An evaluation of patient experience before and after elective colectomy for diverticulitis between patients older and younger than 65 years: A pilot feasibility study in mobile health use.

BACKGROUND: Mobile health (mHealth) platforms are being used to understand patient-reported experiences before and after surgery. Currently, there is limited literature describing the feasibility of using mHealth to evaluate patient experience among older adults. The objective of this study was to determine the feasibility of using mHealth to evaluate patient-reported outcomes among patients older and younger than 65 years undergoing elective colectomy for diverticulitis. METHODS: A prospective pilot study was performed between June 1, 2020 and August 31, 2021, enrolling patients aged > 18 years undergoing elective colectomy for diverticulitis at a single academic center (n = 62). A Health Insurance Portability and Accountability Act-compliant mHealth platform was used to deliver patient-reported quality-of-life surveys at 3 time points: preoperatively, 3 months postoperatively, and 6 months postoperatively. The primary outcome was the feasibility of using mHealth in patients older and younger than 65 years to collect outcomes using recruitment, engagement, and survey completion rates. Preliminary findings of patient experiences were evaluated for patients older and younger than 65 years as secondary outcomes. RESULTS: Overall, 33.9% of participants were older than 65 years with a median age of 59.8 years (IQR, 53.3-67.9). mHealth enrollment was high (100%) with survey response rates of 79% preoperatively, 64.5% at 3 months postoperatively, and 17.7% at 6 months postoperatively. Response rates were similar among patients older and younger than 65 years (P = .79 preoperatively and P = .39 at 3 months postoperatively). CONCLUSION: Utilization of mHealth to evaluate patient-reported outcomes is feasible in the preoperative and early postoperative settings, including older adults undergoing elective surgery for diverticulitis. Future work will focus on improving long-term outcomes to better examine potential differences when considering patient-centered outcomes among older adult patients.

A Digital Communication Intervention to Support Older Adults and Their Care Partners Transitioning Home After Major Surgery: Protocol for a Qualitative Research Study.

BACKGROUND: Older adults (aged ≥65 years) account for approximately 30% of inpatient procedures in the United States. After major surgery, they are at high risk of a slow return to their previous functional status, loss of independence, and complications like delirium. With the development and refinement of Enhanced Recovery After Surgery protocols, older patients often return home much earlier than historically anticipated. This put a larger burden on care partners, close family or friends who partner with the patient and guide them through recovery. Without adequate preparation, both patients and their care partners may experience poor long-term outcomes. OBJECTIVE: This study aimed to improve and streamline recovery for patients aged ≥65 years by exploring the communication needs of patients and their care partners. Information from this study will be used to inform an intervention developed to address these needs and define processes for its implementation across surgical clinics. METHODS: This qualitative research protocol has two aims. First, we will define patient and care partner needs and perspectives related to digital health innovation. To achieve this aim, we will recruit dyads of patients (aged ≥65 years) who underwent elective major surgery 30-90 days prior and their respective care partners (aged ≥18 years). Participants will complete individual interviews and surveys to obtain demographic data, characterize their perceptions of the surgical experience, identify intervention targets, and assess for the type of intervention modality that would be most useful. Next, we will explore clinician perspectives, tools, and strategies to develop a blueprint for a digital intervention. To achieve this aim, clinicians (eg, geriatricians, surgeons, and nurses) will be recruited for focus groups to identify current obstacles affecting surgical outcomes for older patients, and we will review current assessments and tools used in their clinical practice. A hybrid deductive-inductive approach will be undertaken to identify relevant themes. Insights from both clinicians and patient-care partners will guide the development of a digital intervention strategy to support older patients and their care partners after surgery. RESULTS: This study has been approved by the Massachusetts General Hospital and Harvard Institutional Review Boards. Recruitment began in December 2023 for the patient and care partner interviews. As of August 2024, over half of the interviews have been performed, deidentified, and transcribed. Clinician recruitment is ongoing, with no focus groups conducted yet. The study is expected to be completed by fall 2024. CONCLUSIONS: This study will help create a scalable digital health option for older patients undergoing major surgery and their care partners. We aim to enhance our understanding of patient recovery needs; improve communication with surgical teams; and ultimately, reduce the overall burden on patients, their care partners, and health care providers through real-time assessment. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/59067.

Implementing mobile health in your surgical practice: Results of a multidisciplinary convening.

