Variation in Androgen Deprivation Therapy Use Among Men with Intermediate Risk Prostate Cancer: Results from a Statewide Radiation Oncology Quality Consortium.

PURPOSE: For men with intermediate risk prostate cancer treated with definitive therapy, the addition of androgen deprivation therapy (ADT) reduces the risk of distant metastasis and cancer-related mortality. However, the absolute benefit of ADT varies by baseline cancer risk. Estimates of prognosis have improved over time, and little is known about ADT decision making in the modern era. We sought to characterize variability and identify factors associated with intended ADT use within the [statewide quality consortium]. MATERIALS AND METHODS: Patients with localized prostate cancer undergoing definitive radiotherapy were enrolled from 6/9/20 to 6/26/23 (n=815). Prospective data was collected using standardized patient, physician, and physicist forms. Intended ADT use was prospectively defined and is the primary outcome. Associations with patient, tumor, and practice-related factors were tested with multivariable analyses (MVA). Random intercept modeling was used to estimate facility-level variability. RESULTS: Five-hundred seventy patients across 26 facilities were enrolled with intermediate risk disease. ADT was intended for 46% of men (n=262/570), which differed by NCCN favorable intermediate-risk (FIR) (23.5%, n=38/172) vs unfavorable intermediate-risk (UIR) disease (56.3%, n=224/398), p<0.001. After adjusting for the statewide case mix, the predicted probability of intended ADT use varied significantly across facilities, ranging from 15.4% (95% CI 5.4-37.0%) to 71.7% (95% CI 57.0-82.9%), p<0.01. MVA showed that grade group 3 (OR 4.60 [3.20-6.67]), ≥50% positive cores (OR 2.15 [1.43-3.25]), and PSA 10-20 (OR 1.87 [1.24-2.84]) were associated with ADT use. AUC was improved when incorporating MRI adverse features (0.76) or radiation treatment variables (0.76), but there remained significant facility level heterogeneity in all models evaluated (p<0.05). CONCLUSIONS: Within a state-wide consortium, there is substantial facility-level heterogeneity in intended ADT use for men with intermediate risk prostate cancer. Future efforts are necessary to identify patients who will benefit most from ADT and to develop strategies to standardize appropriate use.

Sensitivity of the Boston criteria version 2.0 in Dutch-type hereditary cerebral amyloid angiopathy.

BACKGROUND AND AIM: The revised Boston criteria v2.0 for cerebral amyloid angiopathy (CAA) add two radiological markers to the existing criteria: severe visible perivascular spaces in the centrum semiovale and white matter hyperintensities (WMHs) in a multispot pattern. This study aims to determine the sensitivity of the updated criteria in mutation carriers with Dutch-type hereditary CAA (D-CAA) in an early and later disease stage. METHODS: In this cross-sectional study, we included presymptomatic and symptomatic D-CAA mutation carriers from our prospective natural history study (AURORA) at the Leiden University Medical Center between 2018 and 2021. 3-Tesla scans were assessed for CAA-related magnetic resonance imaging (MRI) markers. We compared the sensitivity of the Boston criteria v2.0 to the previously used modified Boston criteria v1.5. RESULTS: We included 64 D-CAA mutation carriers (mean age 49 years, 55% women, 55% presymptomatic). At least one white matter (WM) feature was seen in 55/64 mutation carriers (86%: 74% presymptomatic, 100% symptomatic). Fifteen (23%) mutation carriers, all presymptomatic, showed only WM features and no hemorrhagic markers. The sensitivity for probable CAA was similar between the new and the previous criteria: 11/35 (31%) in presymptomatic mutation carriers and 29/29 (100%) in symptomatic mutation carriers. The sensitivity for possible CAA in presymptomatic mutation carriers increased from 0/35 (0%) to 15/35 (43%) with the new criteria. CONCLUSION: The Boston criteria v2.0 increase the sensitivity for detecting possible CAA in presymptomatic D-CAA mutation carriers and, therefore, improve the detection of the early phase of CAA.

Diffusion MRI correlation with p16 status and prediction for tumor progression in locally advanced head and neck cancer.

