Margin Recurrence Research Articles

HPB SO54 - Outcomes of Isolated Bile Duct Resection for Cholangiocarcinoma; More Than 15 Years Experience in a Single Tertiary HPB Centre

Abstract Background Cholangiocarcinoma of the extrahepatic biliary tree usually requires a major resection to achieve clear margins with adequate lymphadenectomy. For perihilar tumours this involves extended liver resection with bile duct resection whilst distal tumours require pancreaticoduodenectomy. Occasionally a combination of both (hepato-pancreaticoduodenectomy) is required. These procedures are associated with high morbidity and mortality. In a small number of patients, cholangiocarcinoma is confined to the extrahepatic bile duct with no involvement of the liver or pancreas and a bile duct resection alone is an option. We reviewed the outcomes of patients who underwent bile duct resection for cholangiocarcinoma in our unit. Method We identified all patients who underwent bile duct resection and hepaticojejunostomy for cholangiocarcinoma between June 2007 and June 2023 in our centre from a prospectively maintained database. Patient demographics, complications, histology, resection margin status, follow-up, recurrence, and survival were recorded. Time to recurrence and overall survival were analysed using Kaplan Meier analysis. Results Thirteen patients underwent bile duct resection and hepaticojejunostomy for cholangiocarcinoma. 12 (92%) were male and the median (range) age was 72 (41-82). No patients received neoadjuvant treatment. 3 (23%) patients developed postoperative complications with 1 (7.7%) perioperative mortality. R0 margin was achieved in 6 (46%). The median (range) postoperative stay was 7 (5-25) days. 8 (61.5%) patients received adjuvant chemotherapy. 7 patients (53.8%) developed recurrent disease at a median of 12 (IQR 8-54) months following surgery. The most common sites of recurrence were the liver (23.1%) followed by local recurrence (15.4%). The median survival was 38 (IQR 20-95) months. Conclusion Extrahepatic bile duct resection with hepaticojejunostomy is an option for patients with cholangiocarcinoma of the extrahepatic bile duct without macroscopic involvement of the liver or pancreas. In our series this procedure was associated with a low morbidity and perioperative mortality with acceptable recurrence rates and overall survival despite only modest R0 resection rates. Isolated bile duct resection with hepaticojejunostomy should be considered for tumours without macroscopic involvement of the liver or pancreas, especially in patients of borderline fitness for a more extensive resection.

SURG-53. LONG TERM FOLLOW-UP OF RESECTION PLUS CESIUM-131 BRACHYTHERAPY FOR PREVIOUSLY IRRADIATED RECURRENT BRAIN METASTASES

Abstract BACKGROUND Recurrent brain metastases (rBM) after previous radiosurgery present a clinical dilemma, as the advantages of reirradiation need to be weighed against the potential of significant radiation toxicity. Salvage resection with Cs-131 brachytherapy offers improved dosimetry due to reduced integral dose to healthy brain compared to repeat radiosurgery. We previously reported initial results of rBM treated with resection and salvage Cs131 brachytherapy; we present an updated analysis of tumor control with extended follow-up. METHODS We analyzed consecutive patients with rBM previously treated with radiosurgery, who underwent salvage resection plus implantation of Cs131 seeds (GammaTile, GT Medical Technologies). The prescribed brachytherapy dose was 60 Gy at 5mm from the cavity. Median follow-up was calculated using reverse Kaplan-Meier. Local recurrence was defined by new nodular contrast enhancement with hyperperfusion within 5mm of the resection cavity. Marginal recurrence was defined as >5mm but not beyond 1cm from the cavity. Local control and overall survival (OS) from brachytherapy were analyzed using Kaplan-Meier. RESULTS Twenty-five patients underwent Cs131 implantation in 30 tumor cavities. The median presurgical rBM maximal diameter was 2.95 cm (range 1.1-6.3). The most common histology was lung adenocarcinoma (n=8, 27%) followed by breast (n=7, 23%) and renal cell (n=3, 10%). Radiographic gross- or near-total resection was achieved in 80% of lesions. The median number of Cs131 seeds implanted was 17, (range 6-30), (median strength 3.5 U/seed). With median follow-up of 37 months (95%CI:29-45), twelve and 24-month OS was 55% and 41%, respectively. Four tumors recurred (3 in-field, one marginal) for a 1- and 2-year local control rate of 87% and 81%, respectively. Data for adverse radiation effects is under analysis and will be presented. CONCLUSIONS With over 3 years of follow-up, intraoperative brachytherapy with collagen-embedded Cs131 implants was associated with durable local control for this challenging clinical scenario. A randomized Phase II trial of Cs131 vs. standard of care for rBM (NCT04690348) is actively accruing.

