Patterns Of Local Recurrence Research Articles

Could elective nodal irradiation for locally advanced rectal cancer be omitted in the context of total neoadjuvant therapy? An analysis of the recurrence sites of rectal cancer.

This study aims to optimize neoadjuvant radiotherapy target area for locally advanced rectal cancer (LARC) patients undergoing total neoadjuvant therapy (TNT) by examining local recurrence patterns. We retrospectively analyzed the clinical data of rectal cancer patients who undergone local recurrence after surgery. Recurrence sites were categorized and compared with initial diagnosis imaging, focusing on visible and suspicious lesions. Of the 126 patients who met our criteria, 186 lesions were analyzed. Within these, 75.40% of cases (95/126) and 83.33% of lesions (155/186) were located within the pelvic cavity. Conversely, 3.97% of cases (5/126) and 3.33% of lesions (6/186) occurred outside the pelvic cavity. Additionally, 20.63% of cases (26/126) and 13.44% of lesions (25/186) were found in both regions. Recurrences were predominantly observed in mesenteric regions (MR) (40.86%, 76/186) and presacral regions (PR) (32.26%, 60/186). In addition, 86.51% of patients (109/126) had recurrent lesions in HRA and the suspected lesions areas. Further analysis showed that initial CEA levels and adjuvant therapy types were identified as independent predictors for recurrence in MR/PR and initially suspected lesions. 86.51% of patients had recurrent lesions in HRA and the suspected lesions areas. The MR, PR, and areas of initial suspicious lesions are high-risk zones for post-surgical recurrence of LARC. Exploratory study of involved-field irradiation (IFI) can be carried out in the context of TNT in LARC.

Interpreting the patterns of local failure following postoperative volumetric-modulated arctherapy in oral cavity and oropharynx cancers: Impact of the different methods of analysis

PurposeIntensity-modulated radiation therapy or volumetric-modulated arctherapy is nowadays the recommended radiation technique for the treatment of head and neck cancers. However, by providing a significant dose gradient between target volumes and organs at risk, there is a risk of target missing and thus recurrence in case of inadequate delineation. It is therefore necessary to determine the origin of these recurrences to improve clinical practice. Over the past years, different methods have been described for the analysis of recurrences. Using the patterns of failure of patients with oral cavity and oropharynx carcinoma, treated with postoperative volumetric-modulated arctherapy in our institution, the purpose of this work was to analyse the sites of local recurrences and to evaluate the disparity in the classification of recurrences when different methods were used. Material and methodsBetween 2011 and 2019, 167 patients who underwent postoperative volumetric-modulated arctherapy for oral cavity or oropharyngeal cancers were included (60 and 40 % respectively). Two or three dose levels were prescribed (54Gy, 59.4/60Gy±66Gy). Local recurrence occurred in 17 patients (10.2 %). We assessed the patterns of local recurrences according to four methods: 1/ volume-based method using the volume overlap between the recurrence volume and initial target volumes; 2/ volume-based method of overlap between the recurrence volume and the 95 % treatment isodose; 3/ point-based method using the position of the barycentre of the recurrence volume; 4/ combined centroid method classifying recurrences according to both the initial target volumes and dose distribution. Each case was reviewed to make a clinical judgment on these classifications and assessed them as “appropriate”, “possible”, or “inappropriate”. ResultsFor the volume-based method using overlap between the recurrence volume and the initial clinical target volume, this classification was clinically judged as inappropriate in 11 out of 17 cases (65 %). For the volume-based method using overlap between the recurrence volume and the 95 % prescribed isodose, this classification was clinically judged as appropriate in 15 out of 17 cases (88 %). For the point-based method, this classification was clinically judged as appropriate in 14 out of 17 cases (82 %). Thirteen out of 17 local recurrences had the same classification between this point-based method and the volume-based method of overlap between the recurrence volume and the 95 % prescribed isodose. For the combined centroid method, among 17 local recurrences nine were classified as type A, two as type B, two as type C, three as type D and one as type E. This classification was clinically judged as appropriate in 15 out of 17 cases (88 %). Only five out of 17 of the local recurrences were classified the same way according to the four different methods (29 %). ConclusionRecurrences that are “marginal” or “outfield” represent a major challenge for intensity-modulated radiation therapy/volumetric-modulated arctherapy quality assurance and improvement of delineation recommendations. To date, there are no published methods that give complete satisfaction.

