Oncology & Supportive Care
Cachexie cancéreuse | Clinique Omicron Québec
Cancer cachexia is a complex, multifactorial metabolic syndrome, irreversible in its advanced stages, defined by progressive loss of skeletal muscle mass - with or without loss of fat mass - which cannot be fully corrected by conventional nutritional intake, and which leads to progressive functional deterioration. According to the international consensus published in The Lancet Oncology in 2011 (Fearon et al.), the diagnostic criteria are: weight loss greater than 5 % in 6 months, or weight loss greater than 2 % associated with a body mass index of less than 20 kg/m² or documented sarcopenia. Cancer cachexia is distinct from simple intake-deficiency undernutrition - indeed, even when nutritional intakes are optimally increased, muscle mass loss continues due to profound metabolic disturbances induced by tumor and systemic pro-inflammatory cytokines. It affects 50 to 80 % of cancer patients, depending on tumor type - up to 80 % of pancreatic and gastric cancers - and is directly responsible for 20 to 30 % of cancer deaths (not from the cancer itself, but from its consequences - respiratory muscle failure, immunodepression, sepsis, treatment intolerance). It reduces quality of life, tolerance to chemotherapy, response to treatment and overall survival - irrespective of tumor stage. Despite its major prognostic importance, cancer cachexia remains under-diagnosed and under-treated in routine clinical practice, not least because it is often wrongly perceived as an inevitable and irreversible consequence of advanced cancer.
Pathophysiology
- Chronic systemic inflammation - the central driver of cachexia: tumor cells and host immune cells produce excess pro-inflammatory cytokines - mainly TNF-α (tumor necrosis factor alpha - formerly known as cachectin), IL-1β, IL-6 and interferon-γ ; these cytokines directly activate muscle proteolysis via the ubiquitin-proteasome system (main pathway for muscle protein degradation) and the caspase pathway (myocyte apoptosis); IL-6 stimulates hepatic synthesis of acute-phase proteins (CRP, fibrinogen, haptoglobin) at the expense of albumin, transthyretin and prealbumin - explaining the hypoalbuminemia of cachexia
- Proteolysis-inducing factor (PIF) and lipid-mobilizing factor (LMF): soluble tumor-derived factors (described in pancreatic cancers) - PIF directly activates muscle ubiquitin proteasome independently of systemic cytokines; LMF activates adipocyte lipolysis via hormone-sensitive lipase → release of free fatty acids → hepatic oxidation → ketone bodies; explains early loss of fat mass in some cancers even before muscle loss
- Anorexia and metabolic alterations: cytokines - in particular IL-1β and TNF-α - cross the blood-brain barrier and activate hypothalamic satiety centers (arcuate nucleus - melanocortin pathway) → central anorexia; melanokortins (α-MSH) activated → appetite inhibition ; neuropeptide Y (NPY) and endogenous ghrelin - orexigenic systems normally stimulated by fasting - respond attenuated in cancer cachexia (central resistance to ghrelin); taste and smell altered by chemo and radiotherapy → reinforcement of anorexia
- Insulin resistance and hyperglycemia: cancer cachexia is systematically accompanied by peripheral (muscle and liver) insulin resistance - mediated by TNF-α and IL-6 ; chronic hyperglycemia fuels tumor gluconeogenesis (Warburg effect - tumor cells preferentially consume glucose in anaerobic glycolysis, even in the presence of oxygen) and hepatic gluconeogenesis from muscle amino acids (substrate for gluconeogenesis) → vicious circle of muscle catabolism
- Increased resting energy expenditure (REE): paradoxically, cachexia is accompanied by an increase in DER of 10 to 30 % compared with expected values depending on weight - linked to thermogenesis of brown adipocytes (browning of white adipose tissue - browning) activated by PIF and cytokines, and futile cycling (futile ATP cycles between protein synthesis and degradation and between glycolysis and gluconeogenesis) - energy expenditure increases even as intakes decrease → accelerated cumulative energy deficit
Stages of cancer cachexia (Fearon 2011 consensus)
| Stadium | Criteria and features | Therapeutic goal |
|---|---|---|
| Pre-cachexia | Weight loss ≤ 5 %; anorexia and early metabolic abnormalities (slightly elevated CRP, mild insulin resistance, hypertriglyceridemia); no significant muscle loss yet; cancer often controllable at this stage | Prevention - intervene early |
