Neoadjuvant Radiotherapy for Rectal Cancer: Adherence to Evidence-Based Guidelines in Clinical Practice

A process mining approach for clinical guidelines compliance: real-world application in rectal cancer

In the era of evidence-based medicine, several clinical guidelines were developed, supporting cancer management from diagnosis to treatment and aiming to optimize patient care and hospital resources. Nevertheless, individual patient characteristics and organizational factors may lead to deviations from these standard recommendations during clinical practice. In this context, process mining in healthcare constitutes a valid tool to evaluate conformance of real treatment pathways, extracted from hospital data warehouses as event log, to standard clinical guidelines, translated into computer-interpretable formats. In this study we translate the European Society of Medical Oncology guidelines for rectal cancer treatment into a computer-interpretable format using Pseudo-Workflow formalism (PWF), a language already employed in pMineR software library for Process Mining in Healthcare. We investigate the adherence of a real-world cohort of rectal cancer patients treated at Fondazione Policlinico Universitario A. Gemelli IRCCS, data associated with cancer diagnosis and treatment are extracted from hospital databases in 453 patients diagnosed with rectal cancer. PWF enables the easy implementation of guidelines in a computer-interpretable format and visualizations that can improve understandability and interpretability of physicians. Results of the conformance checking analysis on our cohort identify a subgroup of patients receiving a long course treatment that deviates from guidelines due to a moderate increase in radiotherapy dose and an addition of oxaliplatin during chemotherapy treatment. This study demonstrates the importance of PWF to evaluate clinical guidelines adherence and to identify reasons of deviations during a treatment process in a real-world and multidisciplinary setting.

Current status of locally advanced rectal cancer therapy and future prospects

Rectal cancer treatment has been evolving ever since the beginning of the 20th century. Surgery was originally the only available method regardless of the extent of tumor invasion or nodal involvement status. Total mesorectal excision was established as the standard procedure in the early 1990s. Advances in the utilization of radiation for rectal cancer led to the addition of radiotherapy (RT) combined with chemotherapy to the postoperative treatment algorithm. The promising results of the Swedish short-course preoperative RT set the basis for a number of large randomized trials investigating the efficacy of neoadjuvant RT or chemoradiotherapy (CRT) for advanced rectal cancer. Both short-course RT and long-course preoperative CRT compared favorably to adjuvant treatment and became the standard of choice for patients with extramural invasion or lymph node involvement. Recently, the focus of clinical research has been shifted towards total neoadjuvant therapy (TNT), delivering the whole course of RT and chemotherapy before surgery, and showing good tolerance and encouraging efficacy. Although targeted therapies haven't displayed a benefit in the neoadjuvant setting, preliminary evidence suggests impressive efficacy of immunotherapy in rectal carcinomas with mismatch-repair deficiency. In this review, we provide an in-depth critical overview of all significant randomized trials that have shaped the current treatment guidelines for locally advanced rectal cancer and discuss future trends for the treatment of this common malignancy.

Determining the use of preoperative (chemo)radiotherapy in primary rectal cancer according to national and international guidelines

BACKGROUND

Pre-operative radiotherapy (RT) or chemoradiotherapy (CRT) is frequently used prior to rectal cancer surgery to improve local control and survival. The treatment is administered according to guidelines, but these recommendations vary significantly between countries. Based on the stage distribution and risk factors of rectal cancers as determined by magnetic resonance imaging (MRI) in an unselected Swedish population, the use of RT/CRT according to 15 selected guidelines is described.

MATERIALS AND METHODS

Selected guidelines from different countries and regions were applied to a well-characterized unselected population-based material of 686 primary non-metastatic rectal cancers staged by MRI. The fraction of patients assigned to surgery alone or surgery following pre-treatment with (C)RT was determined according to the respective guideline. RT/CRT administered to rectal cancer patients for other reasons, for example, for organ preservation or palliation, was not considered.

RESULTS

The fraction of patients with a clear recommendation for pre-treatment with (C)RT varied between 38% and 77% according to the different guidelines. In most guidelines, CRT was recommended to all patients who were not operated directly, and, in others, short-course RT was also recommended to patients with intermediate risk tumours. If only non-resectable or difficult to resect tumours were recommended pre-treatment, as stated in many Japanese publications, 9% would receive CRT followed by a delay to surgery.

