Can we predict toxicity and efficacy in older patients with cancer? Older patients with colorectal cancer as an example

Time trends in treatment patterns and survival of older patients with synchronous metastatic colorectal cancer in the Netherlands: A population-based study

New treatment strategies have improved survival of metastatic colorectal cancer in trials. However, it is not clear whether older patients benefit from these novel therapies, as they are often not included in pivotal trials. Therefore, we investigated treatment patterns and overall survival over time in older patients with metastatic colorectal cancer in a population-based study. We identified 22.192 Dutch patients aged ≥70 years diagnosed with synchronous metastatic colorectal cancer between 2005 and 2020 from the Netherlands Cancer Registry. Changes in treatment over time were assessed with logistic regression models. Survival was assessed by Cox proportional hazard ratios (HR). Results showed that chemotherapy use increased between 2005 and 2015, but declined from 2015 onwards, while more patients received best supportive care. Over time, fewer patients underwent primary tumor resection alone. Although survival of both metastatic colon and rectal cancer improved until 2014, survival of colon cancer decreased from 2014 onwards (HR 1.04, 95% confidence interval [CI] 1.01-1.05), which was seen in all age groups. Survival of metastatic rectal cancer patients remained unchanged from 2014 onwards (HR 1.00, 95% CI 0.98-1.03) in all age groups. In conclusion, treatment patterns of Dutch older patients with synchronous metastatic colorectal cancer rapidly changed from 2005 to 2020, with increasing percentages of patients receiving best supportive care. Survival of metastatic colon cancer decreased from 2014 onwards. The implementation of a colorectal cancer screening program and patient selection might explain why only a subset of older patients seem to benefit from the availability of novel treatment options.

Systematic Review of Treatments for Colorectal Metastases in Elderly Patients to Guide Surveillance Cessation Following Hepatic Resection for Colorectal Liver Metastases

BACKGROUND

Although included in surveillance programmes for colorectal cancer (CRC) metastases, elderly patients are susceptible to declines in health and quality of life that may render them unsuitable for further surveillance. Deciding when to cease surveillance is challenging.

METHODS

There are no publications focused on surveillance of elderly patients for CRC metastases. A systematic review of studies reporting treatment outcomes for CRC metastases in elderly patients was performed to assess the risk-benefit balance of the key objectives of surveillance; detecting and treating CRC metastases.

RESULTS

Sixty-eight eligible studies reported outcomes for surgery and chemotherapy in the elderly. Liver resections and use of chemotherapy, including biologics, are more conservative and have poorer outcomes in the elderly compared with younger patients. Selected studies demonstrated poorer quality-of-life (QoL) following surgery and chemotherapy. Studies of ablation in elderly patients are limited.

DISCUSSION

The survival benefit of treating CRC metastases with surgery or chemotherapy decreases with advancing age and QoL may decline in the elderly. The relatively lower efficacy and detrimental QoL impact of multimodal therapy options for detected CRC metastases in the elderly questions the benefit of surveillance in some elderly patients. Care of elderly patients should thus be customized based on their preference, formal geriatric assessment, natural life-expectancy, and the perceived risk-benefit balance of treating recurrent CRC metastases. Clinicians may consider surveillance cessation in patients aged 75 years and above if geriatric assessment is unsatisfactory, patients decline surveillance, or patient fitness deteriorates catastrophically.

A simulation study of approaches for handling disease progression in dose-finding clinical trials

In traditional dose-finding studies, dose-limiting toxicity (DLT) is determined within a fixed time observation window where DLT is often defined as a binary outcome. In the setting of oncology dose-finding trials, often patients in advanced stage of diseases are enrolled. Therefore, disease progression may occur within the DLT observation window leading to treatment discontinuation and rendering the patient unevaluable for DLT assessment. As a result, additional patients have to be enrolled, increasing the sample size. We propose and compare several practical approaches for handling disease progression which occurs within the DLT observation window, while in the framework of the time-to-event continual reassessment method (TITE-CRM) which allows using partial observations. The approaches differ on the way they define an evaluable patient and in the way incomplete observations are included. The practical approaches, which we call strategies A, B and C, are illustrated and contrasted in the context of a single simulated trial, and compared via simulations under various scenarios of dose-progression relationship, in the setting of advanced soft-tissue sarcoma.