The perioperative journey remains complex and difficult to navigate for patients and caregivers. Poor communication and lack of care coordination lead to diminished patient satisfaction, outcomes, and system performance. Mobile health platforms have the potential to overcome some of these issues by improving care delivery through timely individualized assessments, improved patient education, and care coordination. Yet mobile health implementation in surgical practice remains limited. Based on a convening of experts using human-centered design techniques, an implementation guide for the integration of mobile health in perioperative care was created to assist with (1) identification of the use of mobile health within a specific surgical practice, (2) identification of the pathway to mobile health implementation, and (3) measurement of successful implementation including patient and surgical system impact. This article reviews those recommendations and provides references to additional literature, including the full implementation guide, to aid those seeking to implement mobile health in a surgical practice or system.

Geriatric Assessment in Colorectal Surgery: A Systematic Review.

INTRODUCTION: The prevalence of colorectal surgery among older adults is expected to rise due to the aging population. Geriatric conditions (e.g., frailty) are risk factors for poor surgical outcomes. The goal of this systematic review is to examine how current literature describes geriatric assessment interventions in colorectal surgery and associated outcomes. METHODS: Systematic searches of Ovid MEDLINE, Cochrane Library, CINAHL, Embase, and Web of Science were completed. Review was performed according to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines and prospectively registered in PROSPERO, the international prospective register of systematic reviews in health and social care. All cohort studies and randomized trials of adult colorectal surgery patients where geriatric assessment was performed were included. Geriatric assessment with/without management interventions were identified and described. RESULTS: Seven-hundred ninety-three studies were identified. Duplicates (197) were removed. An additional 525 were excluded after title/abstract review. After full-text review, 20 studies met the criteria. Reference list review increased final total to 25 studies. All 25 studies were cohort studies. No randomized clinical trials were identified. Heterogeneous assessments were organized into geriatrics domains (mind, mobility, medications, matters most, and multi-complexity). Incomplete evaluations across geriatric domains were performed with few studies describing the use of assessments to impact management decisions. CONCLUSIONS: There are no randomized trials assessing the impact of geriatric assessment to tailor management strategies and improve outcomes in colorectal surgery. Few studies performed assessments to evaluate the geriatric domain matters most. These findings represent a gap in evidence for the efficacy of geriatric assessment and management strategies in colorectal surgical care.

Causes of death in patients operated for colorectal cancer.

BACKGROUND: Colorectal cancer remains the third leading cause of cancer-related mortality in the United States. This study evaluates the causes of death in patients operated on for colorectal cancer and their determinants. METHODS: An Instructional Review Board-approved database containing patients who underwent surgical resection for colorectal cancer from 2004 to 2018 (last followed up in December 2020) in a tertiary care institution. Data on the underlying cause of death was extracted from the Registry of Vital Records and Statistics in Massachusetts. RESULTS: A total of 576 deaths were recorded in the database, of which 290 (50.35%) patients died of colorectal cancer. Deaths from colorectal cancer gradually decreased over time, whereas deaths from other cancers increased, and deaths from cardiovascular diseases remained stable. Patients who died from colorectal cancer were younger, died earlier in the disease course, had fewer comorbidities, higher rates of stage IV disease, rectal cancer, neoadjuvant therapy, extramural vascular invasion, perineural invasion, R0 resection, and preserved mismatch repair protein status. On multivariate analysis, age (adjusted odds ratio for 10-year increase = 0.79, 95% confidence interval 0.65-0.95), American Society of Anesthesiologists score (adjusted odds ratio = 0.64, confidence interval 0.42-0.98), stage IV disease (adjusted odds ratio = 3.02, confidence interval 1.59-5.9), neoadjuvant therapy (adjusted odds ratio = 7.91, confidence interval 2.64-28.13), extramural vascular invasion (adjusted odds ratio = 2.3, confidence interval 1.36-3.91) & time from diagnosis to death (adjusted odds ratio = 0.76, confidence interval 0.68-0.83) predicted death due to colorectal cancer versus other causes, whereas tumor location, perineural invasion, R0 resection, and mismatch repair protein status did not. CONCLUSION: There is a declining trend of deaths from colorectal cancer, presumably reflecting advances in colorectal cancer management strategies and better screening over time. However, younger patients disproportionately contribute to death due to colorectal cancer and need aggressive screening and management strategies.

Mobile health in the aging surgical patient.