| Cachexia | Weight loss > 5 % in 6 months, OR loss > 2 % with BMI < 20 kg/m² or sarcopenia; anorexia, fatigue, reduced muscle strength; systemic inflammation (elevated CRP, hypoalbuminemia); anti-tumor treatment often ongoing. | Stabilization - limiting progression |
| Refractory cachexia | Rapidly progressive, treatment-resistant cancer; weight loss > 10-15 %; survival prognosis < 3 months; performance status WHO 3-4; no response to nutritional interventions; symptomatic treatment and comfort measures only. | Comfort - quality of life |
Cancers at high risk of cachexia
| Type of cancer | Prevalence of cachexia | Specific mechanisms |
|---|---|---|
| Pancreatic cancer | 80-85 % | tumoral PIF and LMF, exocrine pancreatic insufficiency (malabsorption of fats and proteins), biliary obstruction, intense abdominal pain limiting feeding, nausea |
| Stomach cancer | 70-80 % | Gastric mechanical obstruction, achlorhydria, vomiting, gastrectomy (post-surgical malabsorption) |
| Esophageal cancer | 70-75 % | Progressive dysphagia → severe dietary restriction; extensive surgery; locoregional radiotherapy → mucositis, esophagitis, fistulae |
| Colorectal cancer | 50-60 % | Intestinal obstruction, malabsorption, diarrhea (secretory tumors, exudative enteropathy), repeated surgery (stomas) |
| Lung cancer | 45-60 % | Intense systemic inflammation, toxic chemotherapy (nausea, mucositis), dyspnea limiting physical activity and appetite |
| Head and neck cancer | 40-50 % | Dysphagia, odynophagia, xerostomia and mucositis post-radiotherapy, major taste alterations, trismus |
| Leukemia and lymphoma | 30-50 % | Massive pro-inflammatory cytokines, complications of intensive chemotherapy (mucositis, diarrhea, febrile neutropenia), stem cell transplantation |
| Breast and gynecological cancers | 15-40 % | Less frequent; hormone therapy and chemotherapy sometimes induce paradoxical weight gain; cachexia more frequent in metastatic stages |
ℹ️
Cancer cachexia is not a simple «anorexia» that can be corrected by «eating more» - unlike undernutrition due to lack of intake. Even with perfectly optimized caloric and protein intake, muscle loss continues due to profound metabolic disturbances (ubiquitin-proteasome proteolysis, insulin resistance, hypercatabolism). This is why nutritional support alone is not enough: a multimodal approach combining nutrition, adapted physical activity and drugs targeting inflammation is required.
Diagnosis and assessment
- Diagnostic criteria (international consensus 2011): weight loss > 5 % over 6 months (without voluntary dieting) OR weight loss > 2 % with BMI 2 % with sarcopenia documented by muscle mass measurement (L3 scan, DEXA or bioimpedancemetry).
- Assessment of anorexia and symptoms: FAACT (Functional Assessment of Anorexia/Cachexia Treatment) scale - validated score including appetite, gastrointestinal symptoms and cachexia-related quality of life; CACS (Cancer Appetite and Symptom Questionnaire) appetite scale; ESAS (Edmonton Symptom Assessment System) score - global assessment of symptoms in palliative oncology
- Biological work-up: serum albumin (marker of nutritional status and inflammation - normal 35-50 g/L; cachexia : often < 30 g/L); prealbumin/transthyretin (half-life 2-3 days - marker more sensitive to acute variations in nutritional status than albumin); CRP (marker of systemic inflammation - correlated with severity of cachexia and prognosis) ; CRP/albumin ratio (modified Glasgow ratio - a prognostic score validated in oncology); CBC (anaemia - frequent and aggravating fatigue and anorexia); ionogram, urea, creatinine; blood glucose (insulin resistance); thyroid work-up (exclude aggravating hypothyroidism); ferritin, vitamin D, zinc (frequently associated deficiencies).
- Assessment of body composition: abdomino-pelvic CT scan at L3 level (analysis of the muscle surface of the psoas and paravertebral muscles on axial section) - reference method for sarcopenia in oncology; DEXA (biphotonic X-ray absorptiometry) - measures lean mass and total fat mass; bioimpedancemetry (BIA) - accessible, non-irradiating, good correlation with DEXA for longitudinal follow-up
- Performance status and muscle strength: WHO/ECOG performance status (0-4); grip strength (handgrip strength) - a simple, reproducible functional marker correlated with survival and treatment tolerance; 6-minute walk test; Timed Up and Go (TUG) test.