Personalised treatment for older adults with cancer: The role of frailty assessment

It is widely accepted in clinical practice that chronological age is a poor predictor of treatment tolerance and outcomes in older adults with cancer. Intrinsic vulnerability is more a function of underlying frailty, rather than chronological age. Frailty is a state of increased vulnerability to stressors, such as cancer and its treatment, which can lead to adverse health outcomes for patients. Capturing this heterogeneity in reserve capacity is the cornerstone of management in geriatricmedicine, but remains poorly understood or adopted in radiation oncology. A two-step approach, using a shorter screening tool, followed by full assessment for those who need it, is the mostresourceful way of implementing frailty assessment in radiotherapy departments. It is important for radiation oncology professionals to identify frailty and to use this information in multidisciplinary decision making in order to develop a personalised radiotherapy approach for the older person. There are many ways we can effectively use this information, such as considering treatment fractionation schedules that would limit the burden of travel for those with social frailty, or reviewing the range of modalities at our disposal, which might limit toxicity in the older person at high risk of deterioration during treatment. Frailty assessment is not carried out in many radiotherapy departments presently, but there are many international models to use as exemplars as to how it may be implemented in clinical practice. There are many opportunities for further research and role development in this field at the current time.

First-line trifluridine/tipiracil plus bevacizumab for unresectable metastatic colorectal cancer: SOLSTICE study design

Trifluridine/tipiracil (TT) is an orally administered combination of the thymidine-based nucleoside analogue trifluridine and the thymidine phosphorylase inhibitor tipiracil hydrochloride, which increases the bioavailability of cytotoxic trifluridine. Encouraging antitumor activity of first-line TT + bevacizumab (TT-B) has been observed in a Phase II study in patients with unresectable metastatic colorectal cancer ineligible for combination oxaliplatin- or irinotecan-based therapy. Here, we describe the design of SOLSTICE (NCT03869892), an open-label, Phase III trial in unresectable metastatic colorectal cancer patients who are not candidates for, or do not require, intensive therapy. The 854 patients were randomized 1:1 to receive first-line TT-B versus capecitabine + bevacizumab. The primary objective is to demonstrate superior progression-free survival with TT-B over capecitabine + bevacizumab. The first patient was enrolled in March 2019.

Treatment outcomes in older patients with advanced gastrointestinal stromal tumor (GIST)

BACKGROUND

The aim of the study was to analyze the treatment results of advanced GIST in the largest, homogenous series of older patients.

METHODS

Between 2001 and 2016, 686 patients with metastatic/unresectable GIST were treated initially with imatinib and 656 were included in the analysis. Subsequently 232 patients were treated with sunitinib after imatinib failure. We have analyzed the outcomes of patients who have been treated with the tyrosine kinase inhibitor at the age ≥ 70 years and compared to control group of patients younger than 70 years old.

RESULTS

In the group of patients treated with imatinib, 139 (21%) started therapy at the age of at least 70 years (median age of the entire cohort: 60). Median progression-free survival (PFS) on 1st line imatinib did not differ between patients ≥70 yo (years old) and < 70yo (38.5 vs 44.9 months), but median overall survival (OS) was significantly better for younger patients (81 months vs. 50; p = 0.0001; although disease-specific survival - DSS was similar). Distribution of primary tumor mutational status was generally similar in older and younger patients. Permanent dose reduction (300-100 mg/day) was required for 23 patients (16.9%) in the older group and was significantly more frequent as compared to younger patients (5%). Drug-related adverse events were mainly of grades 1/2, but grade 3/4 toxicity occurred more frequently in older (14.7%) than in younger patients (3.8%). Similarly in group of patients treated with second-line sunitinib median PFS and DSS were comparable in groups of patients ≥70 yo (n = 55) and < 70yo (9.7 months vs 10.3 months; p = 0.7, and 21.5 vs 22.9 months). >40% of patients in both groups required dose adjustments to 37.5-25 mg daily.

