Immunotherapy and radiotherapy for older patients with locally advanced rectal cancer unfit for surgery or decline surgery: a practical proposal by the International Geriatric Radiotherapy Group.

The standard of care for locally advanced rectal cancer is total neoadjuvant therapy followed by surgical resection. Current evidence suggests that selected patients may be able to delay or avoid surgery without affecting survival rates if they achieve a complete clinical response (CCR). However, for older cancer patients who are too frail for surgery or decline the surgical procedure, local recurrence may lead to a deterioration of patient quality of life. Thus, for clinicians, a treatment algorithm which is well tolerated and may improve CCR in older and frail patients with rectal cancer may improve the potential for prolonged remission and potential cure. Recently, immunotherapy with check point inhibitors (CPI) is a promising treatment in selected patients with high expression of program death ligands receptor 1 (PD- L1). Radiotherapy may enhance PD-L1 expression in rectal cancer and may improve response rate to immunotherapy. We propose an algorithm combining immunotherapy and radiotherapy for older patients with locally advanced rectal cancer who are too frail for surgery or who decline surgery.

Low-Dose Apalutamide in Nonmetastatic Castration-Resistant Prostate Cancer: A Case Report.

The effect of low-dose apalutamide in nonmetastatic castration-resistant prostate cancer is unknown. We report the observation of therapy being administered at 25% of the recommended dose in an 80-year-old patient. Despite treatment discontinuation during COVID lockdowns, he survived three years without evidence of metastasis. This case gently invites us to reflect on the possibility of low-dose apalutamide in the elderly.

Lung-heart toxicity in a randomized clinical trial of hypofractionated image guided radiation therapy for breast cancer.

Background: TomoBreast hypothesized that hypofractionated 15 fractions/3 weeks image-guided radiation therapy (H-IGRT) can reduce lung-heart toxicity, as compared with normofractionated 25-33 fractions/5-7 weeks conventional radiation therapy (CRT). Methods: In a single center 123 women with stage I-II operated breast cancer were randomized to receive CRT (N=64) or H-IGRT (N=59). The primary endpoint used a composite four-items measure of the time to 10% alteration in any of patient-reported outcomes, physician clinical evaluation, echocardiography or lung function tests, analyzed by intention-to-treat. Results: At 12 years median follow-up, overall and disease-free survivals between randomized arms were comparable, while survival time free from alteration significantly improved with H-IGRT which showed a gain of restricted mean survival time of 1.46 years over CRT, P=0.041. Discussion: The finding establishes TomoBreast as a proof-of-concept that hypofractionated image-guided radiation-therapy can improve the sparing of lung-heart function in breast cancer adjuvant therapy without loss in disease-free survival. Hypofractionation is advantageous, conditional on using an advanced radiation technique. Multicenter validation may be warranted. Trial registration: https://clinicaltrials.gov/ct2/show/NCT00459628. Registered 12 April 2007.

Immunotherapy and Hypofractionated Radiotherapy in Older Patients with Locally Advanced Cutaneous Squamous-Cell Carcinoma of the Head and Neck: A Proposed Paradigm by the International Geriatric Radiotherapy Group.

Cutaneous skin carcinoma is a disease of older patients. The prevalence of cutaneous squamous-cell carcinoma (cSCC) increases with age. The head and neck region is a frequent place of occurrence due to exposure to ultraviolet light. Surgical resection with adjuvant radiotherapy is frequently advocated for locally advanced disease to decrease the risk of loco-regional recurrence. However, older cancer patients may not be candidates for surgery due to frailty and/or increased risk of complications. Radiotherapy is usually advocated for unresectable patients. Compared to basal-cell carcinoma, locally advanced cSCC tends to recur locally and/or can metastasize, especially in patients with high-risk features such as poorly differentiated histology and perineural invasion. Thus, a new algorithm needs to be developed for older patients with locally advanced head and neck cutaneous squamous-cell carcinoma to improve their survival and conserve their quality of life. Recently, immunotherapy with checkpoint inhibitors (CPIs) has attracted much attention due to the high prevalence of program death ligand 1 (PD-L1) in cSCC. A high response rate was observed following CPI administration with acceptable toxicity. Those with residual disease may be treated with hypofractionated radiotherapy to minimize the risk of recurrence, as radiotherapy may enhance the effect of immunotherapy. We propose a protocol combining CPIs and hypofractionated radiotherapy for older patients with locally advanced cutaneous head and neck cancer who are not candidates for surgery. Prospective studies should be performed to verify this hypothesis.

