A Precise Approach for Radiotherapy of Breast Cancer.

Radiotherapy is an integral part of the multidisciplinary management of breast cancer (BC). There have been multiple recent advances in the delivery of radiotherapy, reviewed with a critical discussion of the evidence from trials investigating adjuvant ultra-hypofractionation and partial breast irradiation for early-stage BC, and the locoregional management of lymph nodes in locally advanced BC. Multiple precision medicine-based approaches have been developed as prognostic and/or predictive for BC patients and identifying biomarkers of radioresistance could help identify patients that may benefit from dose-escalated radiotherapy or radiosensitizers. Radiotherapy after breast reconstruction is an area of current controversy in the field, and we evaluated the decision-making considerations in this situation. The oligometastatic state is an emerging field for many cancer sites based on recent trials investigating ablative radiotherapy for oligometastatic BC. This chapter is an overview of radiotherapy for BC, with a focus on recent advances in early-stage, locally advanced, and oligometastatic disease.

A systematic review of transition readiness and transfer satisfaction measures for adolescents with chronic illness.

BACKGROUND: The transition from pediatric to adult health care can be challenging for adolescents with chronic illnesses. As a result, many adolescents are unable to transfer to adult health care successfully. Adequate measurement of transition readiness and transfer satisfaction with disease management is necessary in order to determine areas to target for intervention towards improving transfer outcomes. OBJECTIVES: This study aims to systematically review and critically appraise research on transition readiness and transfer satisfaction measures for adolescents with chronic illnesses as well as to assess the psychometric quality of these measures. METHODS: Electronic searches were conducted in MEDLINE, EMBASE, CINAHL, PsychINFO, ERIC, and ISI Web of Knowledge for transition readiness and transfer satisfaction measures for adolescents with chronic health conditions. Two reviewers independently selected articles for review and assessed methodological quality. RESULTS: In all, eight readiness and six satisfaction measures met the inclusion criteria, for a total of 14 studies, which were included in the final analysis. None of these measures have well-established evidence of reliability and validity. Most of the measures were developed ad hoc by the study investigators, with minimal to no evidence of reliability and/or validity using the Cohen criteria and COSMIN checklist. CONCLUSION: This research indicates a major gap in our knowledge of transitional care in this population, because there is currently no well-validated questionnaire that measures readiness for transfer to adult health care. Future research must focus on the development of well-validated transition readiness questionnaires, the validation of existing measures, and reaching consensus on outcomes of successful transfer.

Analysis of multicatheter interstitial brachytherapy: Accelerated partial breast irradiation in a retrospective cohort of early-stage breast cancer patients.

PURPOSE: To determine cardiac dose received by patients treated with high dose rate interstitial brachytherapy. Patients with early-stage, node negative breast cancer can be treated using multi-catheter interstitial brachytherapy accelerated partial breast irradiation (MIB-APBI), with the benefit of reduced treatment volumes and favorable toxicity. METHODS AND MATERIALS: We conducted a retrospective review of left-sided breast cancer patients treated using MIB-APBI at our institution since 2014. The mean heart dose (MHD) was calculated using the Oncentra 3.2 planning system. The minimum distance between the planning target volume (PTVeval) and heart contour was measured manually. FINDINGS: 81 patients were included. The upper outer quadrant was the most common site. The MHD was 97.8 cGy (EQD2a/b=2) (range 22-229 cGy). MHD significantly correlated with the closest distance between PTVeval and heart contour (correlation coefficient -0.823, p <0.001); size of PTVeval (cc) and quadrant location did not. CONCLUSIONS: Appropriately selected women with early-stage, low-risk, left-sided breast cancer who received MIB-APBI had acceptable MHD. There was a strong correlation between the distance of PTVeval and MHD. Quadrant breast tumor is in cannot be used as a surrogate for MHD in brachytherapy. Our findings contribute to the growing evidence of the utility and safety of MIB-APBI.

Patterns of failure with 18F-DCFPyL PSMA-PET/CT in the post-prostatectomy setting: A regional cohort analysis.