Purpose: To investigate p16 effects on diffusion image metrics and associations with tumor progression in patients with locally advanced head and neck cancers. Methods: Diffusion images pretreatment and after 20 Gy (2wk) of RT were analyzed in patients with cT4/N3 p16+ oropharynx cancer (OPSCC) (N=51) and locoregionally advanced head and neck squamous cell carcinoma (LAHNSCC) (N=28), enrolled onto a prospective adaptive RT trial. Mean ADC values, subvolumes with ADC <1.2 um2/ms (TVLADC), and peak values of low (µL) and high (µH) components of ADC histograms in primary and total nodal gross tumor volumes were analyzed for prediction of freedom from local, distant, or any progression (FFLP, FFDP or FFLRDP) using multivariate Cox proportional-hazards model with clinical factors. P value with false discovery control <0.05 was considered as significant. Results: With a mean follow up of 36 months, 18 of LAHNSCC patients and 16 of p16+ OPSCC patients had progression. After adjusting for p16, small µL and ADC values, and large TVLADC of primary tumors pre-RT were significantly associated with superior FFLRDP, FFLP and FFDP in the LAHNSCC (p<0.05), but no diffusion metrics were significant in p16+ oropharynx cancers. Post ad hoc analysis of the p16+ OPSCC only showed that large TVLADC of the total nodal burden pre-RT was significantly associated with inferior FFDP (p=0.05). Conclusion: ADC metrics were associated with different progression patterns in the LAHNSCC and p16+ OPSCC, possibly explained by differences in cancer biology and morphology. A deep understanding of ADC metrics is warranted to establish imaging biomarkers for adaptive RT in HNSCC.

A mid-treatment break and reassessment maintains tumor control and reduces toxicity in patients with hepatocellular carcinoma treated with stereotactic body radiation therapy.

BACKGROUND AND PURPOSE: Patients with hepatocellular carcinoma (HCC) commonly have underlying liver dysfunction with variable tolerance to liver stereotactic body radiation therapy (SBRT). We hypothesized that insertion of a 1-month mid-treatment break would allow us to adapt treatment to the individual patient response, thereby reducing toxicity without compromising local control (LC). MATERIALS AND METHODS: We analyzed HCC patients receiving 3-5 fraction SBRT at our institution from 2005 to 2017. Over this time, patients were offered enrollment on prospective trials assessing individualized adaptive SBRT. Based on normal tissue complication probability and modeling of changes in liver function following a 1-month treatment break between fractions 3 and 4, patients could receive a total of 3 or 5 fractions. Patients not on trial received 3 or 5 fractions without a break. Toxicity was defined as a ≥2 point rise in Child-Pugh (CP) score within 6 months of SBRT. RESULTS: 178 patients were treated with SBRT to 263 HCCs. Median follow-up was 23 months. 86 treatments had a 1-month break. 1-Year LC was 95.4%; this was not different between patients treated with or without a break (p = 0.14). Controlling for tumor size and dose a break was not associated with inferior LC (HR: 0.58, 95%CI: 0.1-3.34, p = 0.54). 54 patients experienced a ≥2 point rise in CP score. Controlling for the number of prior liver directed therapies and mean liver dose, a treatment break reduced the odds of toxicity (OR: 0.42, 95% CI: 0.17-1.03, p = 0.06). CONCLUSION: A one-month mid-treatment break and reassessment may reduce the odds of treatment related toxicity without compromising LC.

Statistical controversies in clinical research: building the bridge to phase II-efficacy estimation in dose-expansion cohorts.

BACKGROUND: Regulatory agencies and others have expressed concern about the uncritical use of dose expansion cohorts (DECs) in phase I oncology trials. Nonetheless, by several metrics-prevalence, size, and number-their popularity is increasing. Although early efficacy estimation in defined populations is a common primary endpoint of DECs, the types of designs best equipped to identify efficacy signals have not been established. METHODS: We conducted a simulation study of six phase I design templates with multiple DECs: three dose-assignment/adjustment mechanisms multiplied by two analytic approaches for estimating efficacy after the trial is complete. We also investigated the effect of sample size and interim futility analysis on trial performance. Identifying populations in which the treatment is efficacious (true positives) and weeding out inefficacious treatment/populations (true negatives) are competing goals in these trials. Thus, we estimated true and false positive rates for each design. RESULTS: Adaptively updating the MTD during the DEC improved true positive rates by 8-43% compared with fixing the dose during the DEC phase while maintaining false positive rates. Inclusion of an interim futility analysis decreased the number of patients treated under inefficacious DECs without hurting performance. CONCLUSION: A substantial gain in efficiency is obtainable using a design template that statistically models toxicity and efficacy against dose level during expansion. Design choices for dose expansion should be motivated by and based upon expected performance. Similar to the common practice in single-arm phase II trials, cohort sample sizes should be justified with respect to their primary aim and include interim analyses to allow for early stopping.