Regularity and correlation analysis of regional lymph node metastasis in nonoperative patients with non-small cell lung cancer based on positron emission tomography/computed tomography images

BackgroundDefinitive concurrent chemoradiotherapy (CCRT) is the standard treatment for locally advanced, inoperable non-small cell lung cancer (NSCLC). Previous studies have mainly focused on examining local failure and recurrence patterns after surgery and the principles of lymph node metastasis (LNM) in surgical candidates with NSCLC. However, these studies were just only able to guide postoperative radiotherapy (PORT) and the patterns of LNM in patients with resected NSCLC was inadequate to represent that in locally advanced inoperable NSCLC patients for guiding target volume delineation of CCRT. In this study, we aimed to analyze the metastasis regularities and establish the correlations between different lymph node levels in NSCLC patients without any intervention using positron emission tomography/computed tomography (PET/CT) images.MethodsOverall, 358 patients with N1–N3 NSCLC admitted in our hospital between 2018 and 2022 were retrospectively analyzed. The diagnosis of metastatic lymph nodes was reviewed and determined using the European Organization for Research and Treatment of Cancer standard and the standardized value of the PET/CT examination. Univariate and multivariate analysis were performed to investigate the correlations between the different levels were evaluated by using of the chi-square test and logistic regression model.ResultsThe lymph nodes with the highest metastasis rates in patients with left lung cancer were in order as follows: 10L, 4L, 5, 4R, and 7; while in those with right lung cancer they were 10R, 4R, 7, 2R, and 1R. Notably, we found left lung patients were more likely to have contralateral hilar, mediastinal and supraclavicular lymph nodes involved, and the right lung group exhibited a higher propensity for ipsilateral mediastinum and supraclavicular lymph node invasion. Furthermore, correlation analysis revealed there were significant correlative patterns in the LNM across different levels.ConclusionsThis study elucidated the patterns of primary LNM in patients with NSCLC who had not undergone surgery (without any treatment interventions) and the correlations between lymph node levels. These findings were expected to provide useful reference for target volume delineation in definitive concurrent chemoradiotherapy in locally advanced NSCLC patients.

Clinical target volume design and dose in carbon-ion radiation therapy for sinonasal mucosal melanoma

Background and purposeNo guidelines exist for the clinical target volume (CTV) and radiotherapy dose in sinonasal mucosal melanoma (SNMM). Thus, we aimed to determine the carbon-ion radiotherapy (CIRT) CTV and dose for SNMM. Materials and methodsIn total, 135 patients with SNMM who received CIRT were reviewed. The relative biological effectiveness-weighted dose was 57.6 or 64 Gy in 16 fractions. CTV was classified into small CTV, which included the gross tumor and visible melanosis with a certain margin, and extended CTV, which included the tumor site and adjacent anatomical structures. Local recurrence (LR) patterns were pattern I, II, and III, defined as recurrence over the gross tumor, visible melanosis and subclinical area, which would be covered if extended CTV was applied, and outside the extended CTV, respectively. ResultsThe 5-year LR rate was 35.3 %. The prescribed dose was not a significant risk factor for pattern I LR; however, 57.6 Gy for a large tumor was insufficient for local control. Using an extended CTV was significantly associated with a lower risk of pattern II LR, and these recurrences did not occur in regions that received > 40 Gy. The 5-year pattern III LR rate was 6.4 %. ConclusionUtilizing an extended CTV in CIRT for SNMM is appropriate even for small tumors. Using a smaller CTV after an extended CTV of at least 40 Gy is recommended to reduce adverse events. Although the optimal dose for gross tumors remains unclear, the latest technology with 64 Gy showed good outcomes.

Radiofrequency ablation with or without transarterial chemoembolization for hepatocellular carcinoma meeting Milan criteria: a focus on tumor progression and recurrence patterns.

The aim of this study was to evaluate tumor progression and recurrence patterns of radiofrequency ablation (RFA) with or without transarterial chemoembolization (TACE) for treating hepatocellular carcinoma (HCC) that meets Milan criteria. This retrospective study included consecutive HCC patients meeting Milan criteria who underwent percutaneous RFA with or without TACE as initial treatment at a tertiary academic center between December 2017 and 2022. Technical success rate, local recurrence-free survival (LRFS), progression-free survival (PFS) and recurrence patterns were recorded. A total of 135 HCC patients (109 male [80.7%]) with a mean age of 62 years and 147 target lesions were retrospectively enrolled. The technical success rate was 99.3%. The median LRFS was 60 months, and the cumulative 1-, 3-, and 5-year LRFS were 88.9%, 70.1%, and 30.0%, respectively. Additionally, the median PFS was 23 months, with cumulative 1-, 3-, and 5-year PFS of 74%, 30%, and 0%, respectively. Multivariate analysis confirmed that age > 60, alpha-fetoprotein (AFP) (> 10), and albumin were associated with PFS (2.34, p = 0.004; 1.96, p = 0.021; 0.94, p = 0.007, respectively). Six recurrence patterns were identified: local tumor progression (LTP) alone (n = 15, 25.0%), intrahepatic distant recurrence (IDR) alone (n = 34, 56.7%), extrahepatic recurrence (ER) alone (n = 2, 3.3%), IDR + ER (n = 2, 3.3%), LTP + IDR (n = 5, 8.8%), and LTP + IDR + ER (n = 2, 3.3%). IDR occurred most frequently as a sign of good local treatment. RFA in combination with TACE does not appear to provide an advantage over RFA alone in improving tumor progression in patients with HCC meeting the Milan criteria. However, further prospective studies are needed to confirm these findings and to determine the optimal treatment approach for this patient population.