Recurrent Patterns in Patients With Nasopharyngeal Caricinoma and Risks Leading to Inaccurate Delineation in Marginal Failure in the Era of Intensity-Modulated Radiotherapy.

To investigate the failure patterns of recurrent nasopharyngeal carcinoma (NPC), especially to identify the relationship between the recurrent-prone anatomic structures and the tumor regression sites after the introduction of chemotherapy (IC). A cohort of 1121 non-metastatic patients with NPC was retrospectively enrolled. The pretreatment and recurrent images of each patient were registered to the planning CT. Tumor regression sites after IC (Vicr) overlapped with recurrent tumor (rGTV) were evaluated for the delineation accuracy and dose sufficiency in marginal failure patients. A total of 126 (11.24%) experienced tumor recurrence. Re-evaluation of 12 patients with local marginal recurrence, their rGTV within Vicr predominantly located at choanae, sphenoidal sinus, and cavernous sinus. The regression sites did not receive the full 70 Gy but over half receiving with 60Gy. Analysis from marginal failure that exempts tumor regression sites from GTV or an insufficient prescription dose of less than 70 Gy may contribute to marginal failure.

Robotic Versus Laparoscopic Gastrectomy for Gastric Cancer: The Largest Systematic Reviews of 68,755 Patients and Meta-analysis.

This meta-analysis aimed to compare the efficacy of robotic gastrectomy (RG) and laparoscopic gastrectomy (LG) in treating gastric cancer (GC). A comprehensive literature search across PubMed, MEDLINE, and Web of Science identified 86 eligible studies, including 68,755 patients (20,894 in the RG group and 47,861 in the LG group). The analysis revealed that RG was associated with superior outcomes in several areas: more lymph nodes were harvested, intraoperative blood loss was reduced, postoperative hospital stays were shorter, and the time to first flatus and oral intake was shortened (all p<0.001). Additionally, RG resulted in lower incidences of conversion to open surgery (OR=0.62, p=0.004), reoperation (OR=0.68, p=0.010), overall postoperative complications (OR=0.82, p<0.001), severe complications (OR=0.65, p<0.001), and pancreatic complications (OR=0.60, p=0.004). However, RG had longer operative times and higher costs (both p<0.001). No significant differences were found between RG and LG in terms of resection margin distance, mortality, anastomotic leakage, or recurrence rates. RG is a safe and effective surgical option for patients of GC, but further improvements in operative duration and costs are needed.

S2093 Exploring Proton Pump Inhibitor Optimization of Post-RYGB Marginal Ulceration Recurrence

S2093 Exploring Proton Pump Inhibitor Optimization of Post-RYGB Marginal Ulceration Recurrence

Local extension findings on MRI compensate for the ability of pathological staging to predict oncological outcome.