[Treatment of a fractured endodontical instrument in the root canal]. / Behandeling van een gefractureerd endodontisch instrument in het wortelkanaal.

A 53-year-old woman with continuing pain coming from a lower first molar was diagnosed with apical periodontitis, with a retained fractured instrument in the root canal. There are a variety of treatment options for dealing with a corpus alienum in a root canal. In this case it was decided to treat the tooth endodontically, and leave the fractured instrument fragment in situ. The selection of this treatment option was made on the basis of knowledge of the original diagnosis and the success rates of the various treatment options as described in the relevant literature, weighed against the possible risks and their effects on the prognosis. This suggested that the use of a dental operating microscope has a positive impact on the success rates of endodontic treatment The prognosis for endodontic treatment when a fractured instrument fragment is left within the root canal, as in this case, is not significantly reduced. The presence of preoperative periapical pathology, however, is a more clinically significant prognostic indicator.

High-throughput transcriptomic analysis nominates proteasomal genes as age-specific biomarkers and therapeutic targets in prostate cancer.

BACKGROUND: Although prostate cancer (PCa) is hypothesized to differ in nature between younger versus older patients, the underlying molecular distinctions are poorly understood. We hypothesized that high-throughput transcriptomic analysis would elucidate biological differences in PCas arising in younger versus older men, and would nominate potential age-specific biomarkers and therapeutic targets. METHODS: The high-density Affymetrix GeneChip platform, encompassing >1 million genomic loci, was utilized to assess gene expression in 1090 radical prostatectomy samples from patients with long-term follow-up. We identified genes associated with metastatic progression by 10 years post-treatment in younger (age<65) versus older (age⩾65) patients, and ranked these genes by their prognostic value. We performed Gene Set Enrichment Analysis (GSEA) to nominate biological concepts that demonstrated age-specific effects, and validated a target by treating with a clinically available drug in three PCa cell lines derived from younger men. RESULTS: Over 80% of the top 1000 prognostic genes in younger and older men were specific to that age group. GSEA nominated the proteasome pathway as the most differentially prognostic in younger versus older patients. High expression of proteasomal genes conferred worse prognosis in younger but not older men on univariate and multivariate analysis. Bortezomib, a Food and Drug Administration approved proteasome inhibitor, decreased proliferation in three PCa cell lines derived from younger patients. CONCLUSIONS: Our data show significant global differences in prognostic genes between older versus younger men. We nominate proteasomeal gene expression as an age-specific biomarker and potential therapeutic target specifically in younger men. Limitations of our study include clinical differences between cohorts, and increased comorbidities and lower survival in older patients. These intriguing findings suggest that current models of PCa biology do not adequately represent genetic heterogeneity of PCa related to age, and future clinical trials would benefit from stratification based on age.

Safety, efficacy, and long-term follow-up evaluation of perioperative epirubicin, Cisplatin, and capecitabine chemotherapy in esophageal resection for adenocarcinoma.

BACKGROUND: Perioperative epirubicin, cisplatin, and capecitabine (ECC) chemotherapy was evaluated in patients who underwent esophageal resection for adenocarcinoma of the esophagus or gastroesophageal junction (GEJ). METHODS: A cohort of 93 consecutive patients was analyzed. The median follow-up period was 60 months. Source data verification of adverse events was performed by two independent observers. RESULTS: All three planned preoperative chemotherapy cycles were administered to 65 patients (69.9 %). Only 27 % of the patients completed both pre- and postoperative chemotherapy. The reasons for not receiving postoperative adjuvant chemotherapy could be separated in two main problems: toxicity of the preoperative chemotherapy and postoperative problems involving difficulty in recovery and postoperative complications. Finally, 25 patients (27 %), completed three preoperative and three postoperative cycles. Grades 3 and 4 nonhematologic adverse events of preoperative chemotherapy mainly consisted of thromboembolic events (16.2 %) and cardiac complications (7.5 %). A history of cardiac and vascular disease was independently associated with discontinuation of preoperative chemotherapy and the occurrence of grade 3 or higher adverse events. Surgery was performed for 94 % of all the patients who started with ECC chemotherapy. A radical resection (R0) was achieved in 93 % of the patients. A complete pathologic response was observed in 8 % of the patients. During a median follow-up period of 60 months, the median disease-free survival time was 28 months, and the median overall survival time was 36 months. The 3-year overall survival rate was 50 %, and the 5-year overall survival rate was 42 %. CONCLUSION: For patients with adenocarcinoma of the esophagus or GEJ, six cycles of ECC-based perioperative chemotherapy is associated with a relatively high number of adverse events. Although this toxicity did not affect the esophageal resectability rate, this regimen should be used with caution in this patient population.

