a 77-year-old man who underwent embolization of a right internal iliac artery aneurysm and open surgical repair of an abdominal aortic aneurysm. A contrast-enhanced CT performed 12 months postoperatively revealed a right-sided retroperitoneal mass surrounding the iliopsoas muscle. The mass contained multiple, small, hyperdense areas, suggesting the migration of the NBCA-lipiodol mixture casts from the embolized right internal iliac artery aneurysm. The differential diagnosis included foreign body granuloma, lymphoma, and sarcoma. A biopsy of the lesion revealed a granuloma with various stages of inflammation, no hemosiderin deposition, multinucleated giant cells, and foam cells containing fat, and was diagnosed with a foreign body granuloma. Special staining for microorganisms revealed no findings suggestive of infection. Because the patient was asymptomatic, no treatment was administered. Contrast-enhanced CT at 24 months postoperatively showed shrinkage of the mass, with no change in size noted at 48 months postoperatively. This report highlights a foreign body granuloma that mimicked malignant tumors. Extravascular migration of the NBCA-lipiodol mixture casts likely contributed to granuloma formation. Radiologists should consider foreign body granulomas after embolization using NBCA into the abdominal arteries.

Lipiodol combined with drug-eluting beads versus drug-eluting beads alone for transarterial chemoembolization of hepatocellular carcinoma: a multicenter study.

RATIONALE AND OBJECTIVES: This study aimed to propose a novel approach of lipiodol combined with drug-eluting beads transarterial chemoembolization (Lipiodol-DEB TACE) and to compare the safety and efficacy with DEB-TACE alone for patients with unresectable hepatocellular carcinoma (HCC). MATERIALS AND METHODS: From the database of four centers, the records of patients with HCC who received DEB-TACE or Lipiodol-DEB TACE as initial treatment were retrospectively evaluated. The tumor response was measured based on the Modified Response Evaluation Criteria in Solid Tumors. Overall survival (OS), progression-free survival (PFS) and adverse events (AEs) were compared between two groups. RESULTS: A total of 244 patients were included with 160 patients receiving DEB-TACE and 84 patients receiving Lipiodol-DEB TACE. Lipiodol-DEB TACE group had higher objective response rate (86.9 % vs. 76.3 %), higher disease control rate (97.6 % vs. 88.8 %), longer median OS (42.6 vs. 25.8 months) and longer median PFS (34.0 vs. 17.0 months) than DEB-TACE group (P < 0.05). There was no significant difference observed in the incidence of AEs between two groups. Cox analysis identified total bilirubin level, maximum tumor diameter, TACE method and portal vein invasion as independent prognostic factors. CONCLUSION: Lipiodol-DEB TACE was a safe option and associated with improved tumor response and survival outcome compared to DEB-TACE alone for selected patients with HCC.

Transcatheter arterial perfusion chemotherapy combined with lipiodol chemoembolization for advanced colorectal cancer complicated by obstruction.

Background: Obstruction is a common complication of advanced colorectal cancer. This study was aimed at investigating the safety, efficacy, and feasibility of transcatheter arterial perfusion chemotherapy combined with lipiodol chemoembolization for treating advanced colorectal cancer complicated by obstruction. Patients and methods: This retrospective analysis was conducted using clinical data of patients with advanced colorectal cancer who received arterial infusion chemotherapy combined with lipiodol chemoembolization treatment at our center. Treatment efficacy was evaluated in terms of obstruction-free survival and overall survival, and treatment complications were monitored. Results: Fifty-four patients with colorectal cancer complicated by obstruction were included. All patients successfully underwent transcatheter arterial infusion combined with lipiodol chemoembolization treatment. The average lipiodol dose administered was 2.62 ± 1.45 ml (0.5-5.5 ml). No serious complications such as perforation or tumor dissemination occurred. The clinical success rate was 83.3% (45/54). One month after treatment, the objective response rate (ORR) and disease control rate (DCR) were 66.67% and 88.9%, respectively. The median obstruction-free survival was 5.0 months. No serious adverse events occurred. As of the last follow-up, 6 patients survived, 44 died, and 4 were lost to follow-up. Conclusion: Our findings revealed that transcatheter arterial infusion chemotherapy combined with lipiodol chemoembolization is safe and effective for treating advanced colorectal cancer complicated by obstruction. It may serve as a new treatment strategy for patients with advanced colorectal cancer complicated by obstruction.