CONCLUSIONS

According to most guidelines, well over 50% of primary non-metastatic rectal cancer patients from a general population, in which screening for colorectal cancer is not practised, are recommended treatment with pre-operative/neo-adjuvant therapy.

A simple matrix to predict treatment success and long-term survival among patients undergoing pancreatectomy

BACKGROUND

A more accurate measure of long-term survival among patients who have undergone a successful resection for pancreatic adenocarcinoma may be computed by accounting for time already survived during the initial treatment window.

METHODS

Patients diagnosed with pancreatic adenocarcinoma, from 2004 through 2013, were identified from the American College of Surgeons National Cancer Database (NCDB). A risk-stratification matrix was constructed including age, histopathologic factors and the use of adjuvant therapy, given successful treatment and survival at 3-month following diagnosis.

RESULTS

A total of 25,897 patients (50% male, 53% >65 years of age) presented with stage I-III pancreatic cancer. The majority of patients had tumors >2 cm size (82%), grade I/II (65%), lymphatic invasion (LI) (66%), and negative margins (76%). A survival advantage for adjuvant therapy was observed among all patients, independent of their risk-profile. For example, a patient ≤65 years of age, with early stage cancer (size ≤2 cm, grade I/II, -ve LI, -ve margins) who received adjuvant therapy had a 62% probability of being alive beyond three years (95%CI = 59%-66%). In contrast, the survival probability decreased to 53% (95%CI = 59%-66%) without adjuvant therapy.

CONCLUSIONS

These results provide surgeons and patients with more accurate information regarding long-term survival, as well as the benefit of opting for adjuvant therapy after successful pancreatic surgery.

Tristetraprolin activation by resveratrol inhibits the proliferation and metastasis of colorectal cancer cells

Resveratrol (RSV) is a polyphenolic compound that naturally occurs in grapes, peanuts and berries. Considerable research has been conducted to determine the benefits of RSV against various human cancer types. Tristetraprolin (TTP) is an AU-rich element-binding protein that regulates mRNA stability and has decreased expression in human cancer. The present study investigated the biological effect of RSV on TTP gene regulation in colon cancer cells. RSV inhibited the proliferation and invasion/metastasis of HCT116 and SNU81 colon cancer cells. Furthermore, RSV induced a dose-dependent increase in TTP expression in HCT116 and SNU81 cells. The microarray experiment revealed that RSV significantly increased TTP expression by downregulating E2F transcription factor 1 (E2F1), a downstream target gene of TTP and regulated genes associated with inflammation, cell proliferation, cell death, angiogenesis and metastasis. Although TTP silencing inhibited TTP mRNA expression, the expression was subsequently restored by RSV. Small interfering RNA-induced TTP inhibition attenuated the effects of RSV on cell growth. In addition, RSV induced the mRNA-decaying activity of TTP and inhibited the relative luciferase activity of baculoviral IAP repeat containing 3 (cIAP2), large tumor suppressor kinase 2 (LATS2), E2F1, and lin‑28 homolog A (Lin28) in HCT116 and SNU81 cells. Therefore, RSV enhanced the inhibitory activity of TTP in HCT116 and SNU81 cells by negatively regulating cIAP2, E2F1, LATS2, and Lin28 expression. In conclusion, RSV suppressed the proliferation and invasion/metastasis of colon cancer cells by activating TTP.

Factors affecting acute myelosuppression induced by radiotherapy and chemotherapy for rectal cancer

AIM

To identify the factors influencing acute myelosuppression induced by radiotherapy and chemotherapy in patients with rectal cancer.

METHODS

From June 2016 to June 2017, 64 rectal cancer patients who underwent synchronous radiotherapy and chemotherapy at our hospital were included. Univariate and Logistic regression analyses were performed to analyze the relationship between pelvic dose parameters and grade 2 acute bone marrow suppression. Three parts of the pelvis, including the lower pelvis, sacrum, and ilium were delineated in the radiotherapy system. Clinical factors analyzed included clinical stage, radiotherapy and chemotherapy, age, gender, and original pigment level. Pelvic dose volume parameters included lower pelvic, sacral, iliac, and pelvic V5, V10, V15, V20, V25, V30, V35, V40, V45, and V50, the average dose (Dmean), and the maximum dose (Dmax).