Impact of COVID-19 pandemic on older cancer patients: Proposed solution by the International Geriatric Radiotherapy Group.

Older cancer patients are disproportionally affected by the Coronavirus 19 (COVID-19) pandemic. A higher rate of death among the elderly and the potential for long-term disability have led to fear of contracting the virus in these patients. This fear can, paradoxically, cause delay in diagnosis and treatment that may lead to a poor outcome that could have been prevented. Thus, physicians should devise a policy that both supports the needs of older patients during cancer treatment, and serves to help them overcome their fear so they seek out to cancer diagnosis and treatment early. A combination of telemedicine and a holistic approach, involving prayers for older cancer patients with a high level of spirituality, may improve vaccination rates as well as quality of life during treatment. Collaboration between health care workers, social workers, faith-based leaders, and cancer survivors may be crucial to achieve this goal. Social media may be an important component, providing a means of sending the positive message to older cancer patients that chronological age is not an impediment to treatment.

Lung-Heart Outcomes and Mortality through the 2020 COVID-19 Pandemic in a Prospective Cohort of Breast Cancer Radiotherapy Patients.

We investigated lung-heart toxicity and mortality in 123 women with stage I-II breast cancer enrolled in 2007-2011 in a prospective trial of adjuvant radiotherapy (TomoBreast). We were concerned whether the COVID-19 pandemic affected the outcomes. All patients were analyzed as a single cohort. Lung-heart status was reverse-scored as freedom from adverse-events (fAE) on a 1-5 scale. Left ventricular ejection fraction (LVEF) and pulmonary function tests were untransformed. Statistical analyses applied least-square regression to calendar-year aggregated data. The significance of outliers was determined using the Dixon and the Grubbs corrected tests. At 12.0 years median follow-up, 103 patients remained alive; 10-years overall survival was 87.8%. In 2007-2019, 15 patients died, of whom 11 were cancer-related deaths. In 2020, five patients died, none of whom from cancer. fAE and lung-heart function declined gradually over a decade through 2019, but deteriorated markedly in 2020: fAE dipped significantly from 4.6-4.6 to 4.3-4.2; LVEF dipped to 58.4% versus the expected 60.3% (PDixon = 0.021, PGrubbs = 0.054); forced vital capacity dipped to 2.4 L vs. 2.6 L (PDixon = 0.043, PGrubbs = 0.181); carbon-monoxide diffusing capacity dipped to 12.6 mL/min/mmHg vs. 15.2 (PDixon = 0.008, PGrubbs = 0.006). In conclusion, excess non-cancer mortality was observed in 2020. Deaths in that year totaled one-third of the deaths in the previous decade, and revealed observable lung-heart deterioration.

Immunotherapy and Modern Radiotherapy Technique for Older Patients with Locally Advanced Head and Neck Cancer: A Proposed Paradigm by the International Geriatric Radiotherapy Group.