We investigated whether local extension findings on preoperative MRI and excisional pathology are associated with positive surgical margin and biochemical recurrence after robot-assisted radical prostatectomy. We identified 704 of our patients that underwent robot-assisted radical prostatectomy between 2012 and 2020, and extracted the 326 patients who had preoperative MRI scans and a radiologist reading. These patients were classified into groups according to the presence of local extension on MRI and pathological findings: ≤ cT2pT2 (195 cases), ≤ cT2pT3 (55 cases), cT3pT2 (31 cases), and cT3pT3 (45 cases). We compared positive surgical margin and biochemical recurrence between them. Median age was 69years, positive surgical margin rate was 20.2%, and five-year biochemical recurrence rate was 20.3%. Of the 226 patients without local invasion on excisional pathology, those with local extension on MRI (cT3pT2) had relatively higher positive surgical margin rate (29.0% vs. 14.4%, p = 0.05) and significantly higher five-year biochemical recurrence rate (25.8% vs. 9.3%, p = 0.01) than those without local extension on MRI (≤ cT2pT2). Similarly, among the 100 patients with local extension on excisional pathology, those with cT3pT3 had relatively higher positive surgical margin (37.8% vs. 21.8%, p = 0.08) and significantly higher five-year biochemical recurrence (53.3% vs. 29.3%, p = 0.01) than those with ≤ cT2pT3. In multivariate analysis, local extension on MRI was an independent predictor of biochemical recurrence (OR 2.1, 95%CI 1.1-3.9, p = 0.01). Local extension on MRI is a prognostic factor independent of pathological stage. The use of MRI may complement the prognostic value of excisional pathology of prostate cancer.

Pediatric Desmoid Tumor of the Head and Neck: A Systematic Review and Modified Framework for Management by Age Group.

Unlike in adults, pediatric head and neck desmoid tumors (DTs) have greater capacity to interfere with normal anatomical development. Therefore, adequate interventions and management must be defined. We aimed to provide the most comprehensive systematic review on pediatric head and neck DTs to date, including assessment of lesion location predominance, intervention, and management, and examination of any associations between age and outcomes like surgical margin status, recurrence, and complications. A systematic literature review was conducted between January 1990 and December 2023 using PubMed, Scopus, and MEDLINE databases following the Preferred Reporting Items for Systematic Review and Meta-Analyses 2020 guidelines. We aimed to elucidate intervention and management strategies by studying various outcomes in 0-11 and 12-21 year olds. The literature search yielded 44 studies, totaling 121 patients. Most head and neck DTs localized to the mandible, cranium, and neck; occurred early (P = 4.18 years); and underwent local resection with positive margins. Older and younger patients shared no difference in complication or recurrence rates. We found recurrence is likely to occur with positive margins. Because standard treatment of DTs is surgical resection with negative margins, if technically feasible with reasonable associated morbidity, we suggest additional resection of the tumor to achieve negative margins. We also recommend more robust follow-up data collection, not only due to desmoid's high recurrence and data paucity in patients older than 12 years, but also, to better establish best management practices.

Evaluation of the results of loop electrosurgical excision procedure surgical margin positivity and recurrence

Evaluation of the results of loop electrosurgical excision procedure surgical margin positivity and recurrence

Patterns and Predictors of Recurrence After Curative Resection of Colorectal Liver Metastasis (CRLM).

Our study aims to determine the predictors and patterns of relapses after curative colorectal liver metastasis (CRLM) resection. A single-centre, retrospective study of CRLM patients operated between 2010 and 2022 was performed. The site of first recurrence was either hepatic (marginal (≤ 1cm) or extramarginal), extrahepatic, or both. Factors that predicted relapse patterns and overall survival were determined by multivariable Cox regression analysis with backward elimination of variables. The study consisted of 258 patients, with a similar proportion of synchronous (144; 56%) and metachronous(114; 43%) metastasis. At a 43-month median follow-up, 156 patients (60.4%) developed recurrences with 33 (21.1%) in the liver, 62(24.03%) extra-hepatic recurrences, and 58 (22.48%) having both. Isolated marginal liver relapses were seen in seven (9.89%) liver recurrence patients. The median overall and relapse-free survivals were 38months (30-54) and 13months (11-16), respectively. The 3-year liver-relapse-free survival was 54.4% (44.9-60.6). Size of liver metastases > 5cm (HR 2.06 (1.34-3.17), involved surgical margins (HR 2.16 (1.27-3.68)), and adjuvant chemotherapy (HR 1.89 (1.07-3.35)) were predictors of hepatic recurrences. Node positivity of primary (HR 1.61 (1.02-2.56)), presence of baseline extra-hepatic metastases (HR 0.30 (0.18-0.51)), size of liver metastases > 5cm (HR 2.02 (1.37-2.99)), poorly differentiated histology (HR 2.25 (1.28-3.49)), presence of LVI (HR 2.25 (1.28-3.94)), and adjuvant chemotherapy (HR 2.15 (1.28-3.61)) were predictors of extra-hepatic recurrences. The study found majority relapses occurred at extrahepatic sites whilst isolated marginal recurrences were few. The consistent predictors of recurrence were size and inability to deliver adjuvant therapy. A tailored adjuvant therapy might improve outcomes after liver metastasectomy in colorectal cancers.