RESULTS

There were 40 (62.5%) cases of acute myelosuppression in the 64 included patients. Univariate analysis showed that chemotherapy, sex, iliac V20 and V30, and lumbosacral V45 were the main factors associated with acute myelosuppression. Logistic regression analysis showed that iliac V30 and chemotherapy were the main risk factors for acute myelosuppression. Receiver operating characteristic (ROC) analysis showed that the threshold of iliac V30 was 46%.

CONCLUSION

Iliac V30 is an independent risk factor for acute myelosuppression induced by radiotherapy and chemotherapy in patients with rectal cancer. In the treatment of colorectal cancer, the relationship between the local control rate and acute bone marrow suppression should be considered, and iliac V30 should be controlled to < 46% when formulating chemotherapy plan, which can effectively reduce the incidence rate of acute bone marrow suppression.

Association between neoadjuvant chemoradiation and survival for patients with locally advanced rectal cancer

AIM

To examine the overall survival differences for the following neoadjuvant therapy modalities - no therapy, chemotherapy alone, radiation alone and chemoradiation - in a large cohort of patients with locally advanced rectal cancer.

METHOD

Adults with clinical Stage II and III rectal adenocarcinoma were selected from the National Cancer Database and grouped by type of neoadjuvant therapy received: no therapy, chemotherapy only, radiotherapy only or chemoradiation. Multivariable regression methods were used to compare adjusted differences in perioperative outcomes and overall survival.

RESULTS

Among 32 978 patients included, 9714 (29.5%) received no neoadjuvant therapy, 890 (2.7%) chemotherapy only, 1170 (3.5%) radiotherapy only and 21 204 (64.3%) chemoradiation. Compared with no therapy, chemotherapy or radiotherapy alone were not associated with any adjusted differences in surgical margin positivity, permanent colostomy rate or overall survival (all P > 0.05). With adjustment, neoadjuvant chemoradiation vs no therapy was associated with a lower likelihood of surgical margin positivity (OR 0.74, P < 0.001), decreased rate of permanent colostomy (OR 0.77, P < 0.001) and overall survival [hazard ratio (HR) 0.79, P < 0.001]. When compared with chemotherapy or radiotherapy alone, chemoradiation remained associated with improved overall survival (vs chemotherapy alone HR 0.83, P = 0.04; vs radiotherapy alone HR 0.83, P < 0.019).

CONCLUSION

Neoadjuvant chemoradiation, not chemotherapy or radiotherapy alone, is important for sphincter preservation, R0 resection and survival for patients with locally advanced rectal cancer. Despite this finding, one-third of patients in the United States with locally advanced rectal cancer fail to receive stage-appropriate chemoradiation.

Patterns of Rectal Cancer Radiotherapy Adopting Evidence-Based Medicine: An Analysis of the National Database from 2005 to 2016

Purpose

Not many studies have evaluated the adoption and dissemination of evidence-based medicine in rectal cancer radiotherapy (RT). We aimed to analyze the differences by institutional characteristics and geography in adopting evidence-based care for rectal cancer RT and factors affecting the adoption in Korea.

Materials and Methods

Korean National Health Insurance Service claims database was used. All rectal cancer patients treated with radical surgery and adjuvant RT at the same institution in 2005-2016 were included in this study. RT within 3 months before and after surgery was regarded as preoperative and postoperative RT, respectively.

Results

A total of 16,827 patients treated in 83 institutions were included in the analysis. The use of preoperative RT has substantially increased over time, from 40.6% in 2005 to 84.2% in 2016 all over the nation. The proportion of preoperative RT (54.8%) exceeded that of postoperative RT (45.2%) in 2006. However, a wide range of institutional and regional variation was observed. Compared to high-volume institutions, low-volume institutions showed late adoption and variable dissemination patterns of preoperative RT. Busan–Ulsan–Gyeongsangnam-do and Gangwon-do showed slower adoption and less use of preoperative RT than other region.

Conclusion

We demonstrated gradual and steady increase in adoption of preoperative RT in rectal cancer treatment nationally from 2005 to 2016. Institutional variations between high- and low-volume institutions were observed.