INTRODUCTION: This study aimed to assess the detection rate of prostate cancer recurrence by prostate-specific member antigen positron emission tomography/computed tomography (PSMA PET/CT) with 18F-DCFPyL in patients with residual disease or biochemical recurrence (BCR), and its association with surgical pathology and prostate-specific antigen (PSA) kinetics. METHODS: Men from South Central Ontario enrolled in the PSMA Registry for Recurrent Prostate cancer (PREP) between April 2019 and December 2021 after radical prostatectomy (RP) and who had 1) pathologic stage N1 or persistent elevated PSA; or 2) BCR (PSA >0.10 ng/mL) where initial postoperative PSA was undetectable were included. RESULTS: A total of 169 men (median age 68 years; interquartile range [IQR] 62-71) with complete data met the above criteria. The median PSA was 0.27 ng/mL (IQR 0.16-0.85) prior to PSMA-PET. Overall positivity rate 59%; when PSA was <0.40 ng/mL, overall positivity rate 42% vs. 85% with PSA ≥0.40 ng/mL (p<0.001). Higher pathologic tumor stage increased detection of regional lymph nodes (LN) (pT2-3a: 32% vs. pT3b: 69%, p<0.001) but not distant metastases (pT2-3a: 12% vs. pT3b: 24%, p=0.15). PSMA-PET detected 18% with prostate bed, 42% with regional LN disease, and 44% with pelvic-only disease. The three most involved LN chains were the internal (21%) and external (20%) iliac, and obturator chains (16%). CONCLUSIONS: This prospective study of patients with residual disease or BCR after RP illustrates patterns of failure that could impact diagnosis and postoperative management. Such patients have significant risk of regional LN positivity on PSMA-PET highlighting a need to include pelvic LN within salvage radiotherapy volumes.

One Fraction Size Does Not Fit All: Patient Preferences for Hypofractionated Radiation Therapy From a Discrete Choice Experiment.

PURPOSE: Hypofractionated external beam radiation therapy (EBRT) is a standard of care option for localized prostate cancer. To inform clinical practice we quantified patients' preferences for convenience, efficacy, and toxicity risks, of conventional, moderate hypofractionation, and stereotactic radiation therapy regimens. METHODS AND MATERIALS: We used a discrete choice experiment with a voluntary sample consisting of patients treated with EBRT for localized prostate cancer at our academic cancer center. In 2019, 58 participants, mean (SD) age of 72.9 (7.1) years, agreed to complete an in-person 1:1 discrete choice experiment. Each participant made 12 choices between 2 unique EBRT scenarios, each described by 5 attributes: (1) treatment time; (2) fiducial markers; and risk of (3) prostate specific antigen recurrence; (4) acute and (5) late GI or GU toxicity. Patient preferences were estimated using mixed multinomial logistic regression, and prespecified subgroups with conditional logistic regression. RESULTS: All attributes were statistically significant, thus influenced participants' choices. Risks of prostate specific antigen recurrence (ß = -2.581), late (ß = -1.854), and acute (ß = -1.005) toxicity were most important to participants (P < .001 for each), followed by EBRT length (ß = -0.728; P = .017) and fiducial marker implantation (ß = -0.563; P = .004). Older (ß = -0.063; 95% confidence interval, -0.12, -0.01) and rural (ß = -0.083; 95% CI -0.14, -0.02) participants significantly preferred shorter EBRT and were less willing-to-extend treatment to reduce toxicity risk. CONCLUSIONS: Patients with prostate cancer place importance on EBRT attributes, and some are willing to trade-off increased risk of toxicity for improved convenience. Our findings promote shared clinical decision-making because patients are interested in learning about the trade-offs involved.

Adjuvant Radiotherapy for Upper Tract Urothelial Carcinoma: Systematic Review and Meta-Analysis.

