Non-invasive estimation of the circadian rhythm in serum cortisol in patients with ovarian or colorectal cancer

Circadian rhythm disorders in patients with advanced cancer: a scoping review

Circadian rhythms can be demonstrated in several biomarkers and behavioural activities, with rhythmical patterns occurring roughly over a 24-h period. Circadian disorders occur in patients with cancer and may be associated with poor clinical outcomes. This scoping review aimed to identify circadian rhythm research and reporting practices, circadian rhythm patterns, circadian rhythm disorders, and relevant associations of circadian rhythm disorders in patients with advanced cancer. Studies involved adult patients with locally advanced or metastatic cancer and used objective measures of circadian rhythmicity. Two independent authors completed initial screening of title and abstracts, full text reviews, data extraction, and data checking. A total of 98 articles were highlighted in the scoping review, which utilised physical activity measures (actigraphy and polysomnography), biomarkers (cortisol and melatonin), or a combination. Several circadian rhythms are commonly disordered amongst patients with advanced cancer and have significant implications for symptom burden, quality of life, and survival. It remains unclear which patients are most at risk of a circadian rhythm disorder. Significant heterogeneity exists in research and reporting practices. Standardising this approach may address discrepancies in the current literature and allow for research to focus on the most relevant parameters and approaches to improving circadian rhythmicity.

Commonalities in the Features of Cancer and Chronic Fatigue Syndrome (CFS): Evidence for Stress-Induced Phenotype Instability?

Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME) and Cancer-Related Fatigue (CRF) are syndromes with considerable overlap with respect to symptoms. There have been many studies that have compared the two conditions, and some of this research suggests that the etiologies of the conditions are linked in some cases. In this narrative review, CFS/ME and cancer are introduced, along with their known and putative mechanistic connections to multiple stressors including ionizing radiation. Next, we summarize findings from the literature that suggest the involvement of HPA-axis dysfunction, the serotonergic system, cytokines and inflammation, metabolic insufficiency and mitochondrial dysfunction, and genetic changes in CRF and CFS/ME. We further suspect that the manifestation of fatigue in both diseases and its causes could indicate that CRF and CFS/ME lie on a continuum of potential biological effects which occur in response to stress. The response to this stress likely varies depending on predisposing factors such as genetic background. Finally, future research ideas are suggested with a focus on determining if common biomarkers exist in CFS/ME patients and those afflicted with CRF. Both CFS/ME and CRF are relatively heterogenous syndromes, however, it is our hope that this review assists in future research attempting to elucidate the commonalities between CRF and CFS/ME.

Thyroid Cancer and Circadian Clock Disruption

Thyroid cancer (TC) represents the most common malignancy of the endocrine system, with an increased incidence across continents attributable to both improvement of diagnostic procedures and environmental factors. Among the modifiable risk factors, insulin resistance might influence the development of TC. A relationship between circadian clock machinery disfunction and TC has recently been proposed. The circadian clock machinery comprises a set of rhythmically expressed genes responsible for circadian rhythms. Perturbation of this system contributes to the development of pathological states such as cancer. Several clock genes have been found deregulated upon thyroid nodule malignant transformation. The molecular mechanisms linking circadian clock disruption and TC are still unknown but could include insulin resistance. Circadian misalignment occurring during shift work, jet lag, high fat food intake, is associated with increased insulin resistance. This metabolic alteration, in turn, is associated with a well-known risk factor for TC i.e., hyperthyrotropinemia, which could also be induced by sleep disturbances. In this review, we describe the mechanisms controlling the circadian clock function and its involvement in the cell cycle, stemness and cancer. Moreover, we discuss the evidence supporting the link between circadian clockwork disruption and TC development/progression, highlighting its potential implications for TC prevention, diagnosis and therapy.

The effect of therapeutic listening on anxiety and fear among surgical patients: randomized controlled trial

OBJECTIVE

To investigate the effect of therapeutic listening on state anxiety and surgical fears in preoperative colorectal cancer patients.

METHOD

A randomized controlled trial with 50 patients randomly allocated in the intervention group (therapeutic listening) (n = 25) or in the control group (n = 25). The study evaluated the changes in the variables state anxiety, surgical fears and physiological variables (salivary alpha-amylase, salivary cortisol, heart rate, respiratory rate and blood pressure).