399 Cancer Recurrence in Positive Margin Partial Nephrectomies: 5-Year Results from the West of Scotland

Abstract Aim Provide insight into the incidence of disease recurrence following a positive margin partial nephrectomy in Renal cancer patients. Allowing the analysis of the current surveillance protocols for early detection of disease recurrence. Method A retrospective review of all patients undergoing Partial Nephrectomies (PN) within a single centre between 2016 and 2021 was performed. Demographic data including age and sex, as well as tumour-specific data of histology, RENAL score, tumour margin, surveillance, and disease recurrence was recorded. Follow-up was performed as per WOSCAN guidance. Results 255 patients underwent PN: 79 (31%) open (OPN) and 176 (69%) robotic-assisted procedures (RALPN). OPN was performed in higher risk cancers with a higher risk of positive margin compared to RALPN (10.1% vs 6.25%). The median follow-up time was 35 months. 3 patients with positive margins had recurrence; all were pT3 cancer following OPN of which 2 had metastatic and 1 patient had local recurrence. 18 positive margin patients (95%) were compliant with WOSCAN surveillance guidelines. Conclusions OPN was performed for more complex tumours which had a higher risk of positive margins and thus recurrence. Regional data can be used to better counsel patients, however further work should assess any evolving change in RALPN positive margin rates as more complex tumours are attempted robotically.

Margin status, adjuvant treatment and recurrence in buccal cancer

ObjectiveTo assess the prognostic importance of margin in resected buccal cancer within a framework of risk factor-driven postoperative adjuvant treatment. Materials and MethodsConsecutive, treatment naïve patients undergoing primary surgical treatment for buccal cancer. Margin was defined as clear (≥5 mm), close (1–4 mm) and involved (<1 mm). Main outcome was association of margin with local recurrence free survival (LRFS). Subgroup analysis of close margin was performed according to receipt or no receipt of adjuvant treatment. A numerical margin cut-off in mm that could independently predict LRFS was sought to be identified. ResultsOf the 167 patients included, the frequency of clear, close and involved margins was 50 (30 %), 78 (47 %) and 39 (23 %) respectively, among whom 52 %, 44 % and 98 % received postoperative adjuvant treatment respectively. Clear and close margins had similar 3-year LRFS (89 % and 96 % respectively), while involved margin had worse 3-year LRFS at 65 %. Involved margin was confirmed to be strongly and independently associated with worse LRFS. Within close margin, receipt and no receipt of adjuvant treatment had similar 3-year LRFS (92 % and 100 % respectively). A margin cut-off of 2 mm was identified at or above which LRFS approximated that of clear margin. ConclusionsThis single center cohort study of patients with resected buccal cancer suggests that close margin is distinct from and has a better LRFS than involved margin. A subset of close margin, with margin size ≥ 2 mm and no other adverse features, might be spared adjuvant treatment without compromising outcomes.

Patterns of recurrence after radiotherapy for high-risk neuroblastoma: Implications for radiation dose and field