The standard of care for locally advanced head and neck cancer is concurrent chemoradiation or postoperative irradiation with or without chemotherapy. Surgery may not be an option for older patients (70 years old or above) due to multiple co-morbidities and frailty. Additionally, the standard chemotherapy of cisplatin may not be ideal for those patients due to oto- and nephrotoxicity. Though carboplatin is a reasonable alternative for cisplatin in patients with a pre-existing hearing deficit or renal dysfunction, its efficacy may be inferior to cisplatin for head and neck cancer. In addition, concurrent chemoradiation is frequently associated with grade 3-4 mucositis and hematologic toxicity leading to poor tolerance among older cancer patients. Thus, a new algorithm needs to be developed to provide optimal local control while minimizing toxicity for this vulnerable group of patients. Recently, immunotherapy with check point inhibitors (CPI) has attracted much attention due to the high prevalence of program death-ligand 1 (PD-L1) in head and neck cancer. In patients with recurrent or metastatic head and neck cancer refractory to cisplatin-based chemotherapy, CPI has proven to be superior to conventional chemotherapy for salvage. Those with a high PD-L1 expression defined as 50% or above or a high tumor proportion score (TPS) may have an excellent response to CPI. This selected group of patients may be candidates for CPI combined with modern radiotherapy techniques, such as intensity-modulated image-guided radiotherapy (IM-IGRT), volumetric arc therapy (VMAT) or proton therapy if available, which allow for the sparing of critical structures, such as the salivary glands, oral cavity, cochlea, larynx and pharyngeal muscles, to improve the patients' quality of life. In addition, normal organs that are frequently sensitive to immunotherapy, such as the thyroid and lungs, are spared with modern radiotherapy techniques. In fit or carefully selected frail patients, a hypofractionated schedule may be considered to reduce the need for daily transportation. We propose a protocol combining CPI and modern radiotherapy techniques for older patients with locally advanced head and neck cancer who are not eligible for cisplatin-based chemotherapy and have a high TPS. Prospective studies should be performed to verify this hypothesis.

Is immunotherapy at reduced dose and radiotherapy for older patients with locally advanced non-small lung cancer feasible?-a narrative review by the international geriatric radiotherapy group.

Background and Objective: The standard of care for locally advanced non-small cell lung cancer (NSCLC) is either surgery followed by adjuvant chemotherapy with or without radiotherapy or concurrent chemotherapy and radiotherapy. However, older patients (70 years old or above) with multiple co-morbidities may not be able to tolerate the combined treatment due to its toxicity. Since lung cancer prevalence increases significantly with age, a new algorithm needs to be investigated to allow curative treatment for those with locally advanced disease. Methods: A literature search of the literature was conducted through PubMed and Google Scholar using search terms such as locally advanced NSCLC, older cancer patients, immunotherapy with check point inhibitors (CPI), and image-guided radiotherapy (IGRT). Abstracts were screened, full articles fitting the article topic were reviewed, and duplicated and non-English articles were excluded. Key Content and Findings: Recently, CPI has been introduced and proven effective for selected patients with increased program death ligand 1 (PD-L1) expression (50% or above). A reduced dose for CPI (RDCPI) may be as effective as a full dose and may decrease treatment cost. New radiation technique such as IGRT may also minimize radiotherapy complication through normal lung and cardiac sparing. Conclusions: IGRT and RDCPI may be an innovative option for older patients with locally advanced NSCLC and high PD-L1 expression and needs to be investigated in future prospective studies.

Low-Dose Enzalutamide in Metastatic Prostate Cancer-Longevity Over Conventional Survival Analysis.

BACKGROUND: Enzalutamide is an important drug in the treatment of prostate cancer. Standard dosing often requires dose reduction because of side effects. There is no information on survival outcomes with lower doses. We investigated the impact of starting enzalutamide at ≤ 50% dose on metastatic prostate cancer outcomes including patients' longevity. PATIENTS AND METHODS: Records of metastatic prostate cancer patients treated with enzalutamide at one center were retrospectively reviewed. Low-dose enzalutamide (≤80 mg/day) was compared with standard-dose (160 mg/day). The primary objective was to compute the restricted mean survival time (RMST - time scale) and restricted mean attained age (RMAA - age scale) using the Irwin method. Secondary objectives included overall survival (OS), progression-free survival (PFS), and PSA progression per PCWG3 criteria (PSA PFS). We used the logrank test and the ∆ difference between RMSTs for comparison. RESULTS: Of 111 patients treated, 32 received a low-dose and 79 the standard-dose. Low-dose patients had less prior abiraterone or chemotherapy (28.1% vs. 65.8%, P < .001); more testosterone assessment (65.6% vs. 40.5%, P = .016); poorer ECOG performance status (48.3% score ≥2 vs. 26.6%; P = .040), more comorbidities (75.9% vs. 46.3%; P = .010)) including increased cardiovascular disease (51.7% vs. 21.4%, P = .004). Baseline PSA value and doubling time at start of enzalutamide and distribution of metastases were similar between the groups. OS and PFS did not differ between low-dose and standard-dose. Patients on low-dose had a better longevity with significantly longer RMAA, 89.1 years, versus standard-dose RMAA of 83.8 years (∆ = 5.3 years, P = .003, logrank P = .025). In a subgroup analysis by age at start of enzalutamide, <75 versus ≥75 years old, longevity was also better with low-dose in younger patients (∆ = 2.9 years, P = .034, and older, ∆ = 3.3 years, P = .011). CONCLUSION: The longevity advantage and reduced adverse events seen in patients with prostate cancer treated with low-dose enzalutamide warrants further investigation.