PURPOSE: Upper tract urothelial carcinoma (UTUC) is a rare form of malignancy comprising only 5% of urothelial cancers. The mainstay of treatment is radical nephroureterectomy (RNU) with bladder cuff excision. Neoadjuvant or adjuvant chemotherapy is often used in locally advanced disease. The role of adjuvant radiotherapy (RT), however, remains controversial. To further explore the potential role of adjuvant RT, we performed a systematic review and meta-analysis of the literature from 1990 to present. METHODS AND MATERIALS: We identified 810 candidate articles from database searches, of which 67 studies underwent full-text review, with final inclusion of 20 eligible studies. Among the included studies, there were no randomized controlled trials and a single prospective trial, with the remainder being retrospective series. We performed quantitative synthesis of the results by calculating the pooled odds ratios (OR) for the primary outcome of locoregional recurrence (LRR) and secondary outcomes of overall survival (OS), cancer-specific survival (CSS) and distant recurrence (DR). RESULTS: Adjuvant RT, which was mostly prescribed for locally advanced or margin-positive disease following RNU, significantly reduced locoregional recurrence risk OR 0.43 (95% CI: 0.23-0.70), and the effect remained significant even following subgroup analysis to account for adjuvant systemic therapy. The effect of adjuvant RT on 3-year OS, 5-year CSS and DR was non-significant. However, 5-year OS was unfavourable in the adjuvant RT arm, but study heterogeneity was high, and analysis of small-study effects and subgroups suggested bias in reporting of outcomes. CONCLUSIONS: Adjuvant RT in the setting of locally advanced UTUC improves locoregional control following definitive surgery, but does not appear to improve OS. Higher-quality studies, ideally randomized controlled trials, are needed to further quantify its benefit in this setting, and to explore multi-modal treatments that include systemic agents given concomitantly or sequentially with RT, which may offer an OS benefit in addition to the locoregional control benefit of RT.

The therapeutic relevance of a BRCA2 mutation in a patient with recurrent thymoma: a case report.

Background: Thymomas are characterized by a low tumor mutation burden and a paucity of actionable mutations. Clinical behavior can vary from relatively indolent to very aggressive and impact survival. Platinum-based chemotherapy is the primary treatment modality for inoperable disease and is palliative in intent. Patients with advanced thymoma frequently experience disease recurrence after frontline therapy. Treatment options for relapsed thymoma are relatively limited. A case of recurrent thymoma harboring a breast cancer gene 2 (BRCA2) mutation was presented for multidisciplinary discussion at the International Thymic Malignancy Interest Group (ITMIG) Tumor Board meeting. Case Description: A 63-year-old female presented with Tumor Node Metastasis (TNM) stage I, World Health Organization (WHO) subtype B1 thymoma at diagnosis and underwent surgical resection. First recurrence occurred in the left costophrenic recess and was treated with preoperative external beam radiotherapy (EBRT), surgical excision, and post-operative chemotherapy. Histology was consistent with WHO subtype B2 thymoma and genomic analysis of the resected tumor detected a BRCA2 mutation. Second recurrence occurred in the mediastinum and bilateral pleurae. Mediastinal disease was treated with EBRT, and the pleural deposits were observed initially. However, upon further progression, the case was discussed at the ITMIG tumor board meeting to determine optimal second line therapy for this patient. Conclusions: A potential role of poly (ADP-ribose) polymerase (PARP) inhibitors versus cytotoxic chemotherapy for treatment of BRCA2-mutated recurrent thymoma merits discussion. However, due to the absence of data to support the functional and therapeutic significance of BRCA2 mutations in patients with thymoma, the potential for severe toxicity associated with PARP inhibitors, and availability of other safe and effective alternatives, other treatment options should be considered. PARP inhibitors can be considered for treatment of BRCA2-mutated thymomas as part of a clinical trial or when other treatment options have been exhausted.

A Comparison of Hypofractionated and Twice-Daily Thoracic Irradiation in Limited-Stage Small-Cell Lung Cancer: An Overlap-Weighted Analysis.