BackgroundPrognosis for patients with high-risk neuroblastoma (HR-NBL) is guarded despite aggressive therapy, and few studies have characterized outcomes after radiotherapy in relation to radiation treatment fields. MethodsMulti-institutional retrospective cohort of 293 patients with HR-NBL who received autologous stem cell transplant (ASCT) and EBRT between 1997–2021. LRR was defined as recurrence at the primary site or within one nodal echelon beyond disease present at diagnosis. Follow-up was defined from the end of EBRT. Event-free survival (EFS) and OS were analyzed by Kaplan-Meier method. Cumulative incidence of locoregional progression (CILP) was analyzed using competing risks of distant-only relapse and death with Gray’s test. ResultsMedian follow-up was 7.0 years (range: 0.01–22.4). Five-year CILP, EFS, and OS were 11.9 %, 65.2 %, and 77.5 %, respectively. Of the 31 patients with LRR and imaging review, 15 (48.4 %) had in-field recurrences (>12 Gy), 6 (19.4 %) had marginal failures (≤12 Gy), and 10 (32.3 %) had both in-field and marginal recurrences. No patients receiving total body irradiation (12 Gy) experienced marginal-only failures (p = 0.069). On multivariable analyses, MYCN amplification had higher risk of LRR (HR: 2.42, 95 % CI: 1.06–5.50, p = 0.035) and post-consolidation isotretinoin and anti-GD2 antibody therapy (HR: 0.42, 95 % CI: 0.19–0.94, p = 0.035) had lower risk of LRR. ConclusionsDespite EBRT, LRR remains a contributor to treatment failure in HR-NBL with approximately half of LRRs including a component of marginal failure. Future prospective studies are needed to explore whether radiation fields and doses should be defined based on molecular features such as MYCN amplification, and/or response to chemotherapy.

Long-term outcomes of single-port laparoscopic hepatectomy for hepatocellular carcinoma: a retrospective comparative analysis.

Numerous efforts have been made to achieve minimally invasive surgery, such as single-port laparoscopic surgery. However, few studies have provided long-term follow-up information, and the number of patients with hepatocellular carcinoma (HCC) in previous studies has been small. The purpose in this study is to compare the long-term oncological outcomes of HCC patients who underwent single-port laparoscopic hepatectomy (SPLH) with those of patients who underwent multiport laparoscopic hepatectomy (MPLH). We retrospectively reviewed the medical records of 135 patients with HCC who underwent laparoscopic liver between January 2008 and December 2018. Of the 135 patients, 53 underwent MPLH, and 82 underwent SPLH. From January 2008 to December 2018, 135 patients underwent laparoscopic hepatectomy for HCC. Among them, 82 patients underwent SPLH, and 53 patients underwent MPLH. Neither long-term overall survival (P = 0.849) nor recurrence-free survival (P = 0.057) differed significantly between the 2 groups, even though the recurrence rate was higher in the SPLH group. In the univariable analysis of risk factors for recurrence, multiple tumors, SPLH method, and portal vein invasion were statistically significant (P < 0.05). Multivariable analysis showed that the SPLH method and portal vein invasion were independent adverse prognostic factors for recurrence-free survival. In terms of both short-term and long-term outcomes, the SPLH method seems to be a feasible approach for HCC in select patients. Because the potential risk of margin recurrence might produce poor oncological outcomes, strict patient selection is essential to ensure that an adequate safety margin can be secured.

Comparing advanced platforms for local excision of rectal lesions.

Transanal surgery facilitates organ preservation in select patients with benign and early malignant rectal lesions to avoid the functional consequences of radical surgery. The transanal endoscopic microsurgery (TEM) platform created a standard for local excision with lower margin positivity and recurrence rates than traditional transanal excision. The single-port robot (SP r) presents a promising alternative transanal platform. The goal of this study was to compare perioperative and pathologic outcomes of TEM and SP r for excision of rectal lesions. A review of consecutive patients who underwent local excision of rectal lesions at a tertiary referral center from 1/2001 to 5/2022 was performed. Cases were stratified into TEM or SP rTAMIS in a 1:1 propensity score-matched cohort, adjusting for all baseline characteristics. Clinical, tumor-specific, and perioperative outcomes were compared using χ2, and Mann-Whitney U-tests. The main outcomes were oncologic quality measures, complications, and operative time. Matching resulted 50 patients in each cohort. Groups had similar age, gender, body mass index, comorbidity, diagnosis, lesion characteristics, and neoadjuvant chemoradiation rates. There were no intraoperative complications in either cohort. Three SP rTAMIS cases were converted intraoperatively; there were no conversions in TEM. SP rTAMIS had significantly shorter operative times than TEM (mean 104 vs. 245, p = 0.027). The rates of positive distal margins (2% TEM, 0% SP rTAMIS) and piecemeal resection (4% TEM, 0% SP rTAMIS) were similar. SP rTAMIS had significantly lower postoperative morbidity rates than TEM (9% vs. 20%, p = 0.031). There was no mortality in either cohort. SP robotics provided high-quality outcomes similar to TEM for local excision of rectal lesions. SP robotics had faster operative time with comparable clinical and oncologic outcomes to TEM. These early data are promising for expanding use of SP robotic platforms.