Is there utility for fluorine-18-fluorodeoxyglucose positron-emission tomography scan before surgery in breast cancer? A 15-year overall survival analysis.

BACKGROUND: The prognostic value of preoperative fluorine-18-fluorodeoxyglucose positron-emission tomography (18F-FDG PET) scan for determining overall survival (OS) in breast cancer (BC) patients is controversial. AIM: To evaluate the OS predictive value of preoperative PET positivity after 15 years. METHODS: We performed a retrospective search of the Universitair Ziekenhuis Brussel patient database for nonmetastatic patients who underwent preoperative PET between 2002-2008. PET positivity was determined by anatomical region of interest (AROI) findings for breast and axillary, sternal, and distant sites. The prognostic role of PET was examined as a qualitative binary factor (positive vs negative status) and as a continuous variable [maximum standard uptake value (SUVmax)] in multivariate survival analyses using Cox proportional hazards models. Among the 104 identified patients who received PET, 36 were further analyzed for the SUVmax in the AROI. RESULTS: Poor OS within the 15-year study period was predicted by PET-positive status for axillary (P = 0.033), sternal (P = 0.033), and combined PET-axillary/sternal (P = 0.008) nodes. Poor disease-free survival was associated with PET-positive axillary status (P = 0.040) and combined axillary/sternal status (P = 0.023). Cox models confirmed the long-term prognostic value of combined PET-axillary/sternal status [hazard ratio (HR): 3.08, 95% confidence interval: 1.42-6.69]. SUVmax of ipsilateral breast and axilla as continuous covariates were significant predictors of long-term OS with HRs of 1.25 (P = 0.048) and 1.54 (P = 0.029), corresponding to relative increase in the risk of death of 25% and 54% per SUVmax unit, respectively. In addition, the ratio of the ipsilateral axillary SUVmax over the contralateral axillary SUVmax was the most significant OS predictor (P = 0.027), with 1.94 HR, indicating a two-fold relative increase of mortality risk. CONCLUSION: Preoperative PET is valuable for prediction of long-term survival. Ipsilateral axillary SUVmax ratio over the uninvolved side represents a new prognostic finding that warrants further investigation.

Gini's mean difference and the long-term prognostic value of nodal quanta classes after pre-operative chemotherapy in advanced breast cancer.