Effect of iodized oil embolization on temperature change during cryoablation for renal cell carcinoma.

INTRODUCTION: We aimed to evaluate the effect of transcatheter arterial embolization (TAE) with iodized oil (Lipiodol) on temperature change during cryoablation (CA) for renal cell carcinoma (RCC). MATERIAL AND METHODS: We retrospectively reviewed patients receiving CA for RCC from February 2020 to July 2021, including those who received Lipiodol TAE prior to CA (TAE group) and those who underwent only CA with comparable clinical and tumor characteristics (non-TAE group). Clinical data and tumor characteristics of both groups were recorded. The temperature readings of each cryoprobe at every 15 s and 'time to -100 °C' were compared between the groups. RESULTS: A total of 17 patients with 18 RCCs were recruited (seven in the TAE group and 11 in the non-TAE group). The 'time to -100 °C' was significantly longer in the TAE group than in the non-TAE group (64.5 ± 24.3 s vs. 48.8 ± 9.7 s, p = 0.018). Positive correlation between 'time to -100 °C' and tumor maximal diameter, RENAL nephrometry and PADUA score were observed in the non-TAE group, while no corresponding correlation was found in the TAE group. CONCLUSIONS: Pre-embolization with iodized oil influences the temporal temperature changes during cryoablation by disrupting the positive correlation between the time to reach the target temperature and tumor characteristics.

Ultrasound-guided Lipiodol® hysterosalpingography: A prospective study on pregnancy and complication rates.

BACKGROUND: Fluoroscopic hysterosalpingography (HSG) with Lipiodol® is safe and has a therapeutic effect on fertility: transient in endometriosis-related infertility and sustained in unexplained infertility. Ultrasound is replacing fluoroscopy as the preferred imaging modality for HSG due to comfort and radiation safety (no ionising radiation). The safety of ultrasound-guided Lipiodol® HSG is uncertain. AIMS: Prospectively observe pregnancy and complication rates after ultrasound-guided Lipiodol® HSG. MATERIALS AND METHODS: A single-centre prospective study of women with unexplained infertility undergoing ultrasound-guided Lipiodol® uterine bathing and tubal flushing after tubal patency confirmed with ExEm® Foam HyFoSy (hysterosalpingo-foam-sonography). Pregnancy outcomes at six months and serum and urinary thyroid function at one, three and eight weeks were recorded. Pain scores were recorded during and immediately after HSG. Descriptive statistics are reported. RESULTS: Fifty-two participants were enrolled between July 2019 and April 2021, median age 33 years (range 21-45). Only 45 (87%, 45/52) completed the Lipiodol® HSG; 5/7 experienced intravasation during initial HyFoSy. Of 30 women at follow-up, 57% had biochemical (17/30, 95% CI 37%-75%), 53% clinical (16/30 95% CI 34%-72%) and 35% ongoing pregnancies (11/30, 95% CI 20%-56%). The rate of subclinical hypothyroidism (SCH) at two months was 41% (7/17). One intravasation event occurred during Lipiodol® HSG (2%, 1/45). Median pain score was 5/10 (range 0-9, interquartile range 2.5-7). No anaphylaxis, infection or oil embolism was observed. CONCLUSION: Outpatient ultrasound-guided Lipiodol® HSG was safe, with pregnancy rates comparable to previous studies of fluoroscopic guidance. Rates of intravasation and SCH were also similar, confirming the need to monitor thyroid function.

A case of chylous ascites caused by reflux from the cisterna chyli to the disrupted common iliac lymphatic vessel: fluoroscopic records during intranodal lymphangiography.

A 40-year-old woman underwent laparoscopic common iliac lymphadenectomy for metastasis from rectal cancer. Two weeks after the surgery, she was found to have massive chylous ascites. After failure of conservative treatment, bilateral inguinal intranodal lymphangiography was performed. No definite extravasation was observed while lipiodol injected through the left inguinal node was ascending. When we punctured the right inguinal lymph nodes and started the injection of lipiodol, extravasation of diluted lipiodol was noted at the level of the first sacrum. Careful observation revealed that the ascending lipiodol became diluted in the cisterna chyli, refluxed through the median paraaortic route, leaked from the excised left common iliac lymph vessel, and flowed into the abdominal cavity. Lipiodol used in lymphangiography did not reduce chylous ascites at all. Twenty-seven days after lymphangiography, laparoscopic lymphatic ligation was performed, and the chylous ascites disappeared completely. CT obtained 40 days after surgical repair revealed disappearance of ascites and enlargement of the thoracic duct, which had not been observed on preoperative lymphangiography. Notably, lymphatic reflux from the cisterna chili can occur without obstruction of the thoracic duct and may result in chylous ascites.

