Large-scale unit commitment under uncertainty: an updated literature survey

The Unit Commitment problem in energy management aims at finding the optimal production schedule of a set of generation units, while meeting various system-wide constraints. It has always been a large-scale, non-convex, difficult problem, especially in view of the fact that, due to operational requirements, it has to be solved in an unreasonably small time for its size. Recently, growing renewable energy shares have strongly increased the level of uncertainty in the system, making the (ideal) Unit Commitment model a large-scale, non-convex and uncertain (stochastic, robust, chance-constrained) program. We provide a survey of the literature on methods for the Uncertain Unit Commitment problem, in all its variants. We start with a review of the main contributions on solution methods for the deterministic versions of the problem, focussing on those based on mathematical programming techniques that are more relevant for the uncertain versions of the problem. We then present and categorize the approaches to the latter, while providing entry points to the relevant literature on optimization under uncertainty. This is an updated version of the paper "Large-scale Unit Commitment under uncertainty: a literature survey" that appeared in 4OR 13(2), 115--171 (2015); this version has over 170 more citations, most of which appeared in the last three years, proving how fast the literature on uncertain Unit Commitment evolves, and therefore the interest in this subject

Impact of inflammatory markers on survival in patients with limited disease small-cell lung cancer undergoing chemoradiotherapy

Denise Bernhardt,1–3,* Sophie Aufderstrasse,1,2,* Laila König,1–3 Sebastian Adeberg,1–4 Farastuk Bozorgmehr,5,6 Petros Christopoulos,5,6 Rami A El Shafie,1,2 Juliane Hörner-Rieber,1–3 Jutta Kappes,6,7 Michael Thomas,5,6 Felix Herth,6,7 Martin Steins,5 Jürgen Debus,1–4 Stefan Rieken1–3 1Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany; 2Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg, Germany; 3Heidelberg Ion-Beam Therapy Center (HIT), Heidelberg, Germany; 4Clinical Cooperation Unit Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany; 5Department of Thoracic Oncology, Thoraxklinik, Heidelberg University, Translational Lung Research Centre Heidelberg (TLRC-H), Heidelberg, Germany; 6German Centre for Lung Research (DZL), Heidelberg, Germany; 7Department of Pneumology, Thoraxklinik, Heidelberg University, Heidelberg, Germany *These authors contributed equally to this work Background: Systemic inflammation appears to play a role in the progression of numerous solid tumors by promoting tumor proliferation. Our current study aimed to evaluate the role of inflammatory markers in limited disease (LD) small-cell lung cancer (SCLC) patients undergoing thoracic chemoradiotherapy (TCR). Patients and methods: We retrospectively analyzed a total number of 350 SCLC patients diagnosed with LD SCLC who received TCR between 1999 and 2017 and had available blood tests within 2 weeks prior to the start of TCR. Serum C-reactive protein (CRP), neutrophil-to-lymphocyte ratio (NLR), lactate dehydrogenase (LDH), hemoglobin (Hb) levels, and platelet count (Pc) were evaluated as potential inflammatory markers. Kaplan–Meier survival analysis was performed for overall survival (OS). For comparison of survival curves, the log-rank (­Mantel–Cox) test was used. Univariate and multivariate Cox proportional HRs were used to assess the influence of cofactors on OS. Results: Univariate analysis for OS revealed a statistically significant effect for LDH >400 U/L (HR 2.05 U/L; 95% CI 1.29–3.26 U/L; P=0.002), prophylactic cranial irradiation (PCI; HR 0.58; 95% CI 0.40–0.85; P=0.005), CRP >50 mg/L (HR 1.49 mg/L; 95% CI 1.05–2.10 mg/L; P=0.026), and Karnofsky performance scale (KPS) <70% (HR 1.35%; 95% CI 1.02–1.80%; P=0.035). NLR, age (>70 years), Hb levels, and Pc did not influence survival. In multivariate analysis, OS was significantly affected by PCI (HR 0.64; 95% CI 0.43–0.94; P=0.026), LDH >400 U/L (HR 1.91 U/L; 95% CI 1.21–3.05 U/L; P=0.006), and CRP >50 mg/L (HR 1.43 mg/L; 95% CI 1.01–2.04 mg/L; P=0.045). KPS (≤70%) did not influence survival in multivariate analysis. Conclusion: Elevated CRP and LDH seem to be the independent prognostic factors for OS in LD SCLC patients undergoing TCR. However, elevated NLR was not found to be an independent prognostic factor for OS if taken prior to TCR. LDH and CRP are easily available blood tests and do not require additional resources for routine use and could be useful for clinical decision making. Keywords: small-cell lung cancer, limited disease, comorbidity, NLR, LDH, CR

