Impact of age on the use of adjuvant treatments in patients undergoing surgery for colorectal cancer: patients with stage III colon or stage II/III rectal cancer

Survival prognostic in different age groups of patients undergoing local versus radical excision for rectal cancer: a study based on the SEER database

Age significantly affects the prognosis of patients with rectal cancer after radical excision (RE), and local excision (LE) is an alternative surgical procedure to RE. To compare the survival prognosis in different age groups of LE versus RE for rectal cancer. Patients diagnosed with rectal adenocarcinoma treated by LE or RE from 2010 to 2017 were obtained from the SEER database. The primary outcomes are 5-year OS and CSS. A total of 11,170 patients were eventually included, and there were 490 patients in LE and RE groups, respectively, after 1:1 propensity score matching. The 5-year OS and CSS after LE were significantly better in < 50 years and 50-66 years groups than in > 66 years group (5-year OS: 95.70% vs 88.40% vs 67.00%, P < 0.001; 5-year CSS: 95.70% vs 96.30% vs 82.60%, P < 0.001). No statistical significance was found for the differences in 5-year OS and CSS between LE and RE in < 50, 50-66, and > 66 years group (P > 0.05). Multivariate analysis showed age > 66 years, poorly differentiated or undifferentiated (Grade III/IV), and tumor size 3 to 5 cm was independent risk factors for 5-year OS after LE; age > 66 years, perineural invasion, and tumor size 3 to 5 cm were the 5-year CSS independent risk factors for after LE. We found that the survival prognosis of younger rectal cancer patients treated with LE was significantly better than older (> 66 years) patients, and the survival prognosis of rectal cancer patients in the three age groups was similar between LE and RE.

Carbohydrate polymers-based surface modified nano delivery systems for enhanced target delivery to colon cancer - A review

Carbohydrate polymers-based surface-modified nano-delivery systems have gained significant attention in recent years for enhancing targeted delivery to colon cancer. These systems leverage carbohydrate polymers' unique properties, such as biocompatibility, biodegradability, and controlled release. These properties make them suitable candidates for drug delivery applications. Nano-delivery systems loaded with bioactive compounds are well-studied for targeted colorectal cancer delivery. However, those drugs' target reach is still limited in various nano-delivery systems. To overcome this limitation, surface modification of nanoparticles with carbohydrate polymers like chitosan, pectin, alginate, and guar gum showed enhanced target-reaching capacity along with enhanced anticancer efficacy. Recently, a chitosan-decorated PLGA nanoparticle was constructed with tannic acid and vitamin E and showed long-term release of specific targets along with higher anticancer efficacy. Similarly, Chitosan-conjugated glucuronic acid-coated silica nanoparticles loaded with capecitabine were studied against colon cancer and found to be the pH-responsive controlled release of capecitabine with higher anticancer efficacy. Surface-modified carbohydrate polymers have promising potential for improving colon cancer target delivery. By leveraging the unique properties of these polymers, such as surface modification, pH responsiveness, mucoadhesion, controlled drug release, and combination therapy, researchers are working toward developing more effective and targeted treatment strategies for colon cancer.

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.

Treatment paradigm and prognostic factor analyses of rectal squamous cell carcinoma

Background

Rectal squamous cell carcinoma (rSCC) is a rare pathological subtype of rectal cancer. There is no consensus on the treatment paradigm for patients with rSCC. This study aimed to provide a paradigm for clinical treatment and develop a prognostic nomogram.

Methods

Patients diagnosed with rSCC between 2010 and 2019 were identified in the Surveillance, Epidemiology, and End Results (SEER) database. According to the TNM staging system, Kaplan-Meier (K-M) survival analysis was used to identify the survival benefits of different treatments in patients with rSCC. The Cox regression method was used to identify independent prognostic risk factors. Nomograms were evaluated by Harrell's concordance index (C-index), calibration curves, decision curve analysis (DCA) and K-M curves.