Treatment Of Post-Operative Chylothorax: The Role Of Intranodal Lymphangiography And Thoracic Duct Disruption.

Thoracic duct embolization has been increasingly adopted as a first-line therapy of chylothorax and this procedure includes lipiodol lymphangiography, thoracic duct access and embolization. Lymphangiography itself has a therapeutic role, with volume-dependent success rates of 37%-97% and even a reported 100% success rate in outputs of < 500 mL/day. We present a clinical case of a 48-years-old man diagnosed with esophageal squamous cell carcinoma, who underwent esophagectomy and presented with post-operative high-output (> 1L/day) chylothorax; thoracic duct embolization was proposed. Even though thoracic duct access and embolization were not achieved due to technical and anatomical factors, lipiodol lymphangiography and possibly thoracic duct maceration (after several punctures/attempts) contributed to the clinical success of the procedure, and this chylothorax with output values superior to those reported in the literature resolved within three days. As such, the therapeutic role of intranodal lymphangiography and thoracic duct disruption should be taken into account.

Lipiodol embolization for chylous leak complication post robotic-assisted para-aortic lymph node resection.

Thoracic or abdominal chylous leakage, a rare complication of lymph node removal procedures, can lead to the accumulation of lymph fluid within the abdominal cavity, resulting in chylous ascites, abdominal distension, discomfort, and an increased risk of infection. Lipiodol lymphangiography, a diagnostic procedure utilizing a unique contrast agent, serves to identify the site and cause of chylous leaks. Furthermore, it functions as a therapeutic tool by injecting Lipiodol into the affected lymphatic vessel. By employing this diagnostic procedure, successful closure of the leak can be achieved. We present a case where a chylous leak was effectively treated with Lipiodol injection following the robotic-assisted removal of metastatic lymph nodes surgery.

Transarterial Bleomycin-Lipiodol Chemoembolization for the Treatment of Giant Hepatic Hemangiomas: An Assessment of Effectiveness.

This study evaluates the effectiveness of superselective transcatheter arterial chemoembolization (TACE) using a bleomycin-lipiodol emulsion in treating giant hepatic hemangiomas. A retrospective review included 31 patients with a mean age of 53 ± 10.42 years who underwent TACE from December 2014 to October 2022, with follow-up imaging examinations to assess outcomes. Technical success was defined as successful embolization of all feeding arteries, and clinical success was defined as a reduction in hemangioma volume by 50% or more on follow-up imaging. This study observed a 100% technical success rate. Post-embolization syndrome was common, and two cases of asymptomatic hepatic artery dissection were noted. Clinical success was achieved in 80.6% of patients, with significant volume reduction observed in the majority. Conclusively, superselective transcatheter arterial chemoembolization with bleomycin-lipiodol emulsions is presented as a viable and effective treatment option for giant hepatic hemangiomas. With no procedure-related mortality and significant volume reduction in most cases, this method offers a promising alternative to surgical intervention. This study's findings suggest a need for further exploration and validation in larger-scale prospective studies.

The impact of lymphangiograpy on chyle leakage treatment duration after pancreatic surgery.

PURPOSE: Chyle leakage (CL) is a common complication in pancreatic surgery. Lymphangiography is a therapeutic option for CL in cases of conservative treatment failure. This study investigated the effect of lymphangiography on the healing time of CL. METHODS: We retrospectively evaluated 283 patients who underwent pancreatic resection between January 2016 and June 2022. The risk factors for CL and the treatment period were evaluated according to whether or not lymphangiography was performed. RESULTS: Of the 29 patients (10.2%) that had CL, lymphangiography was performed in 6. Malignant disease, the number of harvested lymph nodes, and drain fluid volume on postoperative day 2 were identified as independent risk factors for CL. Lymphangiography was associated with the cumulative healing rate of CL, and patients who underwent lymphangiography had a significantly shorter treatment period. No lymphangiography-related adverse events were observed. CONCLUSION: Lymphangiography is a feasible and safe treatment option for CL. The CL treatment period after pancreatic surgery was significantly shorter in patients who underwent lymphangiography than in those who did not. Our results suggest that lymphangiography may contribute to early improvement of persistent CL.