Impact of pathologic features on local recurrence in penile squamous cell carcinoma after penectomy

BackgroundPenile squamous cell carcinoma (PSCC) is a rare malignancy that may be cured in cases of local disease by resection of the primary tumor. Risk factors and patterns of local recurrence (LR) have not been well described in cases requiring partial or radical penectomy. In this study, we evaluated risk factors for LR and the impact of frozen and final margin assessment. Materials and methodsWe evaluated 119 patients with PSCC who had undergone partial or radical penectomy from 2007 to 2023. Data regarding clinical and pathologic features were collected by retrospective chart review. The primary outcome of interest was LR. Determinants of LR were analyzed by Student's t, Fisher's exact, chi-square and logistic regression analysis. Predictive statistics of frozen margin status on final margin were assessed and LR rates for subsets of frozen and final margin interaction were defined. Finally, all cases of positive margins and LR were described to highlight patterns of LR and the importance of margin status in these cases. ResultsThere were 8 (6.7%) cases of local recurrence. There were no significant predictors of LR, although a trend toward increased LR risk was observed among those with a positive final margin. Positive final margins were found in 15 (13%) cases. Frozen margin analysis was utilized in 79 cases, of which 10 (13%) were positive. The sensitivity, specificity, positive predictive value, and negative predictive value of frozen margin status for final margins were 44%, 92%, 40%, and 93%, respectively. There were no LR among cases in which frozen margin was not sent. Analysis of all cases with positive margin and/or LR identified three subsets of patients: CIS or focally positive margin resulting in either no LR or LR managed with minimal local intervention, bulky disease in which survival is determined by response to subsequent therapy rather than local recurrence, and clinically significant local recurrence requiring continued surveillance and intervention despite negative margins. ConclusionsLR is rare, even in cases of larger, proximal tumors requiring partial or radical penectomy. In this study, no statistically significant risk factors for local recurrence were identified; however, analysis of frozen and final margins provided insight into the importance of margin status and patterns of local recurrence. When feasible, visibly intra-operative negative margins are an excellent predictor of low risk for LR, and, in cases of CIS or focally positive margins, further resection to achieve negative margins is unlikely to reduce the risk of clinically significant LR. Additionally, in cases of bulky disease, the goals of resection should be focused toward palliation and next line therapy.

Focal brachytherapy as definitive treatment for localized prostate cancer: A systematic review and meta-analysis

PURPOSEIn this systematic review and meta-analysis, we describe the oncologic and toxicity outcomes of definitive focal brachytherapy for prostate cancer. METHODS AND MATERIALSA PROSPERO registered study (CRD42023410170) was conducted following the Preferred Reporting Items for Systematic reviews and Meta-analyses (PRISMA) guidelines. PubMed, Embase, and The Cochrane Library were searched for studies between 2000 and 2022. Two authors independently performed the initial search. Biochemical recurrence-free survival (bRFS) was defined as the primary endpoint for the meta-analysis. Generalized linear mixed-effects models were conducted to calculate effect size and quantify heterogeneity. We also describe the side effects and local recurrence patterns of focal brachytherapy. RESULTSTen studies were identified and included 315 patients treated using focal brachytherapy as a definitive treatment. Mean (SD) age was 67.65 (7.9) years and mean (SD) PSA was 7.15 (2.7) ng/mL. Most patients (n = 236, 75%) underwent LDR Brachytherapy and 25% received HDR brachytherapy. Among the participants, 147 (46.5%) had a Gleason score ≤6, and 169 (53.5%) had a Gleason score ≥7. Only 11 (3.5%) patients received ADT. Overall, bRFS rate at median follow-up 4 years (Range: 1–6.42 years) was 91% (95% confidence interval [CI], 82–95%). Acute Grade ≤ 2 GU and GI toxicities were reported in 22 (7%) and 11 (3.5%) patients, respectively. Late Grade ≤ 2 GU and GI toxicity were reported in 6 (2%) and 14 (4.4%) patients, respectively. One case of prostate hemorrhage due to improper foley removal was noted but otherwise no acute or late Grade 3 or higher GI or GU toxicity related to radiotherapy was reported. CONCLUSIONOverall, definitive focal brachytherapy has a favorable toxicity profile. Oncologic outcomes are yet to mature. The evidence is limited by the small number of studies with low patients’ number, across study heterogeneity, and possibility of publication bias.