Gini's mean difference (GMD, mean absolute difference between any two distinct quantities) of the restricted mean survival times (RMSTs, expectation of life at a given time limit) has been proposed as a new metric where higher GMD indicates better prognostic value. GMD is applied to the RMSTs at 25 years time-horizon to evaluate the long-term overall survival of women with breast cancer who received neoadjuvant chemotherapy, comparing a classification based on the number (pN) versus a classification based on the ratio (LNRc) of positive nodes found at axillary surgery. A total of 233 patients treated in 1980-2009 with documented number of positive nodes (npos) and number of nodes examined (ntot) were identified. The numbers were categorized into pN0, npos = 0; pN1, npos = [1,3]; pN2, npos = [4,9]; pN3, npos ≥ 10. The ratios npnx = npos/ntot were categorized into Lnr0, npnx = 0; Lnr1, npnx = (0,0.20]; Lnr2, npnx = (0.20,0.65]; Lnr3, npnx > 0.65. The GMD for pN-classification was 5.5 (standard error: ± 0.9) years, not much improved over a simple node-negative vs. node-positive that showed a GMD of 5.0 (± 1.4) years. The GMD for LNRc-classification was larger, 6.7 (± 0.8) years. Among other conventional metrics, Cox-model LNRc's c-index was 0.668 vs. pN's c = 0.641, indicating commensurate superiority of LNRc-classification. The usability of GMD-RMSTs warrants further investigation.

Prone versus supine free-breathing for right-sided whole breast radiotherapy.

Prone setup has been advocated to improve organ sparing in whole breast radiotherapy without impairing breast coverage. We evaluate the dosimetric advantage of prone setup for the right breast and look for predictors of the gain. Right breast cancer patients treated in 2010-2013 who had a dual supine and prone planning were retrospectively identified. A penalty score was computed from the mean absolute dose deviation to heart, lungs, breasts, and tumor bed for each patient's supine and prone plan. Dosimetric advantage of prone was assessed by the reduction of penalty score from supine to prone. The effect of patients' characteristics on the reduction of penalty was analyzed using robust linear regression. A total of 146 patients with right breast dual plans were identified. Prone compared to supine reduced the penalty score in 119 patients (81.5%). Lung doses were reduced by 70.8%, from 4.8 Gy supine to 1.4 Gy prone. Among patient's characteristics, the only significant predictors were the breast volumes, but no cutoff could identify when prone would be less advantageous than supine. Prone was associated with a dosimetric advantage in most patients. It sets a benchmark of achievable lung dose reduction.Trial registration: ClinicalTrials.gov NCT02237469, HUGProne, September 11, 2014, retrospectively registered.

Stereotactic Body Radiotherapy and Immunotherapy for Older Patients with Oligometastases: A Proposed Paradigm by the International Geriatric Radiotherapy Group.

The standard of care for metastatic disease is systemic therapy. A unique subset of patients with limited metastatic disease defined as distant involvement of five anatomic sites or less (oligometastases) have a better chance of remission or improved survival and may benefit from local treatments such as surgery or stereotactic body radiotherapy (SBRT). However, to prevent further spread of disease, systemic treatment such as chemotherapy, targeted therapy, and hormonal therapy may be required. Older patients (70 years old or above) or physiologically frail younger patients with multiple co-morbidities may not be able to tolerate the conventional chemotherapy due to its toxicity. In addition, those with a good performance status may not receive optimal chemotherapy due to concern about toxicity. Recently, immunotherapy with checkpoint inhibitors (CPI) has become a promising approach only in the management of program death ligand 1 (PD-L1)-positive tumors. Thus, a treatment method that elicits induction of PD-L1 production by tumor cells may allow all patients with oligometastases to benefit from immunotherapy. In vitro studies have demonstrated that high dose of radiotherapy may induce formation of PD-L1 in various tumors as a defense mechanism against inflammatory T cells. Clinical studies also corroborated those observations. Thus, SBRT, with its high precision to minimize damage to normal organs, may be a potential treatment of choice for older patients with oligometastases due to its synergy with immunotherapy. We propose a protocol combining SBRT to achieve a minimum radiobiologic equivalent dose around 59.5 Gy to all tumor sites if feasible, followed four to six weeks later by CPI for those cancer patients with oligometastases. All patients will be screened with frailty screening questionnaires to identify individuals at high risk for toxicity. The patients will be managed with an interdisciplinary team which includes oncologists, geriatricians, nurses, nutritionists, patient navigators, and social workers to manage all aspects of geriatric patient care. The use of telemedicine by the team may facilitate patient monitoring during treatment and follow-up. Preliminary data on toxicity, local control, survival, and progression-free survival may be obtained and serve as a template for future prospective studies.