Регресс ринофимы на фоне фотодинамической терапии базальноклеточного рака кожи кончика носа

The article describes a case of regression of rhinophyma against the background of photodynamic therapy of basal cell carcinoma of the skin of the nose tip. After a single session of photodynamic therapy using a systemic photosensitizer based on chloride (photoran), there was a significant decrease in the size of the nose (rhinophyma), the disappearance of erythema, puffiness, and the formation of the initial contours of the face of this anatomical area. Despite the marginal recurrence of basal cell carcinoma after six months at the site of previous treatment and a repeat session of photodynamic therapy, after one year of dynamic follow-up, remission of basal cell carcinoma and regression of rhinophyma persist. The described method of treatment is atraumatic, easily reproducible, well tolerated by patients, safe and allows patients with basal cell carcinoma in combination with rhinophyma to achieve complete remission of both diseases.

ASO Author Reflections: Future Perspectives in Surgical Management of Distal Cholangiocarcinoma: Insights from Surgical Margin Status and Recurrence Patterns.

ASO Author Reflections: Future Perspectives in Surgical Management of Distal Cholangiocarcinoma: Insights from Surgical Margin Status and Recurrence Patterns.

Anatomical assessment of local recurrence site in breast cancer patients after breast reconstruction and post-mastectomy radiotherapy: implications for radiation volumes and techniques.

Post-mastectomy radiotherapy (PMRT) improves local control rates and survival in patients with adverse prognostic features. The dose coverage to target volumes is critical to yield maximum benefit to treated patients, increasing local control and reducing risk of toxicity. This study aims to assess patterns of breast cancer relapse in patients treated with mastectomy, breast reconstruction and PMRT. Breast cancer patients treated with PMRT between 1992 and 2017 were retrospectively reviewed. Clinical and pathological characteristics of patients were collected. Recurrences were defined as "in field," "marginal" or "out of field." Survival analyses were performed in relation to progression-free survival (PFS) and overall survival (OS). Correlation between baseline features was explored. Data of 140 patients are collected. After a median follow-up time of 72 months, median PFS and OS of 63 and 74 months were detected, respectively. Neoadjuvant chemotherapy, lympho-vascular space invasion (LVI) and size of primary tumor were all significantly associated with worst PFS and OS. Ten patients developed local recurrence: 30% "in field," 30% marginal recurrences, 20% "out of field" and 20% both "in field" and "out of field." No recurrence was detected under the expander, 80% above the device and 20% patients relapsed on IMN chain. The mean distant relapse-free survival was 39 months. Overall, 39 of 140 patients developed distant metastases. The onset of local-regional relapses occurred mainly above the expander/prosthesis, underlying the importance of inclusion of the subcutaneous tissues within the target volume. In order to refine new contouring recommendations for PMRT and breast reconstruction, future prospective studies are needed.

Oncoplastic breast-conserving surgery (OBCS) vs. mastectomy with reconstruction: a comparison of outcomes in an underserved population.