Mobile health includes the use of mobile devices, patient monitoring devices, and digital assistants to improve the delivery of healthcare. Aging surgical patients (ie, 65 years and older) represent a unique patient population that demands increased resources to prepare for surgery and optimize recovery. Mobile health has the potential to improve surgical patient outcomes by increasing the accessibility of personalized care and reducing costs. However, there are some challenges to consider when using mobile health in older surgical patients, such as technological literacy, visual and hearing impairment, and cognitive changes before or after anesthesia. Despite the rapid uptake of mobile health in medical specialties, its application in the surgical field is gradual. The complexity of aging surgical patients requires surgical care teams, surgical leaders, and healthcare policymakers to consider unique solutions, such as mobile health, to address this growing population's needs before and after surgery. This article will discuss the potential benefits and challenges of mobile health among aging surgical patients, as well as opportunities to support these patients and families with customizable tools to meet their preferences and needs.

Incidence of Secondary Cancers After Neoadjuvant Therapy for Locally Advanced Rectal Cancer.

INTRODUCTION: Whether neoadjuvant chemoradiation for locally advanced rectal cancer (LARC) induces secondary cancers is controversial. This retrospective cohort study describes the incidence of secondary cancers in LARC patients. METHODS: We compared 364 LARC patients who received conventional (50.4 Gy) or short course neoadjuvant radiation (25 Gy x 5 fractions) followed by resection to 142 patients with surgically resected rectal cancer who did not receive radiation at a single institution from 2004 to 2018. Secondary cancer was defined as any nonmetastatic noncolorectal malignancy diagnosed via biopsy or definitive imaging criteria at least 6 mo after completion of neoadjuvant therapy or after resection in the comparison group. RESULTS: Among the neoadjuvant radiation group (364 patients, 40% female, age 61 ± 13 y), 32 patients developed 34 (9.3%) secondary cancers. Three cases involved a pelvic organ. Among the comparison group (142 patients, 39% female, age 64 ± 15 y), 15 patients (10.6%) developed a secondary cancer. Five cases involved pelvic organs. Secondary cancer incidence did not differ between groups. Latency period to secondary cancer diagnosis was 6.7 ± 4.3 y. Patients who received radiation underwent longer median follow-up (6.8 versus 4.5 y, P < 0.01) and were significantly less likely to develop a pelvic organ cancer (odds ratio 0.18; 95% confidence interval, 0.04-0.83; P = 0.02). No genetic mutations or cancer syndromes were identified among patients with secondary cancers. CONCLUSIONS: Neoadjuvant chemoradiation is not associated with increased secondary cancer risk in LARC patients and may have a local protective effect on pelvic organs, especially prostate. Ongoing follow-up is critical to continue risk assessment.

Metformin Does not Affect Outcomes in Patients With Locally Advanced Rectal Cancer Treated With Neoadjuvant Therapy and Resection.

INTRODUCTION: There is emerging evidence that metformin may have a protective effect in patients with cancer. However, its current evidence in locally advanced rectal cancer (LARC) is inconclusive. We aim to assess the effect of metformin on long-term outcomes in patients with LARC who received neoadjuvant therapy and surgical resection. METHODS: A retrospective review of 324 patients with nonmetastatic LARC who received neoadjuvant therapy and major surgical resection from 2004 to 2018. There were 27 patients who received metformin before surgery and 297 patients who did not receive metformin. RESULTS: Metformin users were associated with a significantly higher age, BMI, ASA score, and 30-day readmissions (P < .05). There was no difference in overall survival (OS, P = .18) or disease-free survival (DFS, P = .33) between the two groups. On Cox regression, metformin intake did not predict OS (HR 0.85, 95% CI 0.4-1.77) when controlled for age (HR 1.04, 1.02-1.06), sex (HR 1.13, 0.69-1.85), BMI (HR 0.97, 0.92-1.02), ASA score (HR: 1.7, 1.06-2.73), TNT (HR 0.31, 0.1-0.92), pathological Stage III disease (HR 2.55, 1.51-4.32), extramural vascular invasion (EMVI) (HR 3.06, 1.7-5.5), and adjuvant therapy (HR 0.1, 0.04-0.27 for <25 months OS and HR 0.3, 0.15-0.59 for ≥25 months). Disease-free survival showed a similar trend with no significant effect of metformin (HR 0.77, 0.39-1.52) when controlled for age, sex, BMI, ASA, TNT, Stage III disease, EMVI, and adjuvant therapy. CONCLUSION: Metformin does not affect long-term survival in LARC treated with neoadjuvant therapy followed by surgical resection. Studies with larger sample sizes are needed to validate the findings further.