Despite evidence for the superiority of twice-daily (BID) radiotherapy schedules, their utilization in practice remains logistically challenging. Hypofractionation (HFRT) is a commonly implemented alternative. We aim to compare the outcomes and toxicities in limited-stage small-cell lung cancer (LS-SCLC) patients treated with hypofractionated versus BID schedules. A bi-institutional retrospective cohort review was conducted of LS-SCLC patients treated with BID (45 Gy/30 fractions) or HFRT (40 Gy/15 fractions) schedules from 2007 to 2019. Overlap weighting using propensity scores was performed to balance observed covariates between the two radiotherapy schedule groups. Effect estimates of radiotherapy schedule on overall survival (OS), locoregional recurrence (LRR) risk, thoracic response, any ≥grade 3 (including lung, and esophageal) toxicity were determined using multivariable regression modelling. A total of 173 patients were included in the overlap-weighted analysis, with 110 patients having received BID treatment, and 63 treated by HFRT. The median follow-up was 20.4 months. Multivariable regression modelling did not reveal any significant differences in OS (hazard ratio [HR] 1.67, p = 0.38), LRR risk (HR 1.48, p = 0.38), thoracic response (odds ratio [OR] 0.23, p = 0.21), any ≥grade 3+ toxicity (OR 1.67, p = 0.33), ≥grade 3 pneumonitis (OR 1.14, p = 0.84), or ≥grade 3 esophagitis (OR 1.41, p = 0.62). HFRT, in comparison to BID radiotherapy schedules, does not appear to result in significantly different survival, locoregional control, or toxicity outcomes.

Case presentations and recommendations from the 2018 ITMIG Annual Meeting.

The 9th International Thymic Malignancy Interest Group's (ITMIG) Annual Meeting was held in Seoul, South Korea in October 2018, and in this article, we discuss three of the cases presented and review the radiology imaging and pathology slides. The first two cases involve thymic carcinoma: the first reviews systemic therapy recommendations for non-resectable recurrence and the second case the optimal treatment recommendations after incomplete resection. The third case discusses treatment recommendations for recurrent thymoma after complete resection.

Distribution of Mediastinal Lesions Across Multi-Institutional, International, Radiology Databases.

INTRODUCTION: Mediastinal lesions are uncommon; studies on their distribution are, in general, small and from a single institution. Furthermore, these studies are usually based on pathology or surgical databases and, therefore, miss many lesions that did not undergo biopsy or resection. Our aim was to identify the distribution of lesions in the mediastinum in a large international, multi-institutional cohort. METHODS: At each participating institution, a standardized retrospective radiology database search was performed for interpretations of computed tomography, positron emission tomography-computed tomography, and magnetic resonance imaging scans including any of the following terms: "mediastinal nodule," "mediastinal lesion," "mediastinal mass," or "mediastinal abnormality" (2011-2014). Standardized data were collected. Statistical analysis was performed. RESULTS: Among 3308 cases, thymomas (27.8%), benign mediastinal cysts (20.0%), and lymphomas (16.1%) were most common. The distribution of lesions varied among mediastinal compartments; thymomas (38.3%), benign cysts (16.8%), and neurogenic tumors (53.9%) were the most common lesions in the prevascular, visceral, and paravertebral mediastinum, respectively (p < 0.001). Mediastinal compartment was associated with age; patients with paravertebral lesions were the youngest (p < 0.0001). Mediastinal lesions differed by continent or country, with benign cysts being the most common mediastinal lesions in the People's Republic of China, thymomas in Europe, and lymphomas in North America and Israel (p < 0.001). Benign cysts, thymic carcinomas, and metastases were more often seen in larger hospitals, whereas lymphomas and thymic hyperplasia occurred more often in smaller hospitals (p < 0.01). CONCLUSIONS: Our study confirmed that the spectrum and frequency of mediastinal lesions depend on mediastinal compartment and age. This information provides helpful demographic data and is important when considering the differential diagnosis of a mediastinal lesion.

Case presentation and recommendations from the April 2018 ITMIG tumor board: an international multidisciplinary team.

The International Thymic Malignancy Interest Group (ITMIG) has periodic tumor board meetings to discuss challenging cases. The case of a pediatric thymoma from the April 2018 meeting is discussed in this article. Radiology imaging and pathology slides are reviewed. Treatment and surveillance recommendations are discussed, as well as lessons learned from group discussion.