Cardiopulmonary-related patient-reported outcomes in a randomized clinical trial of radiation therapy for breast cancer.

BACKGROUND: Long-term prospective patient-reported outcomes (PRO) after breast cancer adjuvant radiotherapy is scarce. TomoBreast compared conventional radiotherapy (CR) with tomotherapy (TT), on the hypothesis that TT might reduce lung-heart toxicity. METHODS: Among 123 women consenting to participate, 64 were randomized to CR, 59 to TT. CR delivered 50 Gy in 25 fractions/5 weeks to breast/chest wall and regional nodes if node-positive, with a sequential boost (16 Gy/8 fractions/1.6 weeks) after lumpectomy. TT delivered 42 Gy/15 fractions/3 weeks to breast/chest wall and regional nodes if node-positive, 51 Gy simultaneous-integrated-boost in patients with lumpectomy. PRO were assessed using the European Organization for Research and Treatment of Cancer questionnaire QLQ-C30. PRO scores were converted into a symptom-free scale, 100 indicating a fully symptom-free score, 0 indicating total loss of freedom from symptom. Changes of PRO over time were analyzed using the linear mixed-effect model. Survival analysis computed time to > 10% PRO-deterioration. A post-hoc cardiorespiratory outcome was defined as deterioration in any of dyspnea, fatigue, physical functioning, or pain. RESULTS: At 10.4 years median follow-up, patients returned on average 9 questionnaires/patient, providing a total of 1139 PRO records. Item completeness was 96.6%. Missingness did not differ between the randomization arms. The PRO at baseline were below the nominal 100% symptom-free score, notably the mean fatigue-free score was 64.8% vs. 69.6%, pain-free was 75.4% vs. 75.3%, and dyspnea-free was 84.8% vs. 88.5%, in the TT vs. CR arm, respectively, although the differences were not significant. By mixed-effect modeling on early ≤2 years assessment, all three scores deteriorated, significantly for fatigue, P ≤ 0.01, without effect of randomization arm. By modeling on late assessment beyond 2 years, TT versus CR was not significantly associated with changes of fatigue-free or pain-free scores but was associated with a significant 8.9% improvement of freedom from dyspnea, P = 0.035. By survival analysis of the time to PRO deterioration, TT improved 10-year survival free of cardiorespiratory deterioration from 66.9% with CR to 84.5% with TT, P = 0.029. CONCLUSION: Modern radiation therapy can significantly improve long-term PRO. TRIAL REGISTRATION: Trial registration number ClinicalTrials.gov NCT00459628 , April 12, 2007 prospectively.

Lymph Node Ratio after Neoadjuvant Chemotherapy for Stage II/III Breast Cancer: Prognostic Value Measured with Gini's Mean Difference of Restricted Mean Survival Times.

Restricted mean survival time (RMST), recommended for reporting survival, lacks a tool to evaluate multilevel factors. The potential of the Gini's mean difference of RMSTs (Δ) is explored in a comparison of a lymph node ratio-based classification (LNRc) versus a number-based classification (ypN) applied to stage II/III breast cancer patients who received neoadjuvant chemotherapy and underwent axillary dissection. Number of positive nodes (npos) classified patients into ypN0, npos = 0, ypN1, npos = [1,3], ypN2, npos = [4,9], and ypN3, npos ⩾ 10. Ratio npos/(number of nodes examined) of 0, (0,0.20], (0.20,0.65], and >0.65, classified patients into Lnr0 to Lnr3, respectively. Unadjusted and Cox-adjusted RMSTs were computed for the ypN and LNRc's. At a follow-up time horizon of 72 months for 114 node-negative and 254 node-positive patients, unadjusted ypN0-ypN3 RMSTs were 62.4-41.4 months, Δ = 11.9 months (95%CI: 7.4-16.9), and Lnr0-Lnr3 62.4 to 36.3 months, Δ = 14.0 months (95%CI: 10.1-18.1). Cox models' ypN1-ypN3 hazard ratios were 1.81-3.30, and Lnr1-Lnr3 1.52-4.39. Δ from Cox-fitted survival were ypN 8.1 months (95%CI: 5.9-10.5), LNRc 10.5 months (95%CI: 8.4-12.8). In conclusion, Gini's mean difference is applicable to well established data in keeping with the literature on LNRc. It provides an alternative view on the improvement gained with a lymph node ratio-classification over using a number-classification.