Results

Data for 463 patients with rSCC were extracted from the SEER database. Survival analysis showed that there was no significant difference in median cancer-specific survival (CSS) among patients with TNM stage 1 rSCC treated with radiotherapy (RT), chemoradiotherapy (CRT) or surgery (P = 0.285). In TNM stage 2 patients, there was a significant difference in median CSS among those treated with surgery (49.5 months), RT (24 months), and CRT (63 months) (P = 0.003). In TNM stage 3 patients, there was a significant difference in median CSS among those treated with CRT (58 months), CRT plus surgery (56 months) and no treatment (9.5 months) (P < 0.001). In TNM stage 4 patients, there was no significant difference in median CSS among those treated with CRT, chemotherapy (CT), CRT plus surgery and no treatment (P = 0.122). Cox regression analysis showed that age, marital status, T stage, N stage, M stage, PNI, tumor size, RT, CT, and surgery were independent risk factors for CSS. The 1-, 3-, and 5-year C-indexes were 0.877, 0.781, and 0.767, respectively. The calibration curve showed that the model had excellent calibration. The DCA curve showed that the model had excellent clinical application value.

Conclusion

RT or surgery is recommended for patients with stage 1 rSCC, and CRT is recommended for patients with stage 2, and stage 3 rSCC. Age, marital status, T stage, N stage, M stage, PNI, tumor size, RT, CT, and surgery are independent risk factors for CSS in patients with rSCC. The model based on the above independent risk factors has excellent prediction efficiency.

Variations in colorectal cancer pattern of care by age and comorbidity in South Australia

BACKGROUND

Advanced age is associated with decreased likelihood of colorectal cancer treatment. Here, we investigated the extent to which comorbidities are accountable for this lesser treatment.

METHODS

Using population-based datasets, the pattern of care among CRC cases in South Australia during 2004-2013 was investigated. Models were used to investigate associations of age with each treatment type, and differences in these associations were explored by comorbidity and cancer site.

RESULTS

The presence of comorbidity was associated with a significantly weaker relationship of age with surgery and chemotherapy. The association of age with surgery also varied for colon and rectal primary cancer sites. Individual comorbidity types varied in their associations with each treatment category. For example, dementia was associated with less chemotherapy provision, however, it was not significantly related to the likelihood of surgery.

CONCLUSION

This study indicates that the association of age with surgical treatment differed significantly by the CRC subsite. Comorbidity moderated the negative association of age with chemotherapy, and less so, with extent of surgery. Results were novel in indicating associations of multiple individual comorbidity types with CRC treatment modalities. The data suggest that different individual comorbidity types may have different effects on treatment and should be studied separately.

Age-related differences in cancer relative survival in the United States: A SEER-18 analysis

Cancer survival has improved since the 1990s, but to different extents across age groups, with a disadvantage for older adults. We aimed to quantify age-related differences in relative survival (RS-1-year and 1-year conditioning on surviving 1 year) for 10 common cancer types by stage at diagnosis. We used data from 18 United States Surveillance Epidemiology and End Results cancer registries and included cancers diagnosed in 2012 to 2016 followed until December 31, 2017. We estimated absolute differences in RS between the 50 to 64 age group and the 75 to 84 age group. The smallest differences were observed for prostate and breast cancers (1.8%-points [95% confidence interval (CI): 1.5-2.1] and 1.9%-points [95% CI: 1.5-2.3], respectively). The largest was for ovarian cancer (27%-points, 95% CI: 24-29). For other cancers, differences ranged between 7 (95% CI: 5-9, esophagus) and 18%-points (95% CI: 17-19, pancreas). Except for pancreatic cancer, cancer type and stage combinations with very high (>95%) or very low (<40%) 1-year RS tended to have smaller age-related differences in survival than those with mid-range prognoses. Age-related differences in 1-year survival conditioning on having survived 1-year were small for most cancer and stage combinations. The broad variation in survival differences by age across cancer types and stages, especially in the first year, age-related differences in survival are likely influenced by amenability to treatment. Future work to measure the extent of age-related differences that are avoidable, and identify how to narrow the survival gap, may have most benefit by prioritizing cancers with relatively large age-related differences in survival (eg, stomach, esophagus, liver and pancreas).

Variations in Patterns of Care of Rectal Cancer Patients in South Australia According to Sociodemographic Characteristics:A Registry Study

Objective. To explore variations in patterns of care over three decades for a subgroup of rectal cancer patients in South Australia according to sociodemographic characteristics. Methods. This study evaluated three decades of retrospective data from the South Australian Clinical Cancer Registry. A total of 4,131 patients diagnosed with rectal cancer between 1982 and 2015 and treated in South Australian public hospitals were included. Study outcomes were age at diagnosis, area of primary residence, cancer stage, and primary treatment (surgery, chemotherapy, or radiotherapy). Results. There was a significantly lower likelihood of conventional therapy for the elderly. Adjusted odds of receiving surgery or radiotherapy decreased by 70% and those of receiving chemotherapy by 90% in the 80+ age group, compared to the 50–59 age group. No significant variation was detected according to area-level socioeconomic status or remoteness. Conclusion. Socioeconomic factors showed little impact on the receipt of therapies for rectal cancer patients in South Australia. Variation in treatment by age, irrespective of disease stage or period of diagnosis, requires further investigation.