Oncoplastic breast-conserving surgery (OBCS) has demonstrated superior cosmetic outcomes to traditional breast-conserving surgery (BCS) while maintaining oncologic safety. While prior studies have compared OBCS to mastectomy, there is a scarcity of literature on the impact of social determinants of health on outcomes. Furthermore, although traditionally tumors larger than 5 cm and multifocal disease were treated with mastectomy, the literature has now shown OBCS to be safe in treating such disease. As a result, patients with large or multifocal tumors could be eligible for both mastectomy and OBCS, which prompts the need for comparison between the two. Thus, the aim of our study was to compare OBCS and mastectomy with reconstruction using BREAST-Q and oncologic outcome measures, as well as stratify these outcomes based on race, ethnicity, and body mass index (BMI). A retrospective chart review was performed for 57 patients treated with OBCS and 204 patients treated with mastectomy with reconstruction from 2015 to 2021. Variables including age, race, ethnicity, BMI, insurance status, surgery type, pathology, recurrence, and complications were recorded. Patient-reported outcomes (PROs) were recorded using BREAST-Q pre- and post-operatively. Despite having a higher BMI (P<0.001), OBCS yielded higher "satisfaction with breast" and "satisfaction with outcome" than mastectomy (P=0.02 and P=0.02, respectively). When stratified by race, there were no statistical differences in the PROs between the two surgeries for Hispanic nor African American patients. OBCS had a significantly lower rate of infection and fewer additional surgeries than mastectomy (P=0.004 and P<0.001, respectively). There were no differences in positive margin rate or recurrence rate between the groups. In our study, OBCS yielded better PROs than mastectomy while maintaining oncologic safety and resulting in fewer surgeries and complications. These excellent outcomes in a majority non-Caucasian cohort support the utilization of OBCS for underserved, minority populations. Larger studies evaluating PROs in diverse and uninsured groups are needed to reinforce these conclusions.

Comparison of different target volume delineation strategies based on recurrence patterns in adjuvant radiotherapy for glioblastoma.

Radiation Therapy Oncology Group (RTOG) and the European Organization for Research and Treatment of Cancer (EORTC) recommendations are commonly used guidelines for adjuvant radiotherapy in glioblastoma. In our institutional protocol, we delineate T2-FLAIR alterations as gross target volume (GTV) with reduced clinical target volume (CTV) margins. We aimed to present our oncologic outcomes and compare the recurrence patterns and planning parameters with EORTC and RTOG delineation strategies. Eighty-one patients who received CRT between 2014 and 2021 were evaluated retrospectively. EORTC and RTOG delineations performed on the simulation computed tomography and recurrence patterns and planning parameters were compared between delineation strategies. Statistical Package for the Social Sciences (SPSS) version 23.0 (IBM, Armonk, NY, USA) was utilized for statistical analyses. Median overall survival and progression-free survival were 21 months and 11 months, respectively. At a median 18 month follow-up, of the 48 patients for whom recurrence pattern analysis was performed, recurrence was encompassed by only our institutional protocol's CTV in 13 (27%) of them. For the remaining 35 (73%) patients, recurrence was encompassed by all separate CTVs. In addition to the 100% rate of in-field recurrence, the smallest CTV and lower OAR doses were obtained by our protocol. The current study provides promising results for including the T2-FLAIR alterations to the GTV with smaller CTV margins with impressive survival outcomes without any marginal recurrence. The fact that our protocol did not result in larger irradiated brain volume is further encouraging in terms of toxicity.

CLASSICA: Validating artificial intelligence in classifying cancer in real time during surgery.

Treatment pathways for significant rectal polyps differ depending on the underlying pathology, but pre-excision profiling is imperfect. It has been demonstrated that differences in fluorescence perfusion signals following injection of indocyanine green (ICG) can be analysed mathematically and, with the assistance of artificial intelligence (AI), used to classify tumours endoscopically as benign or malignant. This study aims to validate this method of characterization across multiple clinical sites regarding its generalizability, usability and accuracy while developing clinical-grade software to enable it to become a useful method. The CLASSICA study is a prospective, unblinded multicentre European observational study aimed to validate the use of AI analysis of ICG fluorescence for intra-operative tissue characterization. Six hundred patients undergoing transanal endoscopic evaluation of significant rectal polyps and tumours will be enrolled in at least five clinical sites across the European Union over a 4-year period. Video recordings will be analysed regarding dynamic fluorescence patterns centrally as software is developed to enable analysis with automatic classification to happen locally. AI-based classification and subsequently guided intervention will be compared with the current standard of care including biopsies, final specimen pathology and patient outcomes. CLASSICA will validate the use of AI in the analysis of ICG fluorescence for the purposes of classifying significant rectal polyps and tumours endoscopically. Follow-on studies will compare AI-guided targeted biopsy or, indeed, AI characterization alone with traditional biopsy and AI-guided local excision versus traditional excision with regard to marginal clearance and recurrence.