Patient Factors Affecting Inpatient Mortality Following Colorectal Cancer Resection.

BACKGROUND: Our objective is to identify factors for inpatient death in patients undergoing resection for colorectal cancer (CRC). STUDY DESIGN: Unmatched 1:3 case-control study of surgically resected CRC at a tertiary care institution between 2004 and 2018. Variables for multivariate analysis were selected using tetrachoric correlation followed by a least absolute shrinkage and selection operator (LASSO) penalized regression model. RESULTS: A total of 140 patients were included (N = 35 patients who died inpatient, N = 105 patients who did not die). Patients who died were older, had higher Charlson Comorbidity Index (CCI), higher rates of preoperative anemia, hypoalbuminemia, emergency surgeries, blood transfusion, postoperative vasopressor requirement, anastomotic leak, and postoperative ICU admission than patients who underwent surgical resection without inpatient mortality. Anemia (aOR = 8.62, 1.44-91.58), emergency admission (aOR = 5.71, 1.46-24.36), and ICU admission (aOR 45.51, 8.31-448.4) significantly predicted inpatient mortality when controlled for CCI and hypoalbuminemia. CONCLUSIONS: Surprisingly, it appears that pre-existing anemia and perioperative factors are more important in predicting inpatient mortality of patients undergoing CRC surgery than baseline comorbidity or nutritional status.

Colitis-Associated Colorectal Cancer Survival is Comparable to Sporadic Cases after Surgery: a Matched-Pair Analysis.

BACKGROUND: Inflammatory bowel disease (IBD) confers an increased lifetime risk of colorectal cancer (CRC). The pathogenesis of colitis-associated CRC is considered distinct from sporadic CRC, but existing is mixed on long-term oncologic outcomes. This study aims to compare clinicopathological characteristics and survival between colitis-associated and sporadic CRC. METHODS: Data was retrospectively extracted and analyzed from a single institutional database of patients with surgically resected CRC between 2004 and 2015. Patients with IBD were identified as having colitis-associated CRC. The remainder were classified as sporadic CRC. Propensity score matching was performed. Univariate and survival analyses were carried out to estimate the differences between the two groups. RESULTS: Of 2275 patients included in this analysis, 65 carried a diagnosis of IBD (2.9%, 33 Crohn's disease, 29 ulcerative colitis, 3 indeterminate colitis). Average age at CRC diagnosis was 62 years for colitis-associated CRC and 65 for sporadic CRC. The final propensity score matched cohort consisted of 65 colitis-associated and 130 sporadic CRC cases. Patients with colitis-associated CRC were more likely to undergo total proctocolectomy (p < 0.01) and had higher incidence of locoregional recurrence (p = 0.026) compared to sporadic CRC patients. There were no significant differences in time to recurrence, tumor grade, extramural vascular invasion, perineural invasion, or rate of R0 resections. Overall survival and disease-free survival did not differ between groups. On multiple Cox regression, IBD diagnosis was not a significant predictor of survival. CONCLUSIONS: Patients with colitis-associated CRC who undergo surgical resection have comparable overall and disease-free survival to patients with sporadic CRC.

Association of age with outcomes in locally advanced rectal cancer treated with neoadjuvant therapy followed by surgery.

INTRODUCTION: We aimed to assess the association of age with outcomes in patients with Locally Advanced Rectal Cancer (LARC) who received neoadjuvant therapy followed by major surgery. METHODS: Retrospective review of 328 patients with LARC, N = 99 < 70 years (younger) versus N = 229 ≥ 70 years (elderly) from 2004 to 2018. RESULTS: Elderly patients had a higher American Society of Anesthesiologists (ASA) score, Charlson Comorbidity Index (CCI), length of stay and 30-day readmissions (p < 0.05). They also had worse overall survival (OS) & disease-free survival (DFS) (p < 0.001), but similar disease-specific survival (DSS) compared to younger group. Age was not associated with hazard of death (HR 1.01, 0.98-1.03). Rather, CCI (HR 1.29, 1.01-1.5), extramural vascular invasion (HR 4.98, 2.84-8.74), and adjuvant therapy (0.37, 0.21-0.64) were significantly associated with the hazard of death; when controlled for stage, tumor distance from anal verge, and neoadjuvant completion. CONCLUSION: Comorbidities and lower rates of adjuvant therapy, and not chronologic age, are associated with poor OS of elderly patients with LARC treated with neoadjuvant therapy and major surgery.