Trends in Adjuvant Chemotherapy Use Among Stage III Colon Cancer in Non-Elderly and Low Comorbidity Patients

BACKGROUND

Adjuvant chemotherapy for stage III colon cancer is underutilized in the United States. The aim of this study was to assess the use of adjuvant chemotherapy in younger and medically fit patients and analyze the socioeconomic factors associated with its utilization.

METHODS

Using the National Cancer Database from 2004 to 2015, we selected stage III colon cancer patients between age 18 to 65, Charlson-Deyo Comorbidity Index (CDCI) of 0 or 1, and those that survived at least 12 months after surgery. We then compared patients that underwent surgery only with those that received adjuvant chemotherapy. Multivariable logistic regression analysis was performed to identify variables associated with adjuvant chemotherapy use in the population. Overall survival was estimated by Kaplan-Meier curves.

RESULTS

Of the 48,336 patients that met inclusion criteria, 43,315 (90%) received adjuvant chemotherapy. The utilization of adjuvant chemotherapy increased from 87% in 2004 to 91% in 2015. On multivariable regression analysis, the use of adjuvant chemotherapy was lower among males, Non-Hispanic Blacks and Hispanics, low-grade cancer, left-sided tumors, CDCI 1, those who travel ≥ 50 miles, yearly income < $40,227, and uninsured patients. The most common reason for the omission of adjuvant chemotherapy was the patient or caregiver's choice (40% between 2013 and 2015). The 5-year and 10-year overall survival rates were 76.7% and 63.8% respectively, in those who received adjuvant chemotherapy as compared to 65.1% and 49.3% in those who underwent surgery only (P < .001).

CONCLUSION

In young and medically fit stage III colon cancer patients, most patients received guideline-compliant care in the United States. However, socioeconomic disparities adversely impacted the use of adjuvant chemotherapy. The patient or caregiver's decision was the most common reason for non-adherence to adjuvant chemotherapy and lead to poor survival outcomes. Emphasis should be placed on developing patient-centered strategies to improve adherence to chemotherapy in all patients.

Age disparities in stage-specific colon cancer survival across seven countries: An International Cancer Benchmarking Partnership SURVMARK-2 population-based study

We sought to understand the role of stage at diagnosis in observed age disparities in colon cancer survival among people aged 50 to 99 years using population-based cancer registry data from seven high-income countries: Australia, Canada, Denmark, Ireland, New Zealand, Norway and the United Kingdom. We used colon cancer incidence data for the period 2010 to 2014. We estimated the 3-year net survival, as well as the 3-year net survival conditional on surviving at least 6 months and 1 year after diagnosis, by country and stage at diagnosis (categorised as localised, regional or distant) using flexible parametric excess hazard regression models. In all countries, increasing age was associated with lower net survival. For example, 3-year net survival (95% confidence interval) was 81% (80-82) for 50 to 64 year olds and 58% (56-60) for 85 to 99 year olds in Australia, and 74% (73-74) and 39% (39-40) in the United Kingdom, respectively. Those with distant stage colon cancer had the largest difference in colon cancer survival between the youngest and the oldest patients. Excess mortality for the oldest patients with localised or regional cancers was observed during the first 6 months after diagnosis. Older patients diagnosed with localised (and in some countries regional) stage colon cancer who survived 6 months after diagnosis experienced the same survival as their younger counterparts. Further studies examining other prognostic clinical factors such as comorbidities and treatment, and socioeconomic factors are warranted to gain further understanding of the age disparities in colon cancer survival.

Oxaliplatin plus fluoropyrimidines as adjuvant therapy for colon cancer in older patients: A subgroup analysis from the TOSCA trial

BACKGROUND

Previous studies on oxaliplatin and fluoropyrimidines as adjuvant therapy in older patients with stage III colon cancer (CC) produced conflicting results.

