Rectal cancer, which accounts for approximately 40% of colorectal cancers, remains a major clinical concern. Recent advances in diagnostic imaging, surgical techniques, radiotherapy, and systemic treatment have steadily improved rectal cancer outcomes. Considering this, the Korean Rectal Cancer Multidisciplinary (KRCM) Committee has aimed to provide clinicians and policymakers with up-to-date, evidence-based clinical practice guidelines to support optimal decision-making, reflecting current evidence, the Korean healthcare context, and patient values and preferences. The Clinical Practice Guidelines for Rectal Cancer version 2.0 were developed through multidisciplinary collaboration with related academic societies, building upon and updating the KRCM Clinical Practice Guidelines version 1.0 (titled “Multidisciplinary guidelines for the management of rectal cancer”). These consensus guidelines of the KRCM were established based on a comprehensive literature review, evidence synthesis, with recommendation development guided by the GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology, and consideration of applicability in real-world clinical practice under the national health insurance system. Each recommendation has been presented with its strength and level of evidence.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

The restoration process for patients with collapsed occlusion or those requiring extensive rehabilitation often involves various trials and errors. Accurately transferring the patient’s oral information to the articulator is key to producing esthetically pleasing and stable prostheses. This necessitates precise master model fabrication and accurate jaw relation records. For patients undergoing extensive implant-supported fixed prostheses, several techniques for recording the jaw relationship are available, including the use of record bases with wax rims, bite blocks with temporary abutments and pattern resin, or provisional prostheses.Among these, using provisional prostheses directly for mounting on the master model can help minimize errors during the jaw relation recording phase. The patient in this case was a 55-year-old female patient, who presented for implant-supported fixed prosthetic rehabilitation. She exhibited multiple tooth loss due to periodontal disease, necessitating comprehensive mouth rehabilitation involving extractions and implant placements. After evaluating esthetics and occlusion with provisional prostheses, the same provisional prostheses were used for mounting on the master model, which enabled the fabrication of customized implant abutments and zirconia prostheses. The final result was a successful restoration, both esthetically and functionally.

The restoration process for patients with collapsed occlusion or those requiring extensive rehabilitation often involves various trials and errors. Accurately transferring the patient’s oral information to the articulator is key to producing esthetically pleasing and stable prostheses. This necessitates precise master model fabrication and accurate jaw relation records. For patients undergoing extensive implant-supported fixed prostheses, several techniques for recording the jaw relationship are available, including the use of record bases with wax rims, bite blocks with temporary abutments and pattern resin, or provisional prostheses.Among these, using provisional prostheses directly for mounting on the master model can help minimize errors during the jaw relation recording phase. The patient in this case was a 55-year-old female patient, who presented for implant-supported fixed prosthetic rehabilitation. She exhibited multiple tooth loss due to periodontal disease, necessitating comprehensive mouth rehabilitation involving extractions and implant placements. After evaluating esthetics and occlusion with provisional prostheses, the same provisional prostheses were used for mounting on the master model, which enabled the fabrication of customized implant abutments and zirconia prostheses. The final result was a successful restoration, both esthetically and functionally.

The restoration process for patients with collapsed occlusion or those requiring extensive rehabilitation often involves various trials and errors. Accurately transferring the patient’s oral information to the articulator is key to producing esthetically pleasing and stable prostheses. This necessitates precise master model fabrication and accurate jaw relation records. For patients undergoing extensive implant-supported fixed prostheses, several techniques for recording the jaw relationship are available, including the use of record bases with wax rims, bite blocks with temporary abutments and pattern resin, or provisional prostheses.Among these, using provisional prostheses directly for mounting on the master model can help minimize errors during the jaw relation recording phase. The patient in this case was a 55-year-old female patient, who presented for implant-supported fixed prosthetic rehabilitation. She exhibited multiple tooth loss due to periodontal disease, necessitating comprehensive mouth rehabilitation involving extractions and implant placements. After evaluating esthetics and occlusion with provisional prostheses, the same provisional prostheses were used for mounting on the master model, which enabled the fabrication of customized implant abutments and zirconia prostheses. The final result was a successful restoration, both esthetically and functionally.

The restoration process for patients with collapsed occlusion or those requiring extensive rehabilitation often involves various trials and errors. Accurately transferring the patient’s oral information to the articulator is key to producing esthetically pleasing and stable prostheses. This necessitates precise master model fabrication and accurate jaw relation records. For patients undergoing extensive implant-supported fixed prostheses, several techniques for recording the jaw relationship are available, including the use of record bases with wax rims, bite blocks with temporary abutments and pattern resin, or provisional prostheses.Among these, using provisional prostheses directly for mounting on the master model can help minimize errors during the jaw relation recording phase. The patient in this case was a 55-year-old female patient, who presented for implant-supported fixed prosthetic rehabilitation. She exhibited multiple tooth loss due to periodontal disease, necessitating comprehensive mouth rehabilitation involving extractions and implant placements. After evaluating esthetics and occlusion with provisional prostheses, the same provisional prostheses were used for mounting on the master model, which enabled the fabrication of customized implant abutments and zirconia prostheses. The final result was a successful restoration, both esthetically and functionally.

The restoration process for patients with collapsed occlusion or those requiring extensive rehabilitation often involves various trials and errors. Accurately transferring the patient’s oral information to the articulator is key to producing esthetically pleasing and stable prostheses. This necessitates precise master model fabrication and accurate jaw relation records. For patients undergoing extensive implant-supported fixed prostheses, several techniques for recording the jaw relationship are available, including the use of record bases with wax rims, bite blocks with temporary abutments and pattern resin, or provisional prostheses.Among these, using provisional prostheses directly for mounting on the master model can help minimize errors during the jaw relation recording phase. The patient in this case was a 55-year-old female patient, who presented for implant-supported fixed prosthetic rehabilitation. She exhibited multiple tooth loss due to periodontal disease, necessitating comprehensive mouth rehabilitation involving extractions and implant placements. After evaluating esthetics and occlusion with provisional prostheses, the same provisional prostheses were used for mounting on the master model, which enabled the fabrication of customized implant abutments and zirconia prostheses. The final result was a successful restoration, both esthetically and functionally.