The time Interval Between the End of Radiotherapy and Surgery Does Not Affect Outcomes in Rectal Cancer.

INTRODUCTION: The ideal time interval between the completion of chemoradiotherapy and subsequent surgical resection of advanced stage rectal tumors is highly debated. Our aim is to study the effect of the time interval between the completion of chemoradiotherapy and surgical resection on postoperative and oncologic outcomes in rectal cancer. METHODS: Patients who underwent neoadjuvant chemoradiotherapy for resected locally advanced rectal tumors between 2004 and 2015 were included in this analysis. The time interval was calculated from the date of radiation completion to date of surgery. Patients were split into 2 groups based on the time interval (<8 weeks and >8 weeks). Postoperative outcomes (anastomotic leak, pathologic complete response (pCR), and readmission) and survival were assessed with multivariable logistic regression and Cox regression models while adjusting for relevant confounders. RESULTS: 200 patients (62% male) underwent resection with a median time interval of 8 weeks from completion of radiotherapy. On multivariable logistic regression, there was no significant increase in odds between time interval to surgery and anastomotic leak (aOR = .8 [.27-2.7], P = .8), pCR (aOR = 1.2[.58-2.6] P = .6), or readmission (aOR = 1.02, 95% CI:0.49-2.24, P = .9). Time interval to surgery was not an independent prognostic factor for overall (HR = 1.04 CI = .4-2.65, P = .9) and disease-free survival (HR = 1.2 CI = .5-2.9, P = .6). CONCLUSION: The time interval between neoadjuvant radiotherapy completion and surgical resection does not affect anastomotic leak rate, achievement of pCR, or overall and disease-free survival in patients with rectal cancer. Extended periods of time to surgical resection are relatively safe.

Perceptions of Mobile Health Technology in Elective Surgery: A Qualitative Study of North American Surgeons.

OBJECTIVES: To explore the surgeon-perceived added value of mobile health technologies (mHealth), and determine facilitators of and barriers to implementing mHealth. BACKGROUND: Despite the growing popularity of mHealth and evidence of meaningful use of patient-generated health data in surgery, implementation remains limited. METHODS: This was an exploratory qualitative study following the Consolidated Criteria for Reporting Qualitative Research. Purposive sampling was used to identify surgeons across the United States and Canada. The Consolidated Framework for Implementation Research informed development of a semistructured interview guide. Video-based interviews were conducted (September-November 2020) and interview transcripts were thematically analyzed. RESULTS: Thirty surgeons from 8 specialties and 6 North American regions were interviewed. Surgeons identified opportunities to integrate mHealth data pre- operatively (eg, expectation-setting, decision-making) and during recovery (eg, remote monitoring, earlier detection of adverse events) among higher risk patients. Perceived advantages of mHealth data compared with surgical and patient-reported outcomes included easier data collection, higher interpretability and objectivity of mHealth data, and the potential to develop more patientcentered and functional measures of health. Surgeons identified a variety of implementation facilitators and barriers around surgeon- and patient buy-in, integration with electronic medical records, regulatory/reimbursement concerns, and personnel responsible for mHealth data. Surgeons described similar considerations regarding perceptions of mHealth among patients, including the potential to address or worsen existing disparities in surgical care. CONCLUSIONS: These findings have the potential to inform the effective and equitable implementation of mHealth for the purposes of supporting patients and surgical care teams throughout the delivery of surgical care.

Molecular Basis of Extramural Vascular Invasion (EMVI) in Colorectal Carcinoma.