PATIENTS AND METHODS

We assessed the impact of age on time to tumour recurrence (TTR), disease-free survival (DFS), cancer-specific survival (CSS), and overall survival (OS) in 2360 patients with stage III CC (1667 aged <70 years and 693 ≥ 70 years) randomised to receive 3 or 6 months of FOLFOX or CAPOX within the frame of the phase III, TOSCA study.

RESULTS

Older patients compared with younger ones presented more frequently an Eastern Cooperative Oncology Group performance status equal to 1 (10.5% vs 3.3%, p < 0.001), a greater number of right-sided tumours (40.9% vs 26.6%, p < 0.001), and were at higher clinical risk (37.2% vs 33.2%, p = 0.062). The treatments were almost identical in the two cohorts (p = 0.965). We found a greater proportion of dose reductions (46.7% vs 41.4%, p = 0.018), treatment interruptions (26.1% vs 19.3%, p < 0.001) and a higher proportion of recurrences (24.2% vs 20.3%, p = 0.033) in the older patients. The multivariable analysis of the TTR did not indicate a statistically significant effect of age (hazard ratio [HR]: 1.19; 95% confidence interval [CI]: 0.98-1.44; p = 0.082). The HR comparing older with younger patients was 1.34 (95% CI: 1.12-1.59; p = 0.001) for DFS, 1.58 (95% CI: 1.26-1.99; p < 0.001) for OS, and 1.28 (95% CI: 0.96-1.70; p = 0.089) for CSS.

CONCLUSIONS

Worse prognostic factors and reduced treatment compliance have a negative impact on the efficacy of oxaliplatin-based adjuvant therapy in older patients.

Patterns of age disparities in colon and lung cancer survival: a systematic narrative literature review

OBJECTIVES

To identify patterns of age disparities in cancer survival, using colon and lung cancer as exemplars.

DESIGN

Systematic review of the literature.

DATA SOURCES

We searched Embase, MEDLINE, Scopus and Web of Science through 18 December 2020.

ELIGIBILITY CRITERIA

We retained all original articles published in English including patients with colon or lung cancer. Eligible studies were required to be population-based, report survival across several age groups (of which at least one was over the age of 65) and at least one other characteristic (eg, sex, treatment).

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers extracted data and assessed the quality of included studies against selected evaluation domains from the QUIPS tool, and items concerning statistical reporting. We evaluated age disparities using the absolute difference in survival or mortality rates between the middle-aged group and the oldest age group, or by describing survival curves.

RESULTS

Out of 3047 references, we retained 59 studies (20 for colon, 34 for lung and 5 for both sites). Regardless of the cancer site, the included studies were highly heterogeneous and often of poor quality. The magnitude of age disparities in survival varied greatly by sex, ethnicity, socioeconomic status, stage at diagnosis, cancer site, and morphology, the number of nodes examined and treatment strategy. Although results were inconsistent for most characteristics, we consistently observed greater age disparities for women with lung cancer compared with men. Also, age disparities increased with more advanced stages for colon cancer and decreased with more advanced stages for lung cancer.

CONCLUSIONS

Although age is one of the most important prognostic factors in cancer survival, age disparities in colon and lung cancer survival have so far been understudied in population-based research. Further studies are needed to better understand age disparities in colon and lung cancer survival.

PROSPERO REGISTRATION NUMBER

CRD42020151402.

The association of comorbidities with administration of adjuvant chemotherapy in stage III colon cancer patients: a systematic review and meta-analysis

Background:

Chemotherapy is an established treatment for stage III colon cancer cases. Older age is known to be associated with less chemotherapy use in these patients, but there might be other relevant factors besides age that influence treatment administration. We summarized evidence on associations between comorbidity and adjuvant chemotherapy administration in stage III colon cancer patients in a systematic review and meta-analysis.

Methods:

We searched the PubMed and Web of Science databases up to 2 June 2020 for studies on comorbidities and chemotherapy use in patients with stage III colon cancer. Summary odds ratios (OR) and 95% confidence intervals (95% CI) were estimated using random-effects models. Subgroup analyses according to year of colon cancer diagnosis, timing of comorbidity assessment, and geographical region were also conducted.

