Patients
From 2015 to 2021, a total of 165 elderly patients participated in the GMOC at Seoul National University Bundang Hospital Comprehensive Cancer Center. Of these patients, we analyzed 74 patients who had colorectal cancer.
GMOC
The GMOC makes decisions with patients and their families based on CGA, multidimensional frailty score (MFS) data and experts opinion. The GMOC held weekly meetings to discuss elderly patients who met with surgeons, radiation oncologists, medical oncologists, radiologists, and geriatricians to establish a treatment plan. In each department, the decision about the type of treatment to be given to elderly patients with colorectal cancer was marked as a “decision,” and the treatment plan decided upon after the GMOC meeting was marked as a “recommendation.” When a patient actually underwent the treatment, it was marked as “actually performed.” The clinical adherence rate was defined as the ratio of “actually performed” to “decision.”
CGA
CGA is a systematic assessment tool for geriatric patients, including comorbidities, physical function, nutrition, polypharmacy, psychological status, and risk of postoperative delirium [7]. Comorbidities were estimated using the Charlson Comorbidity Index (CCI) consisting of 19 comorbidity categories; weights were assigned to each category based on the adjusted relative risk of 1-year mortality, and all individual weights were summed to calculate a single comorbidity score for each patient [10]. Physical function was evaluated based on activities of daily living (ADL) and instrumental ADL (IADL). ADL was evaluated using the modified Barthel Index, which includes 10 subscales: grooming, eating, bathing, toilet use, dressing, fecal and urinary continence, walking in a hallway, and the ability to go up and down stairs [11]. IADL was evaluated using the Lawton and Brody Index, which includes five subscales for men: shopping, ability to use telephone, responsibility for own medication, traveling via public transportation or car, and financial management. For women, three additional items were also included (housekeeping, food preparation, and laundry) [12]. Nutrition was assessed using the Mini Nutritional Assessment (MNA), with scores ranging from 0 to 30; scores below 17 indicated malnutrition [13]. A diagnosis of polypharmacy was determined through a thorough medical review and detailed history of the patient. Polypharmacy was defined as taking more than five medications on a regular basis, and inappropriate medications were determined using the Beers criteria [14]. The Korean version of the Mini-Mental State Examination (MMSE-KC) was used to evaluate psychological status, with scores ranging from 0 to 30. Scores ranging between 17 and 24 indicate mild cognitive impairment, whereas those less than 17 indicate dementia [15]. To screen for depressive symptoms, a short form of the Korean Geriatric Depression Scale was used to score between 0 and 15; a score of 10 or higher was considered severe depression [16]. The Nursing Delirium Screening Scale, with scores ranging from 0 to 5, was used to assess the risk of postoperative delirium. A score ≥ 2 indicates an increased risk of postoperative delirium [17].
MFS
The MFS consists of 9 items: malignant disease, CCI, albumin, ADL, IADL, MMSE-KC, risk of delirium, MNA, and midarm circumference. Each item is scored from 0 to 2, and patients are classified into the high-risk group when 5 points are exceeded. This is more useful for predicting the outcome of geriatric patients undergoing surgery than conventional methods [8].
Outcome measures
The factors that influenced the decision to recommend surgery in the GMOC and the 1-year survival outcomes were investigated by comparing the groups that were and were not recommended for surgery. We also compared the 1-year survival outcomes between patients who underwent surgery and those who did not. In the group that underwent surgery, we analyzed the operation time, estimated blood loss, hospital stay, postoperative complications, and re-admission within 30 days.
Statistical analysis
Categorical variables are presented as numbers (percentages) and continuous variables as medians (interquartile ranges). Fisher’s exact test or the chi-square test was used to compare categorical variables, while the Mann–Whitney U test was used to compare continuous variables. The 1-year overall survival (OS) was calculated using the Kaplan–Meier analysis. The OS was calculated from the date of diagnosis to the date of death. Statistical significance was set at p < 0.05. All statistical analyses were performed using MedCalc version 20 (MedCalc Software, Ostend, Belgium) and IBM SPSS Statistics version 22 (IBM Corp., Armonk, NY, USA). The institutional review board of our hospital approved this study before the commencement of data collection and analysis (IRB no.: B-2201-733-105), and the need for informed consent was waived.