Clinical Outcomes Among Patients Treated With Stereotactic Body Radiation Therapy to Femur Metastases for Oligometastatic Disease Control or Reirradiation: Results From a Large Single-Institution Experience

There are limited data regarding outcomes after stereotactic body radiation therapy (SBRT) for femur metastases, which was an exclusion criteria for the Stereotactic Ablative Radiotherapy for the Comprehensive Treatment of Oligometastatic Cancers (SABR-COMET) trial. We aimed to characterize clinical outcomes from a large single institution experience. Forty-eight patients with 53 lesions were consecutively treated with femur SBRT from May 2017 to June 2022. The Kaplan-Meier method and Cox proportional hazard models were used to characterize time-to-event endpoints and associations between baseline factors and clinical outcomes, respectively. Local control and locoregional control were defined as the absence of tumor progression within the radiation treatment field or within the treated femur, respectively. Most patients had Eastern Cooperative Oncology Group performance status 0 to 1 (90%), prostate (52%) or breast/lung (17%) cancer, and 1 to 3 lesions (100%), including 29 proximal and 5 distal. Fifty-seven percent of the lesions were treated with concurrent systemic therapy. Median planning target volume was 49.1 cc (range, 6.6-387 cc). Planning target volume V100 (%) was 99% (range, 90-100). Fractionation included 18 to 20 Gy/1F, 27 to 30 Gy/3F, and 28.5-40 Gy/5F. Forty-two percent had Mirels score ≥7 and most (94%) did not have extraosseous extension. Acute toxicities included grade 1 fatigue (15%), pain flare (7.5%), nausea (3.8%), and decreased blood counts (1.9%). Late toxicities included fracture (1.9%) at 1.5 years and osteonecrosis (4%) from dose of 40 Gy in 5F and 30 Gy in 5F (after prior 30 Gy/10F). One patient (2%) required fixation postradiation for progressive pain. With median follow-up 19.4 months, 1- and 2-year rates of local control were 94% and 89%, locoregional control was 83% and 67%, progression-free survival were 56% and 25%, and overall survival were 91% and 73%. Fifty percent of local regional recurrence events occurred within 5 cm of gross tumor volume. Femur SBRT for oligometastatic disease control in well-selected patients was associated with good outcomes with minimal rates of acute and late toxicity. Patterns of local regional recurrence warrant consideration of larger elective volume coverage. Additional prospective study is needed.

Anatomical changes in resection cavity during brain radiotherapy.

Brain tumors are in general treated with a maximal safe resection followed by radiotherapy of remaining tumor including the resection cavity (RC) and chemotherapy. Anatomical changes of the RC during radiotherapy can have impact on the coverage of the target volume. The aim of the current study was to quantify the potential changes of the RC and to identify risk factors for RC changes. Sixteen patients treated with pencil beam scanning proton therapy between October 2019 and April 2020 were retrospectively analyzed. The RC was delineated on pre-treatment computed tomography (CT) and magnetic resonance imaging, and weekly CT-scans during treatment. Isotropic expansions were applied to the pre-treatment RC (1-5mm). The percentage of volume of the RC during treatment within the expanded pre-treatment volumes was quantified. Potential risk factors (volume of RC, time interval surgery-radiotherapy and relationship of RC to the ventricles) were evaluated using Spearman's rank correlation coefficient. The average variation in relative RC volume during treatment was 26.1% (SD 34.6%). An expansion of 4mm was required to cover > 95% of the RC volume in > 90% of patients. There was a significant relationship between the absolute volume of the pre-treatment RC and the volume changes during treatment (Spearman's ρ = -0.644; p = 0.007). RCs are dynamic after surgery. Potentially, an additional margin in brain cancer patients with an RC should be considered, to avoid insufficient target coverage. Future research on local recurrence patterns is recommended.

NCOG-40. PATTERNS OF PROGRESSION IN PATIENTS WITH NEWLY DIAGNOSED PRIMARY CENTRAL NERVOUS SYSTEM LYMPHOMA FOLLOWING TREATMENT WITH HIGH-DOSE METHOTREXATE