Results:

Thirty-three studies were included in this review, including 219,406 stage III colon cancer patients overall. Chemotherapy administration was 60.9% (95% CI: 56.9% to 64.9%), increasing from 57.1% before 2001 to 66.3% after 2010. There were inverse associations between comorbidities and chemotherapy administration. Compared with patients with Charlson comorbidity score 0, those with scores 1 (OR = 0.79, 95% CI = 0.72–0.87) and 2+ (OR = 0.49, 95% CI = 0.42–0.56) received chemotherapy less often. Among comorbidities, the strongest predictors of chemotherapy non-use were dementia (OR = 0.37, 95% CI = 0.33–0.54), followed by heart failure (OR = 0.44, 95% CI = 0.28–0.70) and stroke (OR = 0.56, 95% CI = 0.38–0.81).

Conclusions:

Merely 60% of stage III colon cancer patients receive chemotherapy. Comorbidities are strong predictors of chemotherapy non-use, but the association differs by comorbid condition and is strongest with dementia. Given the survival disadvantage of colon cancer patients with comorbidities, further evidence on the risk–benefit ratio of chemotherapy according to the type and severity of comorbidity and on the extent to which the survival disadvantage of comorbidity is explained by less use or lower tolerability of chemotherapy is needed to foster personalized medical care in these patients.

Qingjie Fuzheng Granules regulates cancer cell proliferation, apoptosis and tumor angiogenesis in colorectal cancer xenograft mice via Sonic Hedgehog pathway

Background

Sonic Hedgehog (SHh) signaling pathway plays a critical role in cell proliferation, apoptosis, and tumor angiogenesis in various types of malignancies including colorectal cancer (CRC). Qingjie Fuzheng Granules (QFG) is a traditional Chinese medicinal formula, which has been clinically used in various cancer treatments, including CRC. In this study, we explored the potential molecular mechanisms of QFG treatment effects on CRC via the SHh pathway.

Methods

A CRC HCT-116 xenograft mouse model was utilized for all experiments. Mice were treated with intra-gastric administration of 1 g/kg of QFG or saline 6 days a week for 28 days (4 weeks). Body weight, length and shortest diameter of the tumor were measured every 3 days. At the end of the treatment, the tumor weight was measured. TUNEL staining assays were used to detect tumor apoptosis. Western blot and immunohistochemistry (IHC) assays were used to detect the expression of relative proteins.

Results

In our results, QFG inhibited the increase of tumor volume and weight, and exhibited no impact on mouse body weight. Furthermore, QFG significantly decreased the expression of SHh, Smo and Gli proteins, indicating the action of SHh signaling. Consequently, the expression of pro-proliferative survivin, Ki-67, Cyclin-D1 and CDK4 were decreased and expression of anti-proliferative p21 was increased. The pro-apoptotic Bax/Bcl-2 ratio, cle-caspase-3 and TUNEL-positive cell percentage in tumor tissues were increased. Meanwhile, the pro-angiogenic VEGF-A and VEGFR-2 expression was down-regulated.

Conclusions

QFG inhibited CRC cell proliferation and promoted CRC cell apoptosis and tumor angiogenesis in vivo through the suppression of SHh pathway, suggesting that QFG could be a potential therapeutic drug for CRC.

The Older Adults With Rectal Cancer-Does Age Matter?: A Single-center Experience

OBJECTIVES

Oncological treatments of older patients have many unresolved questions mainly because of the fact that these patients were not eligible to be included in most clinical trials. The aim of this study was to evaluate the treatment approach to localized rectal cancer in the older population, including complication rates and overall survival in patients treated with curative intent.

MATERIALS AND METHODS

A retrospective review of patients older than 80 years old (group A) who were treated for clinical stages II to III rectal cancer. The data collection included demographics, comorbidities, treatment protocols, adverse events, time of death, and a comparison with a group of patients aged 65 to 75 years (group B).

RESULTS

A total of 88 patients were included in the analysis (group A, 35; group B, 53). The groups were balanced with regards to sex, comorbidities, pretreatment albumin, and hemoglobin levels (for all categories P>0.05). More patients in group A (25%) received preoperative treatment as in-patients (P=0.022) and were treated with radiation only (P<0.0001) as the initial treatment approach. In group A, in 82% of patients the initial chemotherapy dose was reduced to 75% or less of the calculated dose compared with 7% in group B (P<0.001). Discontinuation of chemotherapy was needed in 55% in group A and 31% in group B (P=0.07). Median overall survival was 33 months in group A and 55 months in group B (P=0.06), 5-year overall survival was 27% and 60%, respectively (P=0.004).

CONCLUSIONS

The age has a significant implication on preoperative treatment, chemotherapy dose, hospitalization rates, and survival.