European consensus meeting of ARM-Net members concerning diagnosis and early management of newborns with anorectal malformations.

The ARM-Net (anorectal malformation network) consortium held a consensus meeting in which the classification of ARM and preoperative workup were evaluated with the aim of improving monitoring of treatment and outcome. The Krickenbeck classification of ARM and preoperative workup suggested by Levitt and Peña, used as a template, were discussed, and a collaborative consensus was achieved. The Krickenbeck classification is appropriate in describing ARM for clinical use. The preoperative workup was slightly modified. In males with a visible fistula, no cross-table lateral X-ray is needed and an anoplasty or (mini-) posterior sagittal anorectoplasty can directly be performed. In females with a small vestibular fistula (Hegar size <5 mm), a primary repair or colostomy is recommended; the repair may be delayed if the fistula admits a Hegar size >5 mm, and in the meantime, gentle painless dilatations can be performed. In both male and female perineal fistula and either a low birth weight (<2,000 g) or severe associated congenital anomalies, prolonged preoperative painless dilatations might be indicated to decrease perioperative morbidity caused by general anesthesia. The Krickenbeck classification is appropriate in describing ARM for clinical use. Some minor modifications to the preoperative workup by Levitt and Peña have been introduced in order to refine terminology and establish a comprehensive preoperative workup.

CUX1 modulates polarization of tumor-associated macrophages by antagonizing NF-κB signaling.

Many solid cancers including pancreatic ductal adenocarcinoma (PDAC) are characterized by an extensive stromal reaction that is accompanied by infiltrating tumor-associated macrophages (TAMs). The role of TAMs in malignant tumors is only partially understood. Previously, we identified the transcription factor CUX1 as an important mediator of tumor progression in PDAC. Interestingly, we found that CUX1 is highly expressed not only in tumor cells but also in TAMs. On the basis of these data, we aimed to elucidate the effects of CUX1 in TAMs in vitro and in vivo. We analyzed the effects of CUX1 on cytokine expression using overexpression and knockdown strategies. The cytokine regulation by CUX1 was further assessed by reporter assays, DNA pulldown experiments and chromatin-immunoprecipitation. CUX1 expression in TAMs was analyzed in human pancreatic cancer tissues and in a genetic mouse model. Immunohistochemical analysis revealed strong expression levels of CUX1 in a distinct subset of TAMs in human PDAC tissues. Furthermore, its expression increased during tumor progression in a genetic mouse model of PDAC. Profiling experiments showed that CUX1 downregulates several NF-κB-regulated chemokines such as CXCL10, which have been associated with M1 polarization and inhibition of angiogenesis and tumor progression. We could demonstrate that CUX1 interacts with NF-κB p65, leading to reduced binding of NF-κB p65 to the chemokine promoters. In addition, CUX1 reduces acetylation of NF-κB p65 at K310 by recruiting HDAC1. Functionally, CUX1 expression in TAMs antagonizes T-cell attraction and enhances angiogenesis in vitro. We identified CUX1 as an important modulator of the TAMs phenotype and function by modulating NF-κB-dependent cytokines.

Evolution of an influenza pandemic in 13 countries from 5 continents monitored by protein microarray from neonatal screening bloodspots.