Iodixanol as a New Contrast Agent for Cyanoacrylate Embolization: A Preliminary In Vivo Swine Study.

N-butyl cyanoacrylate (NBCA) is a lipophilic, permanent embolic glue that must be opacified for fluoroscopic guidance. Empirically, lipophilic Lipiodol Ultra Fluid® (LUF) has been added to produce a single-phase physically stable mixture. Varying the dilution ratio allows control of glue polymerization kinetics. LUF is far more costly than water-soluble iodinated contrast agents (ICAs). Our purpose was to evaluate whether a water-soluble nonionic iso-osmolar ICA could be used instead. We embolized both renal arteries of six swine using 1:3 NBCA-LUF or NBCA-iodixanol in 1:1, 1:3, and 1:7 ratios. We used both micro-computed tomography to assess the distality of glue penetration and indexed cast ratio and histology to assess distality, arterial obliteration, vessel-wall damage, and renal-parenchyma necrosis. Glue-LUF produced significantly greater indexed cast ratio and renal-artery ROI values and a significantly shorter cast-to-capsule distance. The injected volume was significantly greater with 1:7 iodixanol than with the other mixtures. No significant differences were found for histological evidence of artery obliteration, vessel-wall damage, or renal-parenchyma necrosis. This is the first study dealing with ICA alone as a contrast agent for cyanoacrylate embolization, compared to LUF. More research is needed to determine whether water-soluble nonionic iodinated agents can be used for human NBCA embolization given the good safety profile, availability, and low cost of ICA.

Degradable Starch Microspheres Transarterial Chemoembolization with or without Lipiodol for Liver Metastases from Pancreatic Cancer: A Prospective Randomized Trial.

To evaluate and compare the outcome of patients with liver metastases from pancreatic cancer treated by transarterial chemoembolization (TACE) using two different protocols. In this prospective, randomized, single-center trial, patients were randomly assigned to receive TACE therapy either with degradable starch microspheres (DSM) alone or a combination of Lipiodol and DSM. From the initial 58 patients, 26 patients (13 DSM-TACE, 13 Lipiodol + DSM-TACE) who completed 3 TACE treatments at an interval of four weeks were considered for evaluation of tumor responses. Initial and final MRIs were used to evaluate local therapy response by RECIST 1.1; changes in diameter, volume, ADC value, and survival rate were statistically evaluated. The differences between the DSM-TACE and Lipiodol + DSM-TACE were identified for partial response (PR) as 15.4% versus 53.8%, stable disease (SD) as 69.2% versus 46.2%, progressive disease (PD) as 15.4% versus 0%, respectively (p = 0.068). Median overall survival times for DSM-TACE and Lipiodol + DSM-TACE were 20 months (95% CI, 18.1-21.9) and 23 months (95% CI, 13.8-32.2), respectively (p = 0.565). The one-year survival rates for DSM-TACE and Lipiodol + DSM-TACE were 85.4% and 60.4%, the two-year survival rates were 35.9% and 47.7%, and the three-year survival rates were 12% and 30.9%, respectively. The evaluated local therapy response by RECIST 1. was not significantly different between the two studied groups. A longer overall survival time was observed after Lipiodol + DSM-TACE therapy; however, it was not significantly different.

Biological efficacy of simulated radiolabeled Lipiodol® ultra-fluid and microspheres for various beta emitters: study based on VX2 tumors.