Abstract INTRODUCTION Primary central nervous system lymphoma (PCNSL) is a rare form of non-Hodgkin's lymphoma that primarily affects the brain. Recurrence of PCNSL within the central nervous system is common, but patterns of intracranial recurrence following induction chemotherapy have not been extensively studied. This study aims to elucidate the patterns of recurrence and progression in PCNSL. METHODS Adult patients from two institutions with newly diagnosed PCNSL that received HD-MTX based chemotherapy from 2011-2023 were included. Patient charts and diagnostic imaging were retrospectively reviewed. The pattern of recurrence/progression was reviewed by comparing the initial diagnostic MRI to the first recurrence MRI (T1 post-contrast and FLAIR sequence). Distant recurrences were defined as separate lesions from the previous primary enhancing lesion, located outside the initial FLAIR abnormality observed on imaging. Local recurrences were characterized as new lesions overlapping with the primary enhancing lesion/FLAIR abnormality. RESULTS 25 patients were identified to have been diagnosed with PCNSL and progressed through initial definitive treatment with HD-MTX based chemotherapy. 2/25 received initial management with radiation therapy. Median age at diagnosis was 66 years. The median time to progression was 18.1 months (Range; 0.9-70). Twelve of the 25 patients had a complete response to initial systemic therapy, 6 had a partial response, and 7 patients had disease progression through chemotherapy. Eleven of the 25 patients were found to have multifocal disease at diagnosis. 13/25 (52%) patients had distant recurrence only, 5/25(20%) had only local recurrence, and 7/25 (28%) displayed both local and distant recurrence pattern. CONCLUSION In this retrospective review, for patients diagnosed with PCNSL who are able to undergo HD-MTX we identified that the majority of disease recurrence is outside or distant to the primary disease site vs locally (80% vs 20%). Such findings should be verified with a larger cohort and can help direct further consolidation strategies.

Predictors and outcomes of recurrent retroperitoneal liposarcoma: new insights into its recurrence patterns

BackgroundThe clinical profiles of recurrent retroperitoneal liposarcoma (RLS) need to be explored. The recurrence patterns of RLS are controversial and ambiguous.MethodsA total of 138 patients with recurrent RLS were finally recruited in the study. The analysis of overall survival (OS) and recurrence-free survival (RFS) was performed by Kaplan‒Meier analysis. To identify independent prognostic factors, all significant variables on univariate Cox regression analysis (P ≤ 0.05) were subjected to multivariate Cox regression analysis. The corresponding nomogram model was further built to predict the survival status of patients.ResultsAmong patients, the 1-, 3-, and 5-year OS rates were 70.7%, 35.9% and 30.9%, respectively. The 1-, 3- and 5-year RFS rates of the 55 patients who underwent R0 resection were 76.1%, 50.8% and 34.4%, respectively. The multivariate analysis revealed that resection method, tumor size, status of pathological differentiation, pathological subtypes and recurrence pattern were independent risk factors for OS or RFS. Patients with distant recurrence (DR) pattern usually had multifocal tumors (90.5% vs. 74.7%, P < 0.05); they were prone to experience changes of pathological differentiation (69.9% vs. 33.3%, P < 0.05) and had a better prognosis than those with local recurrence (LR) pattern. R0 resection and combined organ resection favored the survival of patients with DR pattern in some cases.ConclusionsPatients with DR pattern had better prognosis, and they may benefit more from aggressive combined resection than those with LR pattern. Classifying the recurrence patterns of RLS provides guidance for individualized clinical management of recurrent RLS.

Patterns of Local Recurrence and Risk of Skin Recurrence in Soft Tissue Sarcomas After Surgical Resection

Although there is a theoretical risk of skin seeding during surgical resection of soft tissue sarcomas (STSs), current consensus guidelines recommend against routine use of bolus during radiation therapy (RT). However, the risk of skin recurrence has not been systematically assessed. We aimed to assess the patterns of local recurrence (LR) in patients with STS treated with surgery with or without RT. We performed a retrospective analysis of adults with STSs evaluated at our institution between 2007 and 2021. For patients who developed LR, the depth was evaluated. Progression-free survival and overall survival were analyzed from time of first LR using the Kaplan-Meier method. Cumulative incidence of distant metastasis was calculated with competing risk analysis from date of LR. Of the 206 patients evaluated, 20 had LR (9.7%). Among patients with LR, 5 patients (25.0%) were treated with surgery alone and 15 patients (75.0%) with surgery and RT. In patients treated with RT, 46.7% had preoperative RT, 53.3% had postoperative RT, and bolus was used in 46.7%. Surgical margins were close (<1 mm) in 4 patients (20.0%) and positive in 10 patients (50.0%). LR occurred in the deep subfascial tissue in 9 patients (45%), subcutaneous tissue in 10 patients (50.0%), and skin in 1 patient (5.0%). The patient with a skin recurrence was treated with surgery alone, and the tumor involved the skin at presentation. In patients treated with RT, LR occurred within the RT field in 13 patients (86.7%). At 1 year after LR, progression-free survival was 70.3%, overall survival was 81.7%, and cumulative incidence of distant metastasis was 5.9%. Skin recurrences were rare after surgical resection of STSs and only occurred in a tumor that involved the skin at initial presentation. These findings support current recommendations against routine use of bolus in STSs not involving the skin at presentation.