Breast cancer preoperative 18FDG-PET, overall survival prognostic separation compared with the lymph node ratio.

PURPOSE: To evaluate the overall survival prognostic value of preoperative 18F-fluorodeoxyglucose positron emission tomography (PET) in breast cancer, as compared with the lymph node ratio (LNR). METHODS: Data were abstracted at a median follow-up 14.7 years from a retrospective cohort of 104 patients who underwent PET imaging before curative surgery. PET-Axillary|Sternal was classified as PET-positive if hypermetabolism was visualized in ipsilateral nodal axillary and/or sternal region, else as PET-negative. The differences of 15 years restricted mean survival time ∆RMST according to PET and LNR were computed from Kaplan-Meier overall survival. The effect of PET and other patients' characteristics was analyzed through rankit normalization, which provides with Cox regression the Royston-Sauerbrei D measure of separation to compare the characteristics (0 indicating no prognostic value). Multivariate analysis of the normalized characteristics used stepwise selection with the Akaike information criterion. RESULTS: In Kaplan-Meier analysis, LNR > 0.20 versus ≤ 0.20 showed ∆RMST = 3.4 years, P = 0.003. PET-Axillary|Sternal positivity versus PET-negative showed a ∆RMST = 2.6 years, P = 0.008. In Cox univariate analyses, LNR appeared as topmost prognostic separator, D = 1.50, P < 0.001. PET ranked below but was also highly significant, D = 1.02, P = 0.009. In multivariate analyses, LNR and PET-Axillary|Sternal were colinear and mutually exclusive. PET-Axillary|Sternal improved as prognosticator in a model excluding lymph nodes, yielding a normalized hazard ratio of 2.44, P = 0.062. CONCLUSION: Pathological lymph node assessment remains the gold standard of prognosis. However, PET appears as a valuable surrogate in univariate analysis at 15-year follow-up. There was a trend towards significance in multivariate analysis that warrants further investigation.

Is prone free breathing better than supine deep inspiration breath-hold for left whole-breast radiotherapy? A dosimetric analysis.

PURPOSE: The advantage of prone setup compared with supine for left-breast radiotherapy is controversial. We evaluate the dosimetric gain of prone setup and aim to identify predictors of the gain. METHODS: Left-sided breast cancer patients who had dual computed tomography (CT) planning in prone free breathing (FB) and supine deep inspiration breath-hold (DiBH) were retrospectively identified. Radiation doses to heart, lungs, breasts, and tumor bed were evaluated using the recently developed mean absolute dose deviation (MADD). MADD measures how widely the dose delivered to a structure deviates from a reference dose specified for the structure. A penalty score was computed for every treatment plan as a weighted sum of the MADDs normalized to the breast prescribed dose. Changes in penalty scores when switching from supine to prone were assessed by paired t-tests and by the number of patients with a reduction of the penalty score (i.e., gain). Robust linear regression and fractional polynomials were used to correlate patients' characteristics and their respective penalty scores. RESULTS: Among 116 patients identified with dual CT planning, the prone setup, compared with supine, was associated with a dosimetric gain in 72 (62.1%, 95% CI: 52.6-70.9%). The most significant predictors of a gain with the prone setup were the breast depth prone/supine ratio (>1.6), breast depth difference (>31 mm), prone breast depth (>77 mm), and breast volume (>282 mL). CONCLUSION: Prone compared with supine DiBH was associated with a dosimetric gain in 62.1% of our left-sided breast cancer patients. High pendulousness and moderately large breast predicted for the gain.