BACKGROUND: Radioembolization is one therapeutic option for the treatment of locally early-stage hepatocellular carcinoma. The aim of this study was to evaluate the distribution of Lipiodol® ultra-fluid and microspheres and to simulate their effectiveness with different beta emitters (90Y, 188Re, 32P, 166Ho, 131I, and 177Lu) on VX2 tumors implanted in the liver of 30 New Zealand rabbits. RESULTS: Twenty-three out of 30 rabbits had exploitable data: 14 in the group that received Lipiodol® ultra-fluid (group L), 6 in the group that received microspheres (group M), and 3 in the control group (group C). The histologic analysis showed that the Lipiodol® ultra-fluid distributes homogeneously in the tumor up to 12 days after injection. The X-ray µCT images showed that Lipiodol® ultra-fluid has a more distal penetration in the tumor than microspheres. The entropy (disorder of the system) in the L group was significantly higher than in the M group (4.06 vs 2.67, p = 0.01). Equivalent uniform biological effective doses (EUBED) for a tumor-absorbed dose of 100 Gy were greater in the L group but without statistical significance except for 177Lu (p = 0.03). The radionuclides ranking by EUBED (from high to low) was 90Y, 188Re, 32P, 166Ho, 131I, and 177Lu. CONCLUSIONS: This study showed a higher ability of Lipiodol® ultra-fluid to penetrate the tumor that translated into a higher EUBED. This study confirms 90Y as a good candidate for radioembolization, although 32P, 166Ho, and 188Re can achieve similar results.

Explosomes: A new modality for DEB-TACE local delivery of sorafenib: In vivo proof of sustained release.

The current medical practice in treating Hepatocellular carcinoma (HCC) using Drug Eluting Transarterial chemoembolization (DEB-TACE) technique is limited only to hydrophilic ionizable drugs, that can be attached ionically to the oppositely charged beads. This limitation has forced physicians to subscribe the more hydrophobic, first treatment option drugs, like sorafenib systemically via the oral route, thus flooding the patient system with a very powerful, non-specific, multiple-receptor tyrosine kinase inhibitor that is associated with notorious side effects. In this paper, a new modality is introduced, where highly charged, drug loaded liposomes are added to oppositely charged DEBs in a manner causing them to "explode" and the drug is eventually attached to the beads in the lipid patches covering their surfaces; therefore we call them "Explosomes". After fully describing the preparation process and in vitro characterization, this manuscript delves into an in vivo pharmacokinetic study over 50 New Zealand rabbits, where explosomal loading is challenged vs oral as well as current practice of emulsifying sorafenib in lipiodol. Over 14 days of follow up, and compared to other groups, explosomal loading of SRF on embolic beads proved to cause a slower release pattern with longer Tmax, lower Cmax and less washout to general circulation in healthy animals. This treatment modality opens a new untapped door for local sustained delivery of hydrophobic drugs in catheterized organs.

What are the risks associated with lipiodol hysterosalpingography? A literature review.

INTRODUCTION: Hysterosalpingography is widely used as a first-line investigation for infertility, and may also be therapeutic, increasing pregnancy rates. Aqueous and oil-based contrast agents can be used. Some studies suggest Lipiodol hysterosalpingography has a greater therapeutic effect on fertility than aqueous contrast, though this is contentious. There are additionally safety concerns surrounding Lipiodol hysterosalpingography. This review summarises the adverse effects associated with Lipiodol hysterosalpingography, particularly on thyroid function. KEY FINDINGS: 331 articles were identified. Of these, 46 met inclusion criteria. 3 further articles were identified from reference lists. Complications typically cited in the literature include pain, intravasation, life-threatening oil embolism, and lipogranuloma formation. Emerging evidence suggests that Lipiodol hysterosalpingography may also impact maternal and neonatal thyroid function. Women may develop hypo- or hyperthyroidism. Thyroid dysfunction is clinically significant as even subclinical hypothyroidism reduces fertility, increases the risk of pregnancy complications including miscarriage, pre-eclampsia and perinatal mortality, and adversely impacts foetal neurodevelopment. One study suggested a possible link with neonatal congenital hypothyroidism. CONCLUSION: There is emerging evidence to suggest that Lipiodol hysterosalpingography can cause hypo- or hyperthyroidism, in addition to known adverse effects of pain, intravasation, oil embolism, and lipogranuloma formation. IMPLICATIONS FOR PRACTICE: Given the significance of these risks, and contention surrounding whether Lipiodol truly increases pregnancy rates compared to aqueous mediums, careful consideration is required in the selection of contrast agent. In particular, Lipiodol hysterosalpingography may not be suitable for women with pre-existing thyroid dysfunction.