Patterns of local recurrence and risk of skin recurrence in soft tissue sarcomas after surgical resection.

Soft tissue sarcomas (STSs) are rare, heterogeneous tumors primarily managed surgically with radiotherapy (RT) added to improve local control. Although there is a theoretical risk of skin seeding at the time of surgery, current ASTRO Clinical Practice Guidelines recommend against routine use of bolus during pre-operative or post-operative radiotherapy for STS due to increased risk of skin toxicity without clear benefit. However, in the modern era with contemporary treatment planning techniques, the risk of skin recurrence has not been assessed. We performed a detailed analysis of the patterns of local recurrence (LR) in patients with STS treated with surgical resection with or without RT. We performed a retrospective analysis of 206 adult patients with extremity or trunk STSs evaluated in the Department of Radiation Oncology at our institution over 14 years (2007-2021) and identified all patients with LR. The depth of the recurrence and location relative to the radiation field in patients treated with radiotherapy was evaluated. Progression free survival (PFS) and overall survival (OS) were analyzed using the Kaplan-Meier method, and cumulative incidence of distant metastasis (CIDM) was calculated with competing risk analysis from the date of LR. Of the 206 patients evaluated, 20 experienced a LR after surgical resection with or without RT. Among patients with a LR, 5 patients (25.0%) were treated with surgery alone and 15 patients (75.0%) received surgery and RT. In patients treated with RT, 46.7% had pre-operative RT, 53.3% had post operative RT, and bolus was used in 5 patients (33.3%). Surgical margins were close (<1mm) in 4 patients (20.0%) and positive in 10 patients (50.0%). Tumor grade was intermediate/high in 15 patients (75%) and the median tumor size was 9 cm (range 5-12). LR occurred in the muscle in 8 patients (40%), subcutaneous tissue in 11 patients (55.0%), and skin in 1 patient (5.0%). The patient with a skin recurrence was treated with surgery alone and the tumor involved the skin at presentation. In the patients treated with RT, LR occurred within radiation field in 10 patients (66.7%). Median follow up time after local recurrence was 12.9 months. At 3 years after LR, PFS was 43.9%, OS was 81.7%, and CIDM was 16.7%. Skin recurrences were exceedingly rare after surgical resection of STSs, and only occurred in a tumor that involved the skin at initial presentation. Due to the increased dose to the normal skin and subcutaneous tissues when bolus is used, which increases risk of toxicity, these findings support current recommendations against routine use of bolus in STSs not involving the skin at presentation.

Oncological recurrence following pathological complete response after neoadjuvant treatment in patients with esophageal cancer — a retrospective cohort study

BackgroundTo evaluate recurrence in patients with post-neoadjuvant pathological complete response (pCR) and in patients with complete response of primary tumor but persisting lymphatic spread of disease (non-pCR, ypT0ypN +) of esophageal cancer.MethodsSeventy-five patients (63 pCR, 12 non-pCR) were analyzed retrospectively. Pattern and incidence of local and distant recurrence as well as the impact on overall (OS) and disease-free survival (DFS) were evaluated. The efficacy of neoadjuvant chemotherapy according to FLOT protocol was compared to neoadjuvant chemoradiation according to CROSS protocol.ResultsIn the pCR group, isolated local recurrence was diagnosed in 3%, while no isolated local recurrence was observed in the non-pCR group due to the high incidence of distant recurrence. Distant recurrence was most common in both cohorts (isolated distant recurrence: pCR group 10% to non-pCR group 55%; simultaneous distant and local recurrence: pCR group 3% to non-pCR group 18%). Median time to distant recurrence was 5.5 months, and median time to local recurrence was 8.0 months. Cumulative incidence of distant recurrence (with and without simultaneous local recurrence) was 16% (± 6%) in pCR patients and 79% (± 13%) in non-pCR patients (hazard ratio (HR) 0.123) estimated by Kaplan–Meier method. OS (HR 0.231) and DFS (HR 0.226) were significantly improved in patients with pCR compared to patients with non-pCR. Advantages for FLOT protocol compared to CROSS protocol, especially with regard to distant control of disease (HR 0.278), were observed (OS (HR 0.361), DFS (HR 0.226)).ConclusionDistant recurrence is the predominant site of treatment failure in patients with pCR and non-pCR grade 1a regression, whereby recurrence rates are much higher in patients with non-pCR.

Predictors and outcomes of recurrent retroperitoneal liposarcoma with multiple tumors.

