PN in advanced cancer

Question 1

Definitions of malnutrition, sarcopenia, cachexia

Answer 1

• malnutrition: imbalance in protein-energy due to starvation
• sarcopenia: the loss of muscle mass & strength
• cachexia: disease-associated malnutrition causing metabolic changes, reduced food intake and resulting in muscle loss (with or without fat mass)

Question 2

The 3 stages of cancer cachexia

Answer 2

• Precachexia: weight loss of <5% with anorexia and metabolic changes
• Cachexia: weight loss of >5% or 2% with BMI <20 or sarcopenia diagnosis. Reduction in food intake and systemic inflammation
• Refractory cachexia: associated with proximity to death (<3 months left to live). Cachexia is procatabolic and non-responsive to treatment with a low performance score

Question 3

The multifactorial process of cancer cachexia (including systemic inflammatory syndrome)

Answer 3

• metabolic dysfunction, catabolic tumour factors
• systemic inflammatory syndrome: increase in acute phase proteins, increased fat and protein oxidation, impaired glucose tolerance and insulin resistance
• anorexia due to dysgeusia (bad taste in the mouth), altered gut motility (leading to early satiety), food aversion, emotional adjustment, decreased physical activity

Question 4

Nutritional screening in cancer cachexia

Answer 4

• Needs to be done upon admission and weekly thereafter
• issue is that cancer treatment may cause weight loss and malnutrition independent of cachexia
• use anthropometry, CT/MRI to monitor

Question 5

Definition and aims of multimodal nutrition approaches for cancer cachexia

Answer 5

• Definition: exercise, omega 3, pharmacological anabolic agents (corticosteroids)
• Aims: reduce treatment interruption, treating cachexia, improving/maintaining QoL

Question 6

Enteral nutritional support and ‘conditioning’

Answer 6

• enteral feeds can be given by NG, NJ or gastronomy tubes
• need to plan enteral feeds i.e. for head and neck cancer place a gastonomy early
• conditioning: after treatment of cancer usually a wait of 4 weeks before surgery, this wait should be used for nutritional support. Peri-operative patients unlikely to eat in 5 days or <50% intake in 7 days should be given artificial nutrition

Question 7

When is PN/HPN indicated?

Answer 7

• upon intestinal failure: mechanical obstruction, fistulae, SBS, intestinal dysmotility, extensive small bowel mucosal disease
• cancer treatment efficacy is becoming affected by the extent of malnutrition
• HPN is considered when survival is >2 months, EN not sufficient to meet requirements, PN expected to stabilise performance/QoL, patient desires PN

Question 8

Definitions of intestinal failure: acute/chronic, 3 types, 5 pathophysiologies

Answer 8

• definition: the reduction in functioning gut mass below the minimum amount necessary for adequate absorption of energy, macronutrients and/or H2O and electrolytes, such that IV supplementation is needed
• acute: ileus/enteritis due to obstruction, chemo, infection
• chronic: short bowel syndrome, Crohn’s disease, repeated resections, CIPO, jejunostomy, jejunocolic anastomosis
• Type 1: occurs within days, acute post-op ileus
• Type 2: lasts weeks to months. Due to GI fistulae, abdominal sepsis, GI complications
• Type 3: lifelong. Short-bowel syndrome, chronic obstruction, motility disorders
• Pathophysiological classification: reduced absorption (small bowel disease, short bowel, fistulae), intolerance to EN (obstruction, dysmotility)

Question 9

Palliative PN classifications (3)

Answer 9

• P1: short-term advanced disease (<8 weeks) OR consequences of therapy causing SDS
• P2: support during chemo if hypophagic to improve adherence to chemo
• P3: long-term during palliative care/ advanced disease

Question 10

Prognostic scores for cancer: Glasgow prognostic score, Zubrod performance scale/WHO score, Karnofsky performance score

Answer 10

• Glasgow prognostic score: predictive of outcomes in cancer patients: CRP >10mg/L or albumin <35g/L gives score of 2
• Zubrod/WHO: 0 (asymptomatic), 1 (symptomatic, light activity), 2 (<50% of time in bed), 3 (>50% in bed), 4 (bed-bound), 5 (dead
• Karnofsky score: 0-100. 0 is dead, 100 is normal and no disease. 50 is requires assistance

Question 11

Malignant bowel obstruction: definition, prevalence, mortality, HPN

Answer 11

• MBO: bowel obstruction which can be multi-level or single-level and is more commonly in small bowel (61%) rather than large bowel (33%)
• prevalence: 3-15% cancer patients globally
• mortality: 30-40%
• HPN: 50% survival at 100 days, 22% at 180 days
• Cochrane review concluded that evidence for survival and QoL was very low with HPN, and 12% had complications

Question 12

Composition of PN bags

Answer 12

• go with standard bags for quick discharge, feeds can be adjusted at home is needed
• lipids are well tolerated and don’t need to worry about cholestasis especially is prognosis is <18 months
• omega 3 may be beneficial: reduces NFkB activation (and IL6, CRP), reduces acute phase proteins, inhibits proteolysis (PIF) and fat oxidation, increases appetite and may also induce cytotoxicity in cancer cells by promoting apoptosis

Question 13

Clinical issues to consider with PN

Answer 13

• how much IV fluid? (should be 30-35 mL/kg/day)
• insulin for diabetes
• management of symptoms i.e. post-surgery may need codeine phosphate which can affect gut motility
• access issues: will we be able to get hold of the bags they need?

Question 14