Preoperative transarterial chemoembolization (TACE) + liver resection versus upfront liver resection for large hepatocellular carcinoma (≥5 cm): a systematic review and meta-analysis.

BACKGROUND: Hepatocellular carcinoma (HCC) accounts for majority of primary liver cancer. Use of preoperative neoadjuvant transarterial chemoembolization (PN-TACE) may result in tumor shrinkage and improve resectability. This study aims to summarize the outcomes of PN-TACE versus upfront liver resection (Up-LR) in large HCC (≥5 cm). METHODS: PubMed, Embase, The Cochrane Library, and Scopus were systematically searched till September 2022 for studies comparing PN-TACE versus Up-LR. The primary study outcomes were overall survival (OS), disease-free survival (DFS), and recurrence. Our secondary outcomes were postoperative morbidity and mortality. RESULTS: There were 12 studies with 15 data sets including 3960 patients (PN-TACE n = 2447, Up-LR n = 1513). Majority (89.5%, n = 1250/1397) of patients had Child's A liver cirrhosis. Incidence of Child's B cirrhosis was higher in PN-TACE compared to Up-LR (Odds ratio (OR) 1.69, 95% CI: 1.18, 2.41, p = 0.004). Pooled hazard ratio (HR) for OS showed no significant difference between PN-TACE and Up-LR (HR 0.87, 95% CI: 0.64, 1.18, p = 0.37), but DFS was superior in PN-TACE (HR 0.79, 95% CI: 0.63, 0.99, p = 0.04). Subgroup analysis based on study design failed to show any significant effect in randomized controlled trials (n = 2/15 data sets). However, operating time (mean difference (MD) 31.94 min, 95% CI: 2.42, 61.45, p = 0.03) and blood loss (MD 190.93 ml, 95% CI: 10.22, 317.65, p = 0.04) were higher in PN-TACE. Intrahepatic and extrahepatic recurrence, post-operative morbidity and in-hospital mortality were comparable between PN-TACE and Up-LR. CONCLUSION: In retrospective studies, PN-TACE resulted in superior DFS compared to Up-LR. However, this may be confounded by selection bias.

Clinical and dosimetric outcomes of image-guided, dose-painted radiotherapy in muscle invasive bladder cancer.

PURPOSE/OBJECTIVE: Definitive radiotherapy (RT) is an alternative to radical cystectomy for select patients with muscle invasive bladder cancer (MIBC); however, there is limited data on dose-painted RT approaches. We report the clinical and dosimetric outcomes of a cohort of MIBC patients treated with dose-painted RT. MATERIAL/METHODS: This was a single institution retrospective study of cT2-4N0M0 MIBC patients treated with external beam radiotherapy (EBRT) to the bladder, and sequential or concomitant boost to the tumor bed. The target delineation was guided by either intravesical injection of Lipiodol or through fusion of the pre-treatment imaging. The majority were treated with daily image-guidance. Kaplan-Meier was used to characterize overall survival (OS) and progression-free survival (PFS). Cumulative incidence function (CIF) was used to estimate local (intravesical) recurrence (LR), regional recurrence (RR) and distant metastasis (DM). Univariable and multivariable cause-specific hazard model was used to assess factors associated with LR and OS. RESULTS: 117 patients were analyzed. The median age was 73 years (range 43, 95). The median EQD2 to the boost volume was 66 Gy (range 52.1, 70). Lipiodol injection was used in 64 patients (55%), all treated with IMRT/VMAT. 95 (81%) received concurrent chemotherapy, of whom, 44 (38%) received neoadjuvant chemotherapy. The median follow-up was 37 months (IQR 16.2, 83.3). At 5-year, OS and PFS were 79% (95% CI 70.5-89.2) and 46% (95% CI 36.5-57.5). Forty-five patients had bladder relapse, of which 30 patients (67%) were at site of the tumor bed. Nine patients underwent salvage-cystectomy. Late high-grade (G3-G4) genitourinary and gastrointestinal toxicity were 3% and 1%. CONCLUSION: Partial boost RT in MIBC is associated with good local disease control and high rates of cystectomy free survival. We observed a pattern of predominantly LR in the tumor bed, supporting the use of a dose-painted approach/de-escalation strategy to the uninvolved bladder. Prospective trials are required to compare oncological and toxicity outcomes between dose-painted and homogeneous bladder RT techniques.