Two-Level Factorial Pre-TomoBreast Pilot Study of Tomotherapy and Conventional Radiotherapy in Breast Cancer: Post Hoc Utility of a Mean Absolute Dose Deviation Penalty Score.

BACKGROUND: A 2-level factorial pilot study was conducted in 2007 just before starting a randomized clinical trial comparing tomotherapy and conventional radiotherapy (CR) to reduce cardiac and pulmonary adverse effects in breast cancer, considering tumor laterality (left/right), target volume (with/without nodal irradiation), surgery (tumorectomy/mastectomy), and patient position (prone/supine). The study was revisited using a penalty score based on the recently developed mean absolute dose deviation (MADD). METHODS: Eight patients with a unique combination of laterality, nodal coverage, and surgery underwent dual tomotherapy and CR treatment planning in both prone and supine positions, providing 32 distinct combinations. The penalty score was applied using the weighted sum of the MADDs. The Lenth method for unreplicated 2-level factorial design was used in the analysis. RESULTS: The Lenth analysis identified nodal irradiation as the active main effect penalizing the dosimetry by 1.14 Gy (P = 0.001). Other significant effects were left laterality (0.94 Gy), mastectomy (0.61 Gy), and interactions between left mastectomy (0.89 Gy) and prone mastectomy (0.71 Gy), with P-values between 0.005 and 0.05. Tomotherapy provided a small reduction in penalty (reduction of 0.54 Gy) through interaction with nodal irradiation (P = 0.080). Some effects approached significance with P-values > 0.05 and ≤ 0.10 for interactions of prone × mastectomy × left (0.60 Gy), nodal irradiation × mastectomy (0.59 Gy), and prone × left (0.55 Gy) and the main effect prone (0.52 Gy). CONCLUSIONS: The historical dosimetric analysis previously revealed the feasibility of tomotherapy, but a conclusion could not be made. The MADD-based score is promising, and a new analysis highlights the impact of factors and hierarchy of priorities that need to be addressed if major gains are to be attained.

Low-Dose Enzalutamide in Late-Elderly Patients (≥ 75 Years Old) Presenting With Metastatic Castration-Resistant Prostate Cancer.

BACKGROUND: Enzalutamide, a major antiandrogen indicated for metastatic castration-resistant prostate cancer, has worrisome toxicities in aging patients. Dose reduction might limit toxicity, but potential loss of efficacy is a concern. We compare up-front low-dose versus standard-dose enzalutamide. PATIENTS AND METHODS: Records of prostate cancer patients receiving enzalutamide were retrospectively retrieved. Selection criteria were: age ≥ 75, metastatic disease, surgical or medical castration, and rising prostate-specific antigen (PSA). Data were excluded of those missing follow-up PSA values. Low-dose enzalutamide (≤ 80 mg per day) was compared to standard dose (160 mg per day). Progression-free survival analyzed the time from start of enzalutamide to event, defined as ≥ 25% and ≥ 2 ng/mL PSA increase above nadir, or death from any cause. RESULTS: Fifty-nine patients were identified, of whom 16 received low-dose and 43 standard-dose therapy. Patients in the low-dose group were significantly old, with a median (range) age of 84.6 (74.9-93.8) years; median (range) PSA at start of enzalutamide was 59.2 (11.0-1058.3) ng/mL; 11 had bone metastases only, 2 metastatic lymph nodes only, and 3 bone and lymph node localizations. Pain score was > 3/10 in 4 patients (27%), Eastern Cooperative Oncology Group performance status was ≥ 2 in 9 (56%); 3 patients had received prior abiraterone and 3 bicalutamide. None received chemotherapy. PSA decrease of ≥ 50% at 12 weeks was observed in 67% patients (10/15), versus 45.0% with standard dose. Median (range) PSA at last follow-up was 1.6 (0-599.3) ng/mL. Median progression-free survival was 11.2 months, versus 11.9 months for patients receiving the standard dose (P = .612). CONCLUSION: Low-dose enzalutamide in very old, symptomatic, poor-performance patients with metastatic disease was associated with high response rate and survival comparable to standard dose.