Retroperitoneal liposarcoma (RLS) is a rare but severe disease. Repeated postoperative recurrence with multiple tumors is a therapeutic dilemma. The clinical outcomes and survival predictors of recurrent RLS with multiple tumors remain to be explored. Patients with recurrent RLS were retrospectively analyzed. Univariate and multivariate analysis was performed to find independent prognostic factors that were correlated with Overall survival (OS) or progression-free survival (PFS). Factors significant in univariate analysis were further included into multivariate Cox proportional hazards regression model. The nomogram model was built to predict the survival status of patients. Variables that were significant in multivariable analysis were added to the internally validated nomogram models. The analysis of OS and PFS was performed by Kaplan-Meier analysis and log-rank test. A total of 113 recurrent RLS patients with multiple tumors were enrolled in the study. The 1-, 3-, and 5-years OS (PFS) rates were 70.7% (76.1%), 35.9% (76.1%), and 30.9% (76.1%), respectively. Univariate and multivariate analyses showed that number of surgeries, resection methods, tumor size, status of pathological differentiation, pathological subtypes, and recurrence patterns were important prognostic factors for OS or PFS (each p < 0.05). Nomogram models were established to efficiently predict the prognostic status of patients. Patients with the local recurrence (LR) pattern had a poor prognosis and would derive no survival benefit from combined organ resection and R0/R1 resection (each p < 0.05). RLS patients recurrence with multiple tumors had a poor prognosis. Those patients should be followed up more frequently after surgery. The strategies of aggressive resection may not improve the survival of patients with LR pattern in the retroperitoneum. Prognostic factors in the efficient nomogram models should be considered in the individualized clinical management of recurrent RLS with multiple tumors.

Development of Prostate Bed Delineation Consensus Guidelines for Magnetic Resonance Image-Guided Radiotherapy and Assessment of Its Effect on Interobserver Variability

Background and purposeThe use of MRI in radiotherapy planning is becoming more widespread, particularly with the emergence of MRI-guided radiotherapy (MRIgRT) systems. Existing guidelines for defining the prostate bed clinical target volume (CTV) show considerable heterogeneity. This study aims to establish baseline interobserver variability (IOV) for prostate bed CTV contouring on MRI, develop international consensus guidelines and evaluate its effect on IOV. Methods and MaterialsParticipants delineated the CTV on three MRI scans, obtained from the xxx xxx MR-Linac, as per their normal practice. Radiation oncologist contours were visually examined for discrepancies and interobserver comparisons were evaluated against Simultaneous Truth and Performance Level Estimate (STAPLE) contours using overlap metrics (Dice similarity coefficient and Cohen's Kappa), distance metrics (mean distance to agreement and Hausdorff distance) and volume measurements.. A literature review of post-radical prostatectomy local recurrence patterns was performed and presented alongside IOV results to the participants. Consensus guidelines were collectively constructed and IOV assessment was repeated using these guidelines. ResultsSixteen radiation oncologists’ contours were included in the final analysis. Visual evaluation demonstrated significant differences in the superior, inferior and anterior borders. Baseline IOV assessment indicated moderate agreement for the overlap metrics whilst volume and distance metrics demonstrated greater variability. Consensus for optimal prostate bed CTV boundaries was established during a virtual meeting. Post-guideline development, a decrease in IOV was observed. The maximum volume ratio decreased from 4.7 to 3.1 and volume coefficient of variation reduced from 40% to 34%. The mean Dice similarity coefficient rose from 0.72 to 0.75 and the mean distance to agreement decreased from 3.63mm to 2.95mm. ConclusionsInterobserver variability in prostate bed contouring exists amongst international genitourinary experts, although this is lower than previously reported. Consensus guidelines for MRI-based prostate bed contouring have been developed and this has resulted in an improvement in contouring concordance. However, IOV persists and strategies such as an education program, development of a contouring atlas and further refinement of the guidelines may lead to additional improvements.

Local Recurrences in Rectal Cancer: MRI vs. CT

Rectal cancers are often considered a distinct disease from colon cancers as their survival and management are different. Particularly, the risk for local recurrence (LR) is greater than in colon cancer. There are many factors predisposing to LR such as postoperative histopathological features or the mesorectal plane of surgical resection. In addition, the pattern of LR in rectal cancer has a prognostic significance and an important role in the choice of operative approach and. Therefore, an optimal follow up based on imaging is critical in rectal cancer. The aim of this review is to analyse the risk and the pattern of local recurrences in rectal cancer and to provide an overview of the role of imaging in early detection of LRs. We performed a literature review of studies published on Web of Science and MEDLINE up to January 2023. We also reviewed the current guidelines of National Comprehensive Cancer Network (NCCN) and the European Society for Medical Oncology (ESMO). Although the timing and the modality of follow-up is not yet established, the guidelines usually recommend a time frame of 5 years post surgical resection of the rectum. Computed Tomography (CT) scans and/or Magnetic Resonance Imaging (MRI) are the main imaging techniques recommended in the follow-up of these patients. PET-CT is not recommended by guidelines during post-operative surveillance and it is generally used for problem solving.