BACKGROUND: Because of lack of worldwide standardization of influenza virus surveillance, comparison between countries of impact of a pandemic is challenging. For that, other approaches to allow internationally comparative serosurveys are welcome. OBJECTIVES: Here we explore the use of neonatal screening dried blood spots to monitor the trends of the 2009 influenza A (H1N1) pdm virus by the use of a protein microarray. STUDY DESIGN: We contacted colleagues from neonatal screening laboratories and asked for their willingness to participate in a study by testing anonymized neonatal screening bloodspots collected during the course of the pandemic. In total, 7749 dried blood spots from 13 countries in 5 continents where analyzed by using a protein microarray containing HA1 recombinant proteins derived from pandemic influenza A (H1N1) 2009 as well as seasonal influenza viruses. RESULTS: Results confirm the early start of the pandemic with extensive circulation in the US and Canada, when circulation of the new virus was limited in other parts of the world. The data collected from sites in Mexico suggested limited circulation of the virus during the early pandemic phase in this country. In contrast and to our surprise, an increase in seroprevalence early in 2009 was noted in the dataset from Argentina, suggestive of much more widespread circulation of the novel virus in this country than in Mexico. CONCLUSIONS: We conclude that this uniform serological testing of samples from a highly standardized screening system offers an interesting opportunity for monitoring population level attack rates of widespread diseases outbreaks and pandemics.

Leflunomide as part of the treatment for multidrug-resistant cytomegalovirus disease after lung transplantation: case report and review of the literature.

Treatment of cytomegalovirus (CMV) disease in transplant patients is challenging and, with antiviral resistance to first-line drugs, it remains uncertain which treatment algorithm to follow. Some data suggest that leflunomide, a pyrimidine synthesis inhibitor, can be used to treat resistant CMV infections. We report a 57-year-old CMV immunoglobulin-G (IgG)-seronegative woman, who received a bilateral lung transplant (LuTx) from a CMV IgG-positive donor with CMV primary disease. The CMV strain was genotypically resistant to ganciclovir, foscarnet, and cidofovir. After starting leflunomide as add-on therapy to a multidrug anti-CMV regimen, viral load declined substantially in 2 months without adverse events. This experience is discussed against the background of existing literature on the use of leflunomide as an anti-CMV agent in LuTx recipients.

Combined implantation of CD34+ and CD14+ cells increases neovascularization through amplified paracrine signalling.

Cell therapy strategies that use adult peripheral blood-derived CD34⁺ progenitor cells are hampered by low cell numbers and the infrequent cellular incorporation into the neovasculature. Hence, the use of CD34⁺ cells to treat ischaemic diseases is under debate. Interaction between CD34⁺ cells and CD14⁺ cells results in superior endothelial differentiation of CD14⁺ cells in vitro, indicating that cell therapy approaches utilizing both CD34⁺ and CD14⁺ cells may be advantageous in therapeutic neovascularization. Here, human CD34⁺ and CD14⁺ cells were isolated from adult peripheral blood and implanted subcutaneously into nude mice, using matrigel as the carrier. Combined implantation of human CD34⁺ and CD14⁺ cells resulted in superior neovascularization, compared to either cell type alone, albeit incorporation of human cells into the murine vasculature was not observed. Human CD34⁺ and CD14⁺ cells produced and secreted a pentad of pro-angiogenic mediators, such as HGF, MCP-1 and IL-8, bFGF and VEGFa in monoculture. The production and secretion of pro-angiogenic mediators by CD14⁺ cells was highly amplified upon incubation with conditioned medium from CD34⁺ cells. In vivo, neovascularization of matrigel implants did not rely on the endothelial differentiation and incorporation of CD34⁺ or CD14⁺ cells, but depended on the paracrine effects of IL-8, MCP-1, HGF, bFGF and VEGFa secreted by implanted cells. Administration of this growth factor/cytokine pentad using matrigel as a carrier results in cell recruitment and microvessel formation equal to progenitor cell-induced neovascularization. These data provide new insights on neovascularization by cell therapy and may contribute to new strategies for the treatment of ischaemic diseases.

Profiling of humoral immune responses to influenza viruses by using protein microarray.