BACKGROUND: Extramural vascular invasion (EMVI) is a known poor prognostic factor in colorectal carcinoma; however, its molecular basis has not been defined. This study aimed to assess the expression of molecular markers in EMVI positive colorectal carcinoma to understand their tumor microenvironment. METHODS: Immunohistochemistry was performed on tissue microarrays of surgically resected colorectal cancer specimens for immunological markers, and BRAFV600E mutation (and on the tissue blocks for mismatch repair proteins). Automated quantification was used for CD8, LAG3, FOXP3, PU1, and CD163, and manual quantification was used for PDL1, HLA I markers (beta-2 microglobulin, HC10), and HLA II. The Wilcoxon rank-sum test was used to compare EMVI positive and negative tumors. A logistic regression model was fitted to assess the predictive effect of biomarkers on EMVI. RESULTS: There were 340 EMVI positive and 678 EMVI negative chemo naïve tumors. PDL1 was barely expressed on tumor cells (median 0) in the entire cohort. We found a significantly lower expression of CD8, LAG3, FOXP3, PU1 cells, PDL1 positive macrophages, and beta-2 microglobulin on tumor cells in the EMVI positive subset (p ≤ 0.001). There was no association of BRAFV600E or deficient mismatch repair proteins (dMMR) with EMVI. PU1 (OR 0.8, 0.7-0.9) and low PDL1 (OR 1.6, 1.1-2.3) independently predicted EMVI on multivariate logistic regression among all biomarkers examined. CONCLUSION: There is a generalized blunting of immune response in EMVI positive colorectal carcinoma, which may contribute to a worse prognosis. Tumor-associated macrophages seem to play the most significant role in determining EMVI.

Multi-institutional Cohort Study of Elective Diverticulitis Surgery: a National Surgical Quality Improvement Program Database Analysis to Identify Predictors of Non-home Discharge Among Older Adults.

BACKGROUND: Older adults often prioritize independence and time spent at home when making major treatment decisions. Identifying preoperative predictors of non-home discharge (i.e., requiring institutional discharge rather than home), among adults undergoing elective diverticulitis surgery, can support surgical decision-making and expectation management. This study aims to (1) examine rates of non-home discharge after elective surgery for diverticulitis and (2) identify predictors of non-home discharge. METHODS: This is a multi-institutional cohort study of National Surgical Quality Improvement Program Database. Patients over 18 years who underwent colon resection with diagnosis of diverticulitis were included. Clinical and demographic information were collected by trained nurse reviewers. Emergency operations were excluded. Patients with home versus non-home discharge were compared and predictors identified using multivariable regression. RESULTS: Between 2016 and 2019, 40,912 patients were identified. Mean age was 58.5 years (SD = 12.58) with 48.5% 60 + years and 17.7% of patients 70 + years old. The majority (55.9%) were female and "White" race (83.5%). Most patients underwent colectomy without ostomy (88.4%). Nine percent of patients over age 60 had non-home discharge. Functional dependence preoperatively was strongly associated with non-home discharge. On multivariable analysis, significant predictors of non-home discharge were preoperative functional dependence (OR 28.2; 95% CI 9.8-81.7), advancing chronologic age (age 80 + : OR 22.4; 95% CI 18.6-26.9), and preoperative albumin < 3.0 (OR 4.0; 95% CI 3.4-4.6). CONCLUSIONS: Nearly one in ten patients over 60 years was not discharged home after elective diverticulitis surgery. Preoperative functional status predicts non-home discharge. Future studies need to assess potentially modifiable causes of non-home discharge, such as social support.

Tumour genotypes account for survival differences in right- and left-sided colon cancers.

AIM: We sought to identify genetic differences between right- and left-sided colon cancers and using these differences explain lower survival in right-sided cancers. METHOD: A retrospective review of patients diagnosed with colon cancer was performed using The Cancer Genome Atlas, a cancer genetics registry with patient and tumour data from 20 North American institutions. The primary outcome was 5-year overall survival. Predictors for survival were identified using directed acyclic graphs and Cox proportional hazards models. RESULTS: A total of 206 right- and 214 left-sided colon cancer patients with 84 recorded deaths were identified. The frequency of mutated alleles differed significantly in 12 of 25 genes between right- and left-sided tumours. Right-sided tumours had worse survival with a hazard ratio of 1.71 (95% confidence interval 1.10-2.64, P = 0.017). The total effect of the genetic loci on survival showed five genes had a sizeable effect on survival: DNAH5, MUC16, NEB, SMAD4, and USH2A. Lasso-penalized Cox regression selected 13 variables for the highest-performing model, which included cancer stage, positive resection margin, and mutated alleles at nine genes: MUC16, USH2A, SMAD4, SYNE1, FLG, NEB, TTN, OBSCN, and DNAH5. Post-selection inference demonstrated that mutations in MUC16 (P = 0.01) and DNAH5 (P = 0.02) were particularly predictive of 5-year overall survival. CONCLUSIONS: Our study showed that genetic mutations may explain survival differences between tumour sites. Further studies on larger patient populations may identify other genes, which could form the foundation for more precise prognostication and treatment decisions beyond current rudimentary TNM staging.