Cancer Center Volume and Type Impact Stage-Specific Utilization of Neoadjuvant Therapy in Rectal Cancer

BACKGROUND

Neoadjuvant chemoradiation reduces local recurrence in locally advanced rectal cancer, and adherence to national and societal recommendations remains unknown.

OBJECTIVE

To determine variability in guideline adherence in rectal cancer treatment and investigate whether hospital volume correlated with variability seen.

DESIGN

We performed a retrospective analysis using the National Cancer Database rectal cancer participant user files from 2005 to 2010. Stage-specific predictors of neoadjuvant chemotherapy and radiation use were determined, and variation in use across hospitals analyzed. Hospitals were ranked based on likelihood of preoperative therapy use by stage, and observed-to-expected ratios for neoadjuvant therapy use calculated. Hospital outliers were identified, and their center characteristics compared.

RESULTS

A total of 23,488 patients were identified at 1183 hospitals. There was substantial variability in the use of neoadjuvant chemoradiation across hospitals. Patients managed outside clinical guidelines for both stage 1 and stage 3 disease tended to receive treatment at lower-volume, community cancer centers.

CONCLUSIONS

There is substantial variability in adherence to national guidelines in the use of neoadjuvant chemoradiation for rectal cancer across all stages. Both hospital volume and center type are associated with over-treatment of early-stage tumors and under-treatment of more invasive tumors. These findings identify a clear need for national quality improvement efforts in the treatment of rectal cancer.

Population-based study of effectiveness of neoadjuvant radiotherapy on survival in US rectal cancer patients according to age

Recent cancer researches pay more attention to younger patients due to the variable treatment response among different age groups. Here we investigated the effectiveness of neoadjuvant radiation on the survival of younger and older patients in stage II/III rectal cancer. Data was obtained from Surveillance, Epidemiology, and End Results (SEER) database (n = 12801). Propensity score matching was used to balance baseline covariates according to the status of neoadjuvant radiation. Our results showed that neoadjuvant radiation had better survival benefit (Log-rank P = 3.25e-06) and improved cancer-specific 3-year (87.6%; 95% CI: 86.4–88.7% vs. 84.1%; 95% CI: 82.8–85.3%) and 5-year survival rates (78.1%; 95% CI: 76.2–80.1% vs. 77%; 95% CI: 75.3–78.8%). In older groups (>50), neoadjuvant radiation was associated with survival benefits in stage II (HR: 0.741; 95% CI: 0.599–0.916; P = 5.80e-3) and stage III (HR: 0.656; 95% CI 0.564–0.764; P = 5.26e-08). Interestingly, neoadjuvant radiation did not increase survival rate in younger patients (< = 50) both in stage II (HR: 2.014; 95% CI: 0.9032–4.490; P = 0.087) and stage III (HR: 1.168; 95% CI: 0.829–1.646; P = 0.372). Additionally, neoadjuvant radiation significantly decreased the cancer-specific mortality in older patients, but increased mortality in younger patients. Our results provided new insights on the neoadjuvant radiation in rectal cancer, especially for the younger patients.

Trends with neoadjuvant radiotherapy and clinical staging for those with rectal malignancies

AIM

To see how patterns of care changed over time, and how institution type effected these decisions.

METHODS

A retrospective analysis was performed using the National Cancer Database, looking at all patients that were diagnosed with rectal cancer from 1998 to 2011. We tested differences in rates of treatment and stage migration using χ² tests and logistic regression models.

RESULTS

A review of ninety thousand five hundred and ninety four subjects underwent multimodality therapy for cancer of the rectum. Staging and response to treatment varied greatly between centers. Forty-six percent of the time staging was missing in academic practices, vs fifty-four percent of the time in community centers (P < 0.001). As a result, twenty-percent were down-staged and eight percent up-staged in academia, whereas only fifteen percent were down-staged and 8% up-staged in community practices (P < 0.001). Forty-two percent of individuals underwent radiation before surgery in 1998. Within two years this increased to fifty-three percent. This increased to eighty-six percent by 2011 (P < 0.001). Institution specific treatment varied greatly. Fifty-one percent received therapy before surgery in academic centers in 1998. Thirty-nine percent followed this pattern in the same year in the community (P < 0.001). By 2011, ninety-one percent received radiation before their procedure in academic centers, vs eighty-four percent in the community (P < 0.001). Rates of adoption were better in academia, although an increase was seen in both center types.