Outcome and prognostic factors following palliative craniospinal irradiation for leptomeningeal carcinomatosis

Rami A El Shafie,1,2 Karina Böhm,1,2 Dorothea Weber,3 Kristin Lang,1,2 Fabian Schlaich,1,2 Sebastian Adeberg,1,2 Angela Paul,1,2,4 Matthias F Haefner,1,2 Sonja Katayama,1,2 Florian Sterzing,1,2,5 Juliane Hörner-Rieber,1,2 Sarah Löw,6 Klaus Herfarth,1,2,4 Jürgen Debus,1,2,4,7 Stefan Rieken,1,2,4 Denise Bernhardt1,2 1Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg 69120, Germany; 2National Center for Radiation Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg 69120, Germany; 3Institute of Medical Biometry and Informatics (IMBI), Heidelberg University Hospital, Heidelberg 69120, Germany; 4Heavy Ion Therapy Center (HIT), Heidelberg University Hospital, Heidelberg 69120, Germany; 5Department of Radiation Oncology, Klinikum Kempten, Kempten 87439, Germany; 6Department of Neurology, University Hospital of Heidelberg, Heidelberg 69120, Germany; 7German Cancer Research Center (DKFZ), Heidelberg 69120, Germany Background: Leptomeningeal carcinomatosis (LC) is a severe complication of metastatic tumor spread to the central nervous system. Prognosis is dismal with a median overall survival (OS) of ~10–15 weeks. Treatment options include radiotherapy (RT) to involved sites, systemic chemo- or targeted therapy, intrathecal chemotherapy and best supportive care with dexamethasone. Craniospinal irradiation (CSI) is a more aggressive radiotherapeutic approach, for which very limited data exists. Here, we report on our 10-year experience with palliative CSI of selected patients with LC. Patients and methods: Twenty-five patients received CSI for the treatment of LC at our institution between 2008 and 2018. Patients were selected individually for CSI based on clinical performance, presenting symptoms and estimated benefit. Median patient age was 53 years (IQR: 45–59), and breast cancer was the most common primary. Additional brain metastases were found in 18 patients (72.0%). RT was delivered at a TomoTherapy machine, using helical intensity-modulated radiotherapy (IMRT). The most commonly prescribed dose was 36 Gy in 20 fractions, corresponding to a median biologically equivalent dose of 40.8 Gy (IQR: 39.0– 2.5). Clinical performance and neurologic function were assessed before and in response to therapy, and deficits were retrospectively quantified on the 5-point neurologic function scale (NFS). A Cox proportional hazards model with univariate and multivariate analyses was fitted for survival.Results: Twenty-one patients died and four were alive at the time of analysis. Median OS from LC diagnosis was 19.3 weeks (IQR: 9.3–34.0, 95% CI: 11.0–32.0). In univariate analysis, a Karnofsky performance scale index (KPI) ≥70% (P=0.001), age ≤55 years at LC diagnosis (P=0.022), cerebrospinal fluid (CSF) protein <100 mg/dL (P=0.018) and no more than mild or moderate neurologic deficits (NFS ≤2; P=0.007) were predictive of longer OS. So were the neurologic response to treatment (P=0.018) and the application of systemic therapy after RT completion (P=0.029). The presence of CSF flow obstruction was predictive of shorter OS (P=0.026). In multivariate analysis, age at LC diagnosis (P=0.018), KPI (P<0.001) and neurologic response (P=0.037) remained as independent prognostic factors for longer OS. Treatment-associated toxicity was manageable andmostly grades I and II according to the Common Terminology Criteria for Adverse Events v4.0. Eight patients (32%) developed grade III myelosuppression. Neurologic symptom stabilization could be achieved in 40.0% and a sizeable improvement in 28.0% of all patients.Conclusion: CSI for the treatment of LC is feasible and may have therapeutic value in carefully selected patients, alleviating symptoms or delaying neurologic deterioration. OS after CSI was comparable to the rates described in current literature for patients with LC. The use of modern irradiation techniques such as helical IMRT is warranted to limit toxicity. Patient selection should take into account prognostic factors such as age, clinical performance, neurologic function and the availability of systemic treatment options. Keywords: leptomeningeal metastases, radiotherapy, TomoTherapy, carcinomatous meningitis, neuroaxis, neurologic functio