Adoption of Three-Dimensional Printing Technology in Public Housing in Singapore: Drivers, Challenges, and Strategies

Although emphasis has been placed on three-dimensional (3D) printing technology that can alleviate increasing demand and low-productivity issues in public housing developments, limited research has been conducted to examine perceptions surrounding this technology in the context of public housing projects in the built environment industry. Hence, this study aims to investigate the perceptions of practitioners working in the industry concerning the drivers, challenges, and strategies for 3D printing technology, together with the status quo of its implementation. To achieve these goals, nine drivers, eight challenges, and seven strategies were identified through a comprehensive literature review, followed by a structured questionnaire survey administered to industry practitioners. Based on the survey analyses, the top three drivers, challenges, and strategies were identified, and the differences in perceptions according to respondents and their organizational characteristics were explored. Moreover, postinterviews were carried out with several industry professionals to further substantiate the analyses results. The results serve as a starting point for the industry to reap the benefits from additive manufacturing technology throughout the project life cycle. This study contributes to the body of knowledge relating to the adoption of 3D printing technology in the industry, improving productivity in public housing projects and moving toward more sustainable and cleaner delivery processes in the built environment industry.N

Sarcopenia is negatively associated with long‐term outcomes in locally advanced rectal cancer

Abstract Background The association of sarcopenia and visceral obesity to treatment outcome is not clear for locally advanced rectal cancer. This study evaluates the influence of skeletal muscle and visceral fat on short‐term and long‐term outcomes in locally advanced rectal cancer patients treated with neoadjuvant chemoradiation therapy followed by curative resection. Methods A total of 188 patients with locally advanced cancer were included between January 2009 and December 2013. Neoadjuvant chemoradiotherapy was followed by curative resection. Sarcopenia and visceral obesity were identified in initial staging CT by measuring the muscle and visceral fat area at the third lumbar vertebra level. Results Among the 188 included patients, 74 (39.4%) patients were sarcopenic and 97 (51.6%) patients were viscerally obese. Sarcopenia and high levels of preoperative carcinoembryonic antigen were significant prognostic factors for overall survival (P = 0.013, 0.014, respectively) in the Cox regression multivariate analysis. Visceral obesity was not associated with overall survival; however, it did tend to shorten disease‐free survival (P = 0.079). Conclusions Sarcopenia is negatively associated with overall survival in locally advanced rectal cancer patients who underwent neoadjuvant chemoradiation therapy and curative resection. Visceral obesity tended to shorten disease‐free survival. Future studies should be directed to optimize patient conditions according to body composition status

Additional file 1: Fig. S1. of The prognostic significance of KRAS and BRAF mutation status in Korean colorectal cancer patients

Kaplan-Meier curves for DFS and OS between KRAS mutation at codon 12 and 13. A. DFS between KRAS mutation at codon 12 and 13 and B. OS between KRAS mutation at codon 12 and 13. (PPTX 266 kb

Lateral Nodal Features on Restaging Magnetic Resonance Imaging Associated With Lateral Local Recurrence in Low Rectal Cancer After Neoadjuvant Chemoradiotherapy or Radiotherapy

Key PointsQuestionWhat is the role of restaging magnetic resonance imaging (MRI) after chemoradiotherapy or radiotherapy, and which specific patients might benefit from a lateral lymph node dissection (LLND)? FindingsIn this multicenter pooled cohort study including 741 patients with low rectal cancer after chemoradiotherapy or radiotherapy, shrinkage of lateral nodes from a short-axis node size of 7 mm or greater on primary MRI to a short-axis node size of 4 mm or less on restaging MRI abolished the risk of lateral local recurrence (LLR). However, in persistently enlarged nodes (greater than 4 mm) in the internal iliac compartment on restaging MRI, the risk of LLR was high, and an LLND lowered this risk significantly. MeaningPersistently enlarged nodes in the internal iliac compartment indicate a high risk of LLR, and an LLND should be seriously considered in these patients. This cohort study investigates the factors on primary and restaging magnetic resonance imaging that are associated with lateral local recurrence in low rectal cancer after chemoradiotherapy or radiotherapy and to formulate specific guidelines on which patients might benefit from a lateral lymph node dissection. ImportancePreviously, it was shown in patients with low rectal cancer that a short-axis (SA) lateral node size of 7 mm or greater on primary magnetic resonance imaging (MRI) resulted in a high lateral local recurrence (LLR) rate after chemoradiotherapy or radiotherapy ([C]RT) with total mesorectal excision (TME) and that this risk was lowered by a lateral lymph node dissection (LLND). The role of restaging MRI after (C)RT with regard to LLR risk and which specific patients might benefit from an LLND is not fully understood. ObjectiveTo determine the factors on primary and restaging MRI that are associated with LLR in low rectal cancer after (C)RT and to formulate specific guidelines on which patients might benefit from an LLND. Design, Setting, and ParticipantsIn this retrospective, multicenter, pooled cohort study, patients who underwent surgery for cT3 or cT4 low rectal cancer with a curative intent from 12 centers in 7 countries from January 2009 to December 2013 were included. All patients' MRIs were rereviewed according to a standardized protocol, with specific attention to lateral nodal features. The original cohort included 1216 patients. For this study, patients who underwent (C)RT and had a restaging MRI were selected, leaving 741 for analyses across 10 institutions, including 651 who underwent (C)RT with TME and 90 who underwent (C)RT with TME and LLND. Main Outcomes and MeasuresThe main purpose was to identify the factors on primary and restaging MRI associated with LLR after (C)RT with TME. Whether high-risk patients might benefit in terms of LLR reduction from an LLND was also studied. ResultsOf the 741 included patients, 480 (64.8%) were male, and the mean (SD) age was 60.4 (12.0) years. An SA lateral node size of 7 mm or greater on primary MRI resulted in a 5-year LLR rate of 17.9% after (C)RT with TME. At 3 years, there were no LLRs in 28 patients (29.2%) with lateral nodes that were 4 mm or less on restaging MRI. Nodes that were 7 mm or greater on primary MRI and greater than 4 mm on restaging MRI in the internal iliac compartment resulted in a 5-year LLR rate of 52.3%, significantly higher compared with nodes in the obturator compartment of that size (9.5%; hazard ratio, 5.8; 95% CI, 1.6-21.3; P=.003). Compared with (C)RT with TME alone, treatment with (C)RT with TME and LLND in these unresponsive internal nodes resulted in a significantly lower LLR rate of 8.7% (hazard ratio, 6.2; 95% CI, 1.4-28.5; P=.007). Conclusions and RelevanceRestaging MRI is important in clinical decision making in lateral nodal disease. In patients with shrinkage of lateral nodes from an SA node size of 7 mm or greater on primary MRI to an SA node size of 4 mm or less on restaging MRI, which occurs in about 30% of cases, LLND can be avoided. However, persistently enlarged nodes in the internal iliac compartment indicate an extremely high risk of LLR, and an LLND lowered LLR in these cases