Multimodal treatment
- Nutritional support - an essential first step: caloric targets 25-35 kcal/kg/day (depending on measured energy expenditure) and protein targets 1.2-1.5 g protein/kg/day (higher than the needs of a healthy subject due to increased catabolism); individualized dietary counseling by a nutritionist/dietitian - meal enrichment (oil, butter, milk powder) rather than increasing volume; meal splitting (6-8 small meals/day); high-protein, high-calorie oral nutritional supplements (1.5-2 kcal/mL - Ensure, Boost, Fortisip); omega-3 fatty acids (EPA - eicosapentaenoic acid): 2 g/day - reduction in pro-inflammatory cytokines, attenuation of muscle proteolysis; meta-analyses (Cochrane 2021) showing moderate improvement in weight and appetite ; enteral nutrition (nasogastric tube or percutaneous gastrostomy for head and neck and esophageal cancers) if oral route insufficient ( 3 months
- Adapted physical activity (APA) - only proven intervention to counter muscle loss: resistance exercise (adapted weight training) - stimulates muscle protein synthesis via IGF-1/mTOR pathway, antagonizes cytokine-induced proteolysis; minimum target: 150 minutes of moderate activity per week according to ASCO 2019; APA program supervised by a kinesiologist or physiotherapist specialized in oncology; HIIT (high-intensity interval training) adapted to the patient - benefits on muscle mass, fatigue, quality of life and treatment tolerance; to be initiated as early as the pre-cachexia stage
- Pharmacological treatments for anorexia: megestrol acetate (Megace) 160-800 mg/day - synthetic progestin; increases appetite and weight (especially body fat); improves subjective well-being; side effects: deep vein thrombosis (risk ×2-3), edema, adrenal insufficiency on abrupt discontinuation, diabetes, hypertension; not recommended in curative phase due to high thromboembolic risk; corticosteroids (dexamethasone 4 mg/day or prednisone 20-40 mg/day) - rapid improvement in appetite and well-being over 2-4 weeks ; unsustained efficacy beyond 4 weeks; reserved for advanced palliative stages or in combination with chemotherapy to reduce nausea; dronabinol (synthetic THC) and nabilone (cannabinoid) - modest appetite stimulants, psychotropic side-effects limit practical use (not reimbursed for this indication in Quebec in most regimens)
- Agents targeting muscle metabolism (emerging): anamorelin (selective ghrelin receptor agonist) - ROMANA 1 and 2 trials (2015): significant increase in lean body mass and appetite in patients with non-small cell lung cancer; approved in Europe and Japan for cancer cachexia in lung cancer; not yet approved by Health Canada or the FDA; enobosarm (ostarine - SARM - selective androgen receptor modulator) - ongoing trials in oncology; formoterol and other β2-agonists - inhibit muscle proteolysis via the cAMP/PKA pathway; thalidomide - TNF-α inhibitor, weight improvement in phase II pancreatic cancer; therapeutic hope but not yet in standard practice
- Management of contributing symptoms: nausea and vomiting - metoclopramide, ondansetron, dexamethasone (pre-chemotherapy); pain - optimization of analgesia (WHO level) as chronic pain contributes to anorexia and catabolism; constipation (frequent under opioids) - preventive laxatives ; post-radiotherapy mucositis - mouthwash, local analgesia, early dental care; xerostomia - oral hygiene, salivary substitutes, pilocarpine; gastroparesis - metoclopramide, domperidone; depression and anxiety (frequent in cachexia, self-maintenance of the anorexia-cachexia syndrome) - integrated psychological and psychiatric care.
- Palliative care and refractory cachexia: at this stage, force-feeding and artificial nutrition do not prolong survival and may worsen comfort; expert consensus recommends an approach focused on quality of life, comfort and communication with the patient and family; discuss realistic expectations regarding nutrition; parenteral nutrition in the terminal phase is not routinely recommended (unproven benefit, risk of complications); supportive care includes symptom management (nausea, pain, anxiety), psychological support and maintenance of eating pleasure whenever possible
When to seek help quickly
Consult a physician or healthcare professional on the oncology team without delay if you experience rapid weight loss (> 5 % in less than 3 months), severe and increasing fatigue, inability to eat, uncontrolled vomiting or nausea, marked muscle weakness (difficulty getting up from a chair, climbing stairs) or significant impairment of day-to-day functional abilities. These signs may indicate a progression of cachexia towards a refractory stage, and require rapid oncological, nutritional and palliative care reassessment to adjust management and preserve quality of life. Clinique Omicron's physicians and professionals can coordinate this assessment and refer patients to the specialized resources available in Quebec.
Consult at Clinique Omicron
Clinique Omicron supports cancer patients in their overall care, complementing the oncology team: nutritional assessment, prescription of nutritional supplements, referral to oncology-specialized dietitians and kinesiologists, management of contributing symptoms (nausea, pain, depression) and coordination with palliative care teams. Consultations are available at our points of service in Quebec, as well as via telemedicine across the province. To book an appointment, visit cliniqueomicron.ca.
The content of this page is provided for information purposes only and does not replace the advice of a qualified healthcare professional. The management of cancer cachexia is a multidisciplinary approach requiring the involvement of the oncology, nutrition and palliative care teams.
Omicron Clinic
Need to consult a doctor?
Treatment within 24-48 hours. In-clinic or telemedicine, anywhere in Quebec.
Insurance receipts. 7j/7. No family doctor required.