CONCLUSIONS

Our study confirms that current therapy of advanced GIST with tyrosine kinase inhibitors (both in 1st and 2nd line) in older patients enable to achieve the similar disease control rate and final outcomes as in younger patients, but it demands close cooperation of experienced oncologist with patients for dose modifications and side effects management. Limitation of our study is that the patients did not undergo a comprehensive geriatric assessment, what might be helpful for personalized management of patients. Nevertheless, we confirm that older patients with GIST should not receive less treatment irrespective of comorbidities.

Inclusion of elderly or frail patients in randomized controlled trials of targeted therapies for the treatment of metastatic colorectal cancer: A systematic review

Treatment of metastatic colorectal cancer (mCRC) has been modified since the launching of targeted therapies. Colorectal cancer (CRC) is common in elderly patients; their representation in randomized controlled trials (RCTs) is thus crucial. This study aimed to evaluate and quantify the inclusion of elderly/frail patients in RCTs of targeted therapies in mCRC. A systematic review using Medline, Scopus, Cochrane Database and ISI Web of Science was performed to identify all phase II/III RCTs of bevacizumab, cetuximab, panitumumab, regorafenib and aflibercept in mCRC until January 2015. Two reviewers independently performed studies selection, and data extraction. The protocol was registered in Prospero (CRD42015016163). Among 1,369, identified publications, 54 RCTs were selected. Nine RCTs (17%) excluded elderly patients; median age of the included population was <65years old in 50 RCTs (93%). Twenty RCTs (37%) excluded frail patients, and many RCTs excluded patients with uncontrolled hypertension or heart failure, patients treated with specific drugs (mainly anticoagulants), and patients with inadequate creatinine clearance. Elderly/frail patients are underrepresented in RCTs studying targeted therapies in mCRC, and those elderly patients included in RCTs do not reflect well the general elderly population with mCRC because of the exclusion criteria. RCTs results concerning targeted therapies can be inferred only to relatively healthy elderly subjects.

Randomized study comparing full dose monotherapy (S-1 followed by irinotecan) and reduced dose combination therapy (S-1/oxaliplatin followed by S-1/irinotecan) as initial therapy for older patients with metastatic colorectal cancer: NORDIC 9

Background

Metastatic colorectal cancer (mCRC) is a disease of older age, but there is a relative lack of knowledge about effects of chemotherapy in older patients as they are under-represented in clinical trials. Little data can guide whether the strategy in older mCRC patients should be a sequential full-dose monotherapy chemotherapy approach or a dose-reduced combination chemotherapy approach. The oral 5FU prodrug S-1 seems to have less side effects than capecitabine and should be an optimal drug for older patients, but few data are available. Improved geriatric assessments are needed to select which older patients should receive therapy.

Methods

The NORDIC 9 trial is a Nordic multicenter randomized phase II study comparing full dose monotherapy (S-1 30 mg/m² twice daily days 1–14 every 3 weeks, followed by second line irinotecan 250–350 mg/m² iv day 1 every 3 weeks or 180–250 mg/m² iv day 1 every 2 weeks) with reduced dose combination therapy (S-1 20 mg/m² days 1–14 + oxaliplatin 100 mg/m² iv day 1 every 3 weeks, followed by second line S-1 20 mg/m² days 1–14 + irinotecan 180 mg/m² day 1 every 3 week) for older patients (≥70 years) with mCRC who are not candidates for full-dose standard combination therapy. Additional bevacizumab (7.5 mg/kg) is optional in first-line. Blood samples and tumor tissue will be collected to investigate predictive markers. Geriatric screening tools (G-8, VES-13, Timed-Up-and-Go and Handgrip strength), Charlson Comorbidty Index and quality of life (EORTC QLQ-C30) will be evaluated as predictors of efficacy and toxicity. The target sample size is 150 patients.

The primary endpoint is progression-free survival and secondary endpoints are time-to-failure of strategy, overall survival, response rate, toxicity, and correlations between biomarkers, pre-treatment characteristics and geriatric assessments.

Discussion

The study will add knowledge on how to treat older mCRC patients who are not candidates for standard combination therapy. Furthermore it may provide understanding of efficacy and tolerability of chemotherapy in older cancer patients and thus offer a better chance for tailored treatment strategies in these patients.

Trial registration

EU Clinical Trial Register, EudraCT no. 2014–000394-39. Registered 05 May 2014.