CONCLUSION

From the study dates of 1998 to 2011, preoperative treatment with radiation has been on the rise. There is certainly an increased rate of use of radiation in academia, however, this trend is also seen in the community. Practice patterns have evolved over time, although rates of assigning clinical stage are grossly underreported prior to initiation of preoperative therapy.

Enhanced Recovery after Surgery in a Single High-Volume Surgical Oncology Unit: Details Matter

Benefits of ERAS protocol have been well documented; however, it is unclear whether the improvement stems from the protocol or shifts in expectations. Interdisciplinary educational seminars were conducted for all health professionals. However, one test surgeon adopted the protocol. 394 patients undergoing elective abdominal surgery from June 2013 to April 2015 with a median age of 63 years were included. The implementation of ERAS protocol resulted in a decrease in the length of stay (LOS) and mortality, whereas the difference in cost was found to be insignificant. For the test surgeon, ERAS was associated with decreased LOS, cost, and mortality. For the control providers, the LOS, cost, mortality, readmission rates, and complications remained similar both before and after the implementation of ERAS. An ERAS protocol on the single high-volume surgical unit decreased the cost, LOS, and mortality.

Association Between Geographic Access to Cancer Care and Receipt of Radiation Therapy for Rectal Cancer

PURPOSE

Trimodality therapy (chemoradiation and surgery) is the standard of care for stage II/III rectal cancer but nearly one third of patients do not receive radiation therapy (RT). We examined the relationship between the density of radiation oncologists and the travel distance to receipt of RT.

METHODS AND MATERIALS

A retrospective study based on the National Cancer Data Base identified 26,845 patients aged 18 to 80 years with stage II/III rectal cancer diagnosed from 2007 to 2010. Radiation oncologists were identified through the Physician Compare dataset. Generalized estimating equations clustering by hospital service area was used to examine the association between geographic access and receipt of RT, controlling for patient sociodemographic and clinical characteristics.

RESULTS

Of the 26,845 patients, 70% received RT within 180 days of diagnosis or within 90 days of surgery. Compared with a travel distance of <12.5 miles, patients diagnosed at a reporting facility who traveled ≥50 miles had a decreased likelihood of receipt of RT (50-249 miles, adjusted odds ratio 0.75, P<.001; ≥250 miles, adjusted odds ratio 0.46; P=.002), all else being equal. The density level of radiation oncologists was not significantly associated with the receipt of RT. Patients who were female, nonwhite, and aged ≥50 years and had comorbidities were less likely to receive RT (P<.05). Patients who were uninsured but self-paid for their medical services, initially diagnosed elsewhere but treated at a reporting facility, and resided in Midwest had an increased the likelihood of receipt of RT (P<.05).

CONCLUSIONS

An increased travel burden was associated with a decreased likelihood of receiving RT for patients with stage II/III rectal cancer, all else being equal; however, radiation oncologist density was not. Further research of geographic access and establishing transportation assistance programs or lodging services for patients with an unmet need might help decrease geographic barriers and improve the quality of rectal cancer care.

Treatment patterns among colorectal cancer patients in South Australia: a demonstration of the utility of population-based data linkage

RATIONALE, AIMS AND OBJECTIVES

Population level data on colorectal cancer (CRC) management in Australia are lacking. This study assessed broad level patterns of care and concordance with guidelines for CRC management at the population level using linked administrative data from both the private and public health sectors across South Australia. Disparities in CRC treatment were also explored.

METHOD

Linking information from the South Australian Cancer Registry, hospital separations, radiotherapy services and hospital-based cancer registry systems provided data on the socio-demographic, clinical and treatment characteristics for 4641 CRC patients, aged 50-79 years, diagnosed from 2003 to 2008. Factors associated with receiving site/stage-specific treatments (surgery, chemotherapy and radiotherapy) and overall concordance with treatment guidelines were identified using Poisson regression analysis.