The influence of socioeconomic position on adjuvant treatment of stage III colon cancer: a systematic review and meta-analysis

BACKGROUND

Patients with colon cancer (CC) with low socioeconomic position (SEP) have a worse survival than patients with high SEP. We investigated the association between different socioeconomic indicators and the steps in the treatment trajectory leading to initiation of adjuvant chemotherapy (ACT) for patients with stage III CC.

MATERIALS AND METHODS

A systematic review and meta-analyses were conducted in accordance with the MOOSE checklist. MEDLINE and EMBASE were searched for eligible studies. Meta-analyses were performed on the separate socioeconomic indicators with the random-effects model. The heterogeneity across studies was assessed by the Q and the I ² statistic.

RESULTS

In total, 27 observational studies were included. SEP was measured by insurance, income, poverty, employment, education, or an index on an area or individual level. SEP, regardless of indicator, was negatively associated with the steps in the treatment trajectory leading to initiation of ACT among patients with resected stage III CC. The meta-analyses showed that patients with low SEP had a significantly lower odds of receiving ACT and increased odds of delayed treatment start, whereas SEP had no impact on the choice of therapy: combination or single-agent therapy.

CONCLUSION

SEP was associated with less initiation of and higher risk for delayed initiation of ACT. Our findings suggest there is a social disparity in receipt of ACT in patients with stage III CC.

Gender differences in stage at diagnosis and preoperative radiotherapy in patients with rectal cancer

Background

Few studies have examined gender differences in the clinical management of rectal cancer. We examine differences in stage at diagnosis and preoperative radiotherapy in rectal cancer patients.

Methods

A prospective cohort study was conducted in 22 hospitals in Spain including 770 patients undergoing surgery for rectal cancer. Study outcomes were disseminated disease at diagnosis and receiving preoperative radiotherapy. Age, comorbidity, referral from a screening program, diagnostic delay, distance from the anal verge, and tumor depth were considered as factors that might explain gender differences in these outcomes.

Results

Women were more likely to be diagnosed with disseminated disease among those referred from screening (odds ratio, confidence interval 95% (OR, CI = 7.2, 0.9–55.8) and among those with a diagnostic delay greater than 3 months (OR, CI = 5.1, 1.2–21.6). Women were less likely to receive preoperative radiotherapy if they were younger than 65 years of age (OR, CI = 0.6, 0.3–1.0) and if their tumors were cT3 or cT4 (OR, CI = 0.5, 0.4–0.7).

Conclusions

The gender-specific sensitivity of rectal cancer screening tests, gender differences in referrals and clinical reasons for not prescribing preoperative radiotherapy in women should be further examined. If these gender differences are not clinically justifiable, their elimination might enhance survival.

Nonadherence to Standard of Care for Locally Advanced Colon Cancer as a Contributory Factor for High Mortality Rates in Kentucky

BACKGROUND

Kentucky has one of the highest mortality rates for colon cancer, despite dramatic improvements in screening. The National Comprehensive Cancer Network (NCCN) guidelines recommend operation and adjuvant chemotherapy for locally advanced (stage IIb/c and stage III) colon cancer (LACC). The purpose of this study was to determine the rate of nonadherence with current standard of care (SOC) and associated factors as possible contributors to mortality.

METHODS

The Kentucky Cancer Registry database linked with administrative health claims was queried for individuals (20 years and older) diagnosed with LACC from 2007 to 2012. Bivariate and logistic regression of nonadherence was performed. Survival analysis was performed with Cox regression and Kaplan-Meier plots.

RESULTS

A total of 1,404 patients with LACC were included. Approximately 42% of patients with LACC were noted to be nonadherent to SOC, with nearly all (95.7%) failing to receive adjuvant chemotherapy. After adjusting for all significant factors, we found the factors associated with nonadherence included the following: age older than 75 years, stage III colon cancer, high Charlson Comorbidity Index (3+), low poverty level, Medicaid coverage, and disability. Adherence to SOC is associated with a significant improvement in the 5-year survival rate compared with nonadherence (63.0% and 27.4%, respectively; p < 0.0001).

CONCLUSIONS

Our study identified multiple factors associated with the failure of patients with LACC to receive SOC, particularly adjuvant chemotherapy, suggesting the need to focus on improving adjuvant chemotherapy compliance in specific populations. Nonadherence to LACC SOC is likely a major contributor to the persistently high mortality rates in Kentucky.