Retrospective analysis of local recurrence pattern by computed tomography image-guided intracavitary and interstitial brachytherapy for locally advanced cervical cancer in a single Japanese institution

PURPOSEThe purpose of this study was to investigate the treatment results with focus on local control (LC) by computed tomography (CT)-guided intracavity brachytherapy and interstitial brachytherapy (ICBT/ISBT) for locally advanced cervical cancer (LACC). METHODS AND MATERIALSPatients with LACC undergoing ICBT/ISBT at least once in our institution between January 2017 and June 2019 were analyzed retrospectively. The primary endpoint was local control (LC), and the secondary endpoints were progression-free survival (PFS), overall survival (OS), and late toxicities. Differences between patient subgroups for prognostic factors in LC, PFS, and OS were analyzed using the log-rank test. The recurrence patterns of LC were also investigated. RESULTSForty-four patients were included in the present study. The median high-risk clinical target volume (HR-CTV) at the initial brachytherapy was 48.2 cc. The median total dose of HR-CTV D90 (EQD2) was 70.7 Gy. The median followup period was 39.4 months. The 3-year LC, PFS and OS rates in all patients were 88.2%, 56.6%, and 65.4% (95% CI 50.3–78.0%), respectively. Corpus invasion and large HR-CTV (70 cc or more) were significant prognostic factors in LC, PFS, and OS. Marginal recurrences at the fundus of the uterus were detected in 3 of 5 patients in whom local recurrence was observed. Late toxicities of Grade 3 or higher were detected in 3 patients (6.8%). CONCLUSIONSFavorable LC was achieved by performing CT-guided ICBT/ISBT for LACC. The brachytherapy strategy for patients with corpus invasion or large HR-CTV may need to be reconsidered.

Patterns of Failure in High-Grade Soft Tissue Sarcomas of the Extremities and Trunk Wall After Pre- or Postoperative Radiation Therapy

Radiotherapy (RT) is a mainstay of treatment for high-grade soft tissue sarcomas (STS). We sought to examine the pattern of local recurrence (LR) with regard to target volume, clinical course, and tumor characteristics in extremity and trunk wall STS patients receiving pre- or postoperative RT. In this retrospective study, LR rates and patterns in 91 adult patients with a primary diagnosis of localized high-grade STS of the extremities and trunk wall treated with pre- or postoperative RT at our institution between 2004 and 2021 were analyzed. Radiation treatment plans and imaging data sets at diagnosis and LR were compared. Seventeen out of 91 (18.7 %) patients developed a LR after a median time of 12.7 months. In 10 out of 13 LRs (76.9%) with available treatment plans and radiographic imaging data at the time of recurrence, the LR occurred within the planned target volume (PTV), 2 LRs were marginal (15.4%, at the edge of the PTV volume), and one relapsed out-of-field (7.7%, outside the PTV volume). Positive surgical margins (microscopic or macroscopic) were found in 5 out of 91 patients (5.5%), 1 of which was found in the 17 patients with LRs (5.9%). Eleven of 13 LR patients (84.6%) with available treatment plans and radiographic imaging data received postoperative RT; the median total RT dose was 60 Gy. Volumetric-modulated arc therapy was used in 10 (76.9%), intensity-modulated RT in 2 (15.4%), and 3-dimensional conformal radiation therapy in 1 (7.7%) of 13 LRs. The majority of LRs occurred within the PTV suggesting that LR is most likely not a consequence of inadequate target volume definition, but rather of radioresistant tumor biology. To further improve local tumor control, future research on the potential of dose escalation with normal tissue sparing, STS subtype-specific tumor biology, radiosensitivity, and surgical technique is indicated.

Does minimally invasive surgery have a different impact on recurrence and overall survival in patients with pancreatic head versus body/tail cancer?

This study sought to investigate the impact of minimally invasive surgery (MIS) on recurrence and overall survival between patients with pancreatic head versus body/tail cancers. The risk factors associated with recurrence and long-term outcomes were analyzed according to tumor location and operative modality. A total of 288 and 87 patients underwent surgical resection for pancreatic head cancer and body/tail cancer, respectively. The perioperative outcomes and histopathologic results were comparable in open and MIS approach in both head and body/tail groups. There was no difference in local or systemic recurrence patterns and disease-free and overall survival rates according to primary tumor location and surgical modality. During subgroup analysis by stage; however, patients with stage III pancreatic head cancer in the MIS group had a decreased disease-free survival compared with those in the open surgery group (p = 0.020). On multivariate analysis, MIS was not a risk factor of total or local recurrences. Recurrence patterns and overall survival rates of patients did not differ according to tumor location and surgical approach. However, patients with stage III pancreatic head cancer in the MIS group showed inferior disease-free survival relative to patients who underwent open surgery.