RESULTS

About 83% of colon and 56% of rectal cancer patients received recommended treatment. Provision of neo-adjuvant/adjuvant therapies may be less than optimal. Radiotherapy was less likely among older patients (prevalence ratio 0.7, 95% confidence interval 0.5-0.8). Chemotherapy was less likely among older patients (0.7, 0.6-0.8), those with severe or multiple co-morbidities (0.8, 0.7-0.9), and those from rural areas (0.9, 0.8-1.0). Overall discordance with treatment guidelines was more likely among rectal cancer patients (3.0, 2.7-3.3), older patients (1.6, 1.4-1.8), those with multiple co-morbid conditions (1.3, 1.1-1.4), and those living in rural areas (1.2, 1.0-1.3).

CONCLUSIONS

Greater emphasis should be given to ensure CRC patients who may benefit from neo-adjuvant/adjuvant therapies have access to these treatments.

Hospital variation in sphincter preservation for elderly rectal cancer patients

BACKGROUND

The primary goal of an operation for rectal cancer is to cure cancer and, where possible, preserve continence. A wide range of sphincter preservation rates have been reported. This study evaluated hospital variation in the use of low anterior resection (LAR), local excision (LE), and abdominoperineal resection (APR) in the treatment of elderly rectal cancer patients.

METHODS

Using Surveillance, Epidemiology, and End Results-Medicare linked data, we identified 4959 patients older than 65 y with stage I-III rectal cancer diagnosed from 2000-2005 who underwent operative intervention at one of 370 hospitals. We evaluated the distribution of hospital-specific procedure rates and used generalized mixed models with random hospital effects to examine the influence of patient characteristics and hospital on operation type, using APR as a reference.

RESULTS

The median hospital performed APR on 33% of elderly patients with rectal cancer. Hospital was a stronger predictor of LAR receipt than any patient characteristic, explaining 32% of procedure choice, but not a strong predictor of LE, explaining only 3.8%. Receipt of LE was primarily related to tumor size and tumor stage, which combined explained 31% of procedure variation.

CONCLUSIONS

Receipt of LE is primarily determined by patient characteristics. In contrast, the hospital where surgery is performed significantly influences whether a patient undergoes an LAR or APR. Understanding the factors that cause this institutional variation is crucial to ensuring equitable availability of sphincter preservation.

Prognostic factors associated with locally recurrent rectal cancer following primary surgery (Review)

Locally recurrent rectal cancer (LRRC) is defined as an intrapelvic recurrence following a primary rectal cancer resection, with or without distal metastasis. The treatment of LRRC remains a clinical challenge. LRRC has been regarded as an incurable disease state leading to a poor quality of life and a limited survival time. However, curative reoperations have proved beneficial for treating LRRC. A complete resection of recurrent tumors (R0 resection) allows the treatment to be curative rather than palliative, which is a milestone in medicine. In LRRC cases, the difficulty of achieving an R0 resection is associated with the post-operative prognosis and is affected by several clinical factors, including the staging of the local recurrence (LR), accompanying symptoms, patterns of tumors and combined therapy. The risk factors following primary surgery that lead to an increased rate of LR are summarized in this study, including the surgical, pathological and therapeutic factors.

Patterns of Pelvic Radiotherapy in Patients with Stage II/III Rectal Cancer

High-level evidence supports adjuvant radiotherapy for rectal cancer. We examined the influence of sociodemographic factors on patterns of adjuvant radiotherapy for resected Stage II/III rectal cancer. Methods. Patients undergoing surgical resection for stage II/III rectal cancer were identified in SEER registry. Results. A total of 21,683 patients were identified. Majority of patients were male (58.8%), white (83%), and with stage III (54.9%) and received radiotherapy (66%). On univariate analysis, male gender, stage III, younger age, year of diagnosis, and higher socioeconomic status (SES) were associated with radiotherapy. Radiotherapy was delivered in 84.4% of patients <50; however, only 32.8% of those are >80 years. Logistic regression demonstrated a significant increase in the use of radiotherapy in younger patients who are <50 (OR, 10.3), with stage III (OR, 1.21), males (OR, 1.18), and with higher SES. Conclusions. There is a failure to conform to standard adjuvant radiotherapy in one-third of patients, and this is associated with older age, stage II, area-level of socioeconomic deprivation, and female sex.