The emergence of pandemic A(H1N1) 2009 influenza showed the importance of rapid assessment of the degree of immunity in the population, the rate of asymptomatic infection, the spread of infection in households, effects of control measures, and ability of candidate vaccines to produce a response in different age groups. A limitation lies in the available assay repertoire: reference standard methods for measuring antibodies to influenza virus are haemagglutination inhibition (HI) assays and virus neutralization tests. Both assays are difficult to standardize and may be too specific to assess possible partial humoral immunity from previous exposures. Here, we describe the use of antigen-microarrays to measure antibodies to HA1 antigens from seven recent and historical seasonal H1, H2 and H3 influenza viruses, the A(H1N1) 2009 pandemic influenza virus, and three avian influenza viruses. We assessed antibody profiles in 18 adult patients infected with A(H1N1) 2009 influenza virus during the recent pandemic, and 21 children sampled before and after the pandemic, against background reactivity observed in 122 persons sampled in 2008, a season dominated by seasonal A(H1N1) influenza virus. We show that subtype-specific and variant-specific antibody responses can be measured, confirming serological responses measured by HI. Comparison of profiles from persons with similar HI response showed that the magnitude and broadness of response to individual influenza subtype antigens differs greatly between individuals. Clinical and vaccination studies, but also exposure studies, should take these findings into consideration, as they may indicate some level of humoral immunity not measured by HI assays.

Shockwave treatment for medial tibial stress syndrome in athletes; a prospective controlled study.

Objective The purpose of this study was to describe the results of two treatment regimens for medial tibial stress syndrome (MTSS); a graded running programme and the same running programme with additional shockwave therapy (extracorporeal shockwave therapy; ESWT). Design A prospective observational controlled trial. Setting Two different sports medicine departments. Participants 42 athletes with MTSS were included. Intervention Patients from one hospital were treated with a graded running programme, while patients from the other hospital were treated with the same graded running programme and focused ESWT (five sessions in 9 weeks). Main Outcome Measures Time to full recovery (the endpoint was being able to run 18 min consecutively without pain at a fixed intensity). Results The time to full recovery was significantly faster in the ESWT group compared with the patients who only performed a graded running programme, respectively 59.7±25.8 and 91.6±43.0 days (p=0.008). Conclusions This prospective observational study showed that MTSS patients may benefit from ESWT in addition to a graded running programme. ESWT as an additional treatment warrants further investigation in a prospective controlled trial with the addition of randomisation and double blinding.

Histopathology in the isolated chicken eye test and comparison of different stainings of the cornea.

The isolated chicken eye (ICE) test, developed at our Institute, is accepted by the OECD for identification of severe eye irritants. The OECD ICE Guideline (No. 438) encourages preservation of the treated eyes for possible histopathology of the cornea, which is believed to strengthen evidence of absence or presence of irritation and to help clarify borderline effects by assessment of the corneal Depth-of-Injury. Histopathology of the cornea in addition to the normal slit-lamp microscope assessment of corneal effects has already been performed routinely in ICE tests at our Institute, using two standard stainings (H&E and PAS). In this study, three other stainings (AZAN, EVG and Trichrome), more specific for collagen-rich membranes such as basement- and Bowman's membranes were examined with corneas exposed to four model compounds ranging from non- to severely irritating (corrosive). PAS appeared to be the superior staining method. Surprisingly, the well-known eye corrosive sodium hydroxide (NaOH, solid) did not visibly compromise the integrity of Bowman's or the basement membrane. Based on our experience, histopathology of the treated cornea is confirmative in relation to the standard assessment of eye irritation by slit-lamp observation in the ICE and in certain cases can help to evaluate borderline effects. Besides establishing the depth of injury, additional investigation of corneal limbal stem cell damage after chemical exposure might be appropriate to determine reversibility or irreversibility of eye effects.

Robot-assisted thoracoscopic oesophagectomy for cancer.

BACKGROUND: Thoracoscopic oesophagectomy was introduced to reduce the morbidity of transthoracic oesophagectomy. The aim was to assess the short- and mid-term results of robot-assisted thoracoscopic oesophagectomy for oesophageal cancer. METHODS: Between October 2003 and May 2007, 47 patients with resectable oesophageal cancer underwent robot-assisted thoracoscopic oesophagectomy. Clinical data were collected prospectively. RESULTS: Conversion to thoracotomy was necessary in seven patients. Median operating time was 450 min and median blood loss 625 ml. Median postoperative ventilation time was 1 day, intensive care stay 3 days and hospital stay 18 days. Twenty-one of 47 patients had pulmonary complications. Three patients died in hospital. A median of 29 (range 8-68) lymph nodes was dissected and R0 resection was achieved in 36 patients. Twenty-three patients had stage IVa disease. After a median follow-up of 35 months, median disease-free survival was 15 (95 per cent confidence interval 12 to 18) months. CONCLUSION: Robot-assisted thoracoscopic oesophagectomy was oncologically acceptable. Operating time, blood loss and pulmonary complications might decrease with further experience.