RESULTS

In the comparison of the variables in the control and intervention groups in pre- and post-intervention, differences between the two periods for the variables cortisol (p=0.043), heart rate (p=0.034) and surgical fears (p=0.030) were found in the control group, which presented reduction in the values ​​of these variables.

CONCLUSION

There was no reduction in the levels of the variables state anxiety and surgical fears resulting from the therapeutic listening intervention, either through the physiological or psychological indicators. However, the contact with the researcher during data collection, without stimulus to reflect on the situation, may have generated the results of the control group. Clinical Trial Registration: NCT02455128.

The effect of melatonin on sleep and quality of life in patients with advanced breast cancer

BACKGROUND

Fatigue and sleep problems are prevalent in cancer patients and can be associated with disruption of circadian rhythmicity. In this prospective phase II trial, we sought to assess the effect of melatonin on circadian biomarkers, sleep, and quality of life in breast cancer patients.

METHODS

Thirty-two patients with metastatic breast cancer, receiving hormonal or trastuzumab therapy, took 5 mg of melatonin at bedtime for 2 months. Before starting and after 2 months on melatonin therapy, sleep and circadian rhythmicity were assessed by actigraphy, diurnal patterns of serum cortisol, and the expression of the core clock genes PER2 and BMAL1 in peripheral blood mononuclear cells. The European Organisation for Research and Treatment of Cancer (EORTC) QLQ-C30 questionnaire was completed for subjective parameters.

RESULTS

Bedtime melatonin was associated with a significant improvement in a marker of objective sleep quality, sleep fragmentation and quantity, subjective sleep, fatigue severity, global quality of life, and social and cognitive functioning scales. Morning clock gene expression was increased following bedtime melatonin intake. Melatonin did not affect actigraphy measure of circadian rhythmicity, or the diurnal cortisol pattern.

CONCLUSION

These results invite further investigation of melatonin as a potentially useful therapeutic agent for improving sleep and quality of life in cancer patients.

Cancer-related fatigue in the elderly

PURPOSE

Cancer is a disease of the elderly: 60 % of tumours occur in patients aged 65 years or older. Cancer-related fatigue is a common symptom experienced by cancer patients and cancer survivors that profoundly affects all aspects of the quality of life. Although it has been estimated that up to 70 % of elderly with cancer experience fatigue, this symptom is still largely ignored in ageing population.

METHODS

We performed a systematic review of the literature identified by MEDLINE.

RESULTS

The relationship between ageing process and pathogenesis of cancer-related fatigue is still not fully understood.

CONCLUSIONS

Ageing is associated with an increased prevalence of chronic diseases, decreased functional reserve in multiple organ systems and enhanced susceptibility to stress. Ageing and the concomitant presence of a condition of frailty may predispose to the presence of fatigue. Nevertheless, only few studies have to date specifically assessed the impact of fatigue in the geriatric population. Since cancer-related fatigue is a peculiarly debilitating condition characteristic of elderly cancer patient population, we suggest the early recognition and thorough evaluation of the symptom fatigue, its co-existing causes (i.e. anaemia, mood disorders and sleep disturbances) and co-morbidities (i.e., endocrine disorders, metabolic, cardiovascular and liver diseases).

Cancer chronotherapeutics: experimental, theoretical, and clinical aspects

The circadian timing system controls cell cycle, apoptosis, drug bioactivation, and transport and detoxification mechanisms in healthy tissues. As a consequence, the tolerability of cancer chemotherapy varies up to several folds as a function of circadian timing of drug administration in experimental models. Best antitumor efficacy of single-agent or combination chemotherapy usually corresponds to the delivery of anticancer drugs near their respective times of best tolerability. Mathematical models reveal that such coincidence between chronotolerance and chronoefficacy is best explained by differences in the circadian and cell cycle dynamics of host and cancer cells, especially with regard circadian entrainment and cell cycle variability. In the clinic, a large improvement in tolerability was shown in international randomized trials where cancer patients received the same sinusoidal chronotherapy schedule over 24h as compared to constant-rate infusion or wrongly timed chronotherapy. However, sex, genetic background, and lifestyle were found to influence optimal chronotherapy scheduling. These findings support systems biology approaches to cancer chronotherapeutics. They involve the systematic experimental mapping and modeling of chronopharmacology pathways in synchronized cell cultures and their adjustment to mouse models of both sexes and distinct genetic background, as recently shown for irinotecan. Model-based personalized circadian drug delivery aims at jointly improving tolerability and efficacy of anticancer drugs based on the circadian timing system of individual patients, using dedicated circadian biomarker and drug delivery technologies.

Association of worse prognosis with an aberrant diurnal cortisol rhythm in patients with advanced lung cancer

A flatter diurnal rhythm of cortisol has been reported to be associated with early mortality in patients with metastatic breast cancer. The clinical stage of disease at the time of diagnosis and the patient's performance status (PS) are known to be important prognostic factors for lung cancer (LC) survival. The authors examined the relationship between diurnal cortisol rhythms and these prognostic factors in patients with advanced LC. Cortisol concentrations were measured in saliva samples collected from 52 patients (37 males/15 females) with advanced LC and from 56 healthy subjects (32 males/24 females) to characterize the diurnal cortisol rhythm, specifically the cortisol awakening response (CAR) and diurnal cortisol decline (DCD). Variations of CAR and DCD in the patients were analyzed according to their clinical disease stage and PS score, and the differences in CAR and DCD between patients and healthy controls were compared. The patient group showed significantly reduced diurnal cortisol secretory activity and rhythmicity, compared with healthy controls. When the patients were subgrouped according to their clinical disease stage, patients with stage 4 disease showed significantly reduced CAR and flatter DCD compared with the healthy controls. However, the CAR and DCD in patients with stage 3a and 3b disease were comparable to those of healthy controls. Neither the CAR nor the DCD showed stepwise changes as the disease stage worsened. When patients were subgrouped according to their Eastern Cooperative Oncology Group (ECOG) PS score, there was stepwise reduction in the CAR and flattening of the DCD as the PS score increased. Both an abolished CAR and a flattened DCD were common in patients with ECOG PS scores of 3 and 4. These results indicate that alteration of the diurnal cortisol rhythm in patients with advanced LC is more closely associated with their PS score than with their clinical disease stage. Gradual alteration of the CAR and DCD, indicative of loss of 24-h cortisol rhythm, in concert with increase in PS score implies that endogenous circadian rhythms may also be disintegrating as the PS score worsens in these patients.

Alteration of hypothalamic-pituitary-thyroid axis function in non-small-cell lung cancer patients

The aim of this study was to evaluate the hypothalamic-pituitary-thyroid (HPT) axis function in patients suffering from lung cancer. Thyrotropin-releasing hormone (TRH), thyroid-stimulating hormone (TSH), free thyroxine (FT4), interleukin (IL)-2, and melatonin serum levels were measured in blood samples collected every 4 hours for 24 hours from 11 healthy participants (H; ages 35-53 years) and 9 patients suffering from non-small-cell lung cancer (C; ages 43-63 years). Relationships between hormone levels overall and over time of day were evaluated within and among groups. A prominent circadian rhythm with peaks near midnight was present for TSH and melatonin serum levels in both H and C, indicating similar synchronization of the main body clock to the 24-hour environmental light-dark cycle. As regards 24-hour means in H and C, TSH was lower in C, whereas TRH, FT4, and IL-2 were higher in C, with no difference in melatonin levels. Simple linear regression, FT4 versus TRH, showed a positive correlation in H and a negative correlation in C, whereas FT4 versus TSH showed a negative correlation in both groups. For FT4 versus IL-2, a negative correlation was found in C but not for H, whereas TSH versus TRH showed no correlation for either group. Both groups were found to be similarly synchronized to the 24-hour sleep-wake schedule, but HPT axis function was altered in patients suffering from lung cancer. When compared with healthy controls, cancer patients showed modifications of hormone serum levels overall and a negative correlation between individual TRH and FT4 levels.

Diurnal cortisol dysregulation, functional disability, and depression in women with ovarian cancer

BACKGROUND

Multiple alterations in circadian rhythms have been observed in cancer patients, including the diurnal rhythm of the adrenal hormone cortisol. Diurnal cortisol alterations have been associated with cancer-related physiological processes as well as psychological stress. Here we investigate alterations in diurnal cortisol rhythm in ovarian cancer patients, and potential links with depression, life stress, and functional disability.

METHODS

Women (n = 177) with suspected ovarian cancer completed questionnaires and collected salivary cortisol 3× daily for 3 consecutive days before surgery. One hundred women were subsequently diagnosed with ovarian cancer and 77 with benign disease. In addition, healthy women (n = 33) not scheduled for surgery collected salivary cortisol at the same time points.

RESULTS

Ovarian cancer patients demonstrated significantly elevated nocturnal cortisol (P = .022) and diminished cortisol variability (P = .023) compared with women with benign disease and with healthy women (all P values <.0001). Among ovarian cancer patients, higher levels of nocturnal cortisol and less cortisol variability were significantly associated with greater functional disability, fatigue, and vegetative depression, but not with stress, distress, or depressed affect. There were no significant associations between functional or psychological variables and diurnal cortisol in women with benign disease.

CONCLUSIONS

Nocturnal cortisol and cortisol variability show significant dysregulation in ovarian cancer patients, and this dysregulation was associated with greater functional disability, fatigue, and vegetative depression. These findings suggest potential hypothalamic-pituitary-adrenal involvement in functional disability in ovarian cancer, and may have implications for disease progression.

Circadian Disruption, Fatigue, and Anorexia Clustering in Advanced Cancer Patients: Implications for Innovative Therapeutic Approaches

A disruption of the circadian timing system, as identified by monitoring of marker biorhythms, is common in cancer patients. The recording of the rest—activity rhythm with a wrist actigraph has been commonly used. This noninvasive monitoring allows a robust estimation of circadian disruption. The authors have previously found that altered patterns of circadian rest—activity rhythms are significantly and independently associated with the severity of fatigue and anorexia in patients with metastatic colorectal cancer. Elevated proinflammatory cytokines could partly account for this circadian disruption and its associated constitutional symptoms. Here, the authors present and discuss the data supporting the hypothesis that circadian disruption is often associated with fatigue and anorexia, which in turn further alter and dampen circadian synchronization, thus, creating a vicious cycle. This body of evidence paves the path for innovative therapeutic approaches targeting the circadian timing system in an effort to diminish constitutional symptoms induced by cancer and some anticancer treatments.

Cancer-related fatigue

CRF is indisputably a significant problem with important public health and medical economic implications. As the prevalence of cancer survivorship grows, the impact of CRF will increase. Physiatrists have not historically played an active role in caring for affected patients. In the author's opinion, this is unfortunate, since the holistic, integrated, and cross-disciplinary approach that characterizes physiatry seems ideally suited to offer patients meaningful benefit. Physiatrists with a clinical interest are likely to be robustly rewarded with interest from the oncological community, as CRF is a frustrating and devastating problem for patients and clinicians alike.

Pathophysiology of cancer-related fatigue

Cancer-related fatigue (CRF) is influenced and modulated by a number of critical factors, and the mechanism that is both necessary and sufficient to induce development of severe fatigue in patients with cancer has not yet been identified. Specific research efforts to understand the factors that may contribute to CRF development have been made, including studies of the direct effects of tumor burden, the effects of cancer treatment, and other pathophysiologic and psychosocial conditions. Compelling new hypotheses regarding CRF pathophysiology have been proposed, such as the pro-inflammatory hypothesis, the serotonin hypothesis, the vagal-afferent-activation hypothesis, the anemia hypothesis, and the adenosine triphosphate hypothesis; some of these have been tested in both animal models and humans and some in animals only. Gaining an understanding of the specific mechanisms related to the development of fatigue in patients with cancer and survivors requires further investigation. Pathophysiologic research in CRF could be applied in the clinic to improve CRF diagnosis and to enable administration of mechanism-driven interventions. A targeted intervention study with CRF as a primary end point also would be useful.

Mechanisms of cancer-related fatigue

Cancer-related fatigue (CRF) is one of the most prevalent symptoms patients with cancer experience, both during and after treatment. CRF is pervasive and affects patients' quality of life considerably. It is important, therefore, to understand the underlying pathophysiology of CRF in order to develop useful strategies for prevention and treatment. At present, the etiology of CRF is poorly understood and the relative contributions of the neoplastic disease, various forms of cancer therapy, and comorbid conditions (e.g., anemia, cachexia, sleep disorders, depression) remain unclear. In any individual, the etiology of CRF probably involves the dysregulation of several physiological and biochemical systems. Mechanisms proposed as underlying CRF include 5-HT neurotransmitter dysregulation, vagal afferent activation, alterations in muscle and ATP metabolism, hypothalamic-pituitary-adrenal axis dysfunction, circadian rhythm disruption, and cytokine dysregulation. Currently, these hypotheses are largely based on evidence from other conditions in which fatigue is a characteristic, in particular chronic fatigue syndrome and exercise-induced fatigue. The mechanisms that lead to fatigue in these conditions provide a theoretical basis for future research into the complex etiology of this distressing and debilitating symptom. An understanding of relevant mechanisms may offer potential routes for its prevention and treatment in patients with cancer.Disclosure of potential conflicts of interest is found at the end of this article.

Circadian rhythm in dihydropyrimidine dehydrogenase activity and reduced glutathione content in peripheral blood of nasopharyngeal carcinoma patients

Dihydropyrimidine dehydrogenase (DPD) is a rate-limiting enzyme of 5-fluorouracil (5-FU) catabolism. Glutathione (GSH) is a tripeptide involved in platinum complex detoxification. This study explored the circadian rhythms of DPD activity and GSH concentration in the peripheral blood of 16 patients with histologically proven nasopharyngeal carcinoma (NPC) in order to guide the establishment of chronotherapeutic schedules for this cancer. DPD activity and GSH concentration were determined by high performance liquid chromatography (HPLC). Both variables displayed significant circadian rhythms (Cosinor analysis: p = 0.009 and 0.012, respectively). Peak DPD activity occurred at about 02:30 h; whereas, peak GSH concentration occurred around 12:40 h. The differences between the peak and nadir mean values were 25.5% and 38.7%, respectively. The study showed that the circadian rhythms in DPD activity and GSH concentration in Chinese NPC are similar to those reported for western patients with colorectal cancer, despite the differences in race and kinds of cancer. These findings imply that the chronotherapeutic schedule of 5-FU and platinum used to treat European colorectal cancer patients probably is applicable to Chinese NPC patients.

Elevated serum cytokines correlated with altered behavior, serum cortisol rhythm, and dampened 24-hour rest-activity patterns in patients with metastatic colorectal cancer

PURPOSE

Incapacitating symptom burden in cancer patients contributes to poor quality of life (QOL) and can influence treatment outcomes because of poor tolerance to therapy. In this study, the role of circulating cytokines in the production symptoms in cancer patients is evaluated.

EXPERIMENTAL DESIGN

Eighty patients with metastatic colorectal cancer with either normal (group I, n = 40) or dampened (group II, n = 40) 24-hour rest/activity patterns measured by actigraphy were identified. Actigraphy patterns were correlated with QOL indices, serum cortisol obtained at 8:00 a.m. and 4:00 p.m. and with serum levels of transforming growth factor-alpha, tumor necrosis factor-alpha, and interleukin 6 (IL-6) obtained at 8:00 a.m. and analyzed in duplicate by ELISA. Cytokine levels and survival were also correlated.

RESULTS

Group II patients had significantly higher pre treatment levels of all three cytokines, displayed significantly poorer emotional and social functioning, had higher fatigue, more appetite loss, and poorer performance status compared with group I patients. Transforming growth factor-alpha (TGF-alpha) and IL-6 were significantly increased in the patients with WHO performance status >1 and in those with appetite loss. Fatigue was significantly associated with elevated TGF-alpha only. IL-6 was increased in those patients with extensive liver involvement and multiple organ replacement, and it was significantly correlated with dampened cortisol rhythm. In a multivariate analysis, IL-6 was correlated with poor treatment outcome.

CONCLUSIONS

Significant correlations were found between serum levels of TGF-alpha and IL-6, circadian patterns in wrist activity and serum cortisol and tumor-related symptoms in patients with metastatic colorectal cancer. These data support the hypothesis that some cancer patient's symptoms of fatigue, poor QOL, and treatment outcome are related to tumor or host generated cytokines and could reflect cytokine effects on the circadian timing system. This interplay between cytokine signaling pathways, the hypothalamic-pituitary-adrenal axis, the autonomic nervous system, and efferent pathways of the suprachiasmatic nucleus that control circadian physiology, opens the way to new rational interventions for symptom management in cancer patients.

The awakening cortisol response: methodological issues and significance

The awakening cortisol response (ACR) is a discrete and distinctive part of the cortisol circadian cycle. In healthy adults salivary free cortisol concentrations increase by between 50 and 160% in the first 30 min immediately post-awakening (approximate average increase of 9 nmol/l, range 4-15 nmol/l, estimated to be equivalent to about three secretory episodes). However there are no agreed norms for the absolute concentrations of free cortisol in saliva either immediately post-awakening (range of 4.7-18.5 nmol/l) or 30 min post-awakening (range of 8.6-21.9 nmol/l). This review explores reasons for these discrepancies in normative data including confounding factors such as gender, age, awakening time, light and participant adherence. Although the physiological role of the ACR has not been clearly defined evidence is discussed that suggests it is under a distinct regulatory influence, different from the rest of the diurnal cortisol secretory cycle. Despite the difficulties associated with its measurement a range of studies have demonstrated an association between the ACR and psychosocial variables, stress and health. However it remains unclear whether positive affect and good health are consistently associated with larger or smaller awakening responses. It is early days in the search for the role and significance of the ACR. Its putative role in the regulation of physiological function across the day (e.g. the immune system) and its sensitivity to psychosocial variables make it a prime candidate as an intermediary linking mind and health.

Cancer chronotherapy: principles, applications, and perspectives

BACKGROUND

Cell physiology is regulated along the 24-hour timescale by a circadian clock, which is comprised of interconnected molecular loops involving at least nine genes. The cellular clocks are coordinated by the suprachiasmatic nucleus, a hypothalamic pacemaker that also helps the organism adjust to environmental cycles. The rest-activity rhythm is a reliable marker of the circadian system function in both rodents and humans. This circadian organization is responsible for predictable changes in the tolerability and efficacy of anticancer agents, and possibly also may be involved in tumor promotion or growth.

METHODS

Expected least toxic times of chemotherapy were extrapolated from experimental models to human subjects with reference to the rest-activity cycle. The clinical relevance of the chronotherapy principle (i.e., treatment administration as a function of rhythms) has been investigated previously in randomized multicenter trials.

RESULTS

In the current study, chronotherapeutic schedules were used to safely document activity of the combination of oxaliplatin, 5-fluorouracil, and leucovorin against metastatic colorectal carcinoma and to establish new medicosurgical management for this disease, and were reported to result in unprecedented long-term survival.

CONCLUSIONS

Chronotherapy concepts appear to offer further potential to improve current cancer treatment options as well as to optimize the development of new anticancer or supportive agents.

Circadian chronotherapy for human cancers

Cell physiology is regulated by a 24-hour clock, consisting of interconnected molecular loops, involving at least nine genes. The cellular clock is coordinated by the suprachiasmatic nucleus, a hypothalamic pacemaker which also helps the organism to adjust to environmental cycles. This circadian organisation brings about predictable changes in the body's tolerance and tumour responsiveness to anticancer agents, and possibly also for cancer promotion or growth. The clinical relevance of the chronotherapy principle, ie treatment regimens based upon circadian rhythms, has been demonstrated in randomised, multicentre trials. Chronotherapeutic schedules have been used to document the safety and activity of oxaliplatin against metastatic colorectal cancer and have formed the basis for a new approach to the medicosurgical management of this disease, which achieved unprecedented long-term survival. The chronotherapy concept offers further promise for improving current cancer-treatment options, as well as for optimising the development of new anticancer or supportive agents.

Cancer chronotherapy

The cytotoxicity of more than thirty anticancer drugs varies by more than 50% as a function of dosing time along the 24-h time-scale in laboratory animals. Mechanisms involve circadian changes in cellular metabolism and proliferation processes, as well as drug pharmacokinetics. Moreover, the administration of chemotherapy at the least toxic time usually achieves best antitumour efficacy in experimental tumour models. Here we review experiences in utilising these phenomena in the optimization of cancer chemotherapy in the clinic. Chronotherapy has been administered to 1500 patients with metastatic colorectal cancer using 5-fluorouracil and leucovorin with or without oxaliplatin. Sinusoidal chronomodulated delivery of 2- or 3-drug chemotherapy was performed in the patient's home or during usual activities, with a computer-programmed multi-reservoir pump. Courses lasted 4-5 days and were repeated every 14-21 days. Three-drug chronotherapy proved largely superior to flat infusion with respect to both tolerability and antitumour efficacy. The better tolerability of chronotherapy further allowed an increment of both 5-fluorouracil and oxaliplatin doses, which in turn further improved objective tumour response rate to 66%. This enabled surgical removal of previously inoperable metastases and the achievement of > 20% survival at three years. Second generation programmable-in-time pumps have simplified chronotherapy administration and decreased its costs. A broad use of fully ambulatory chronotherapy requires thorough definitions of drug stability, and compatibility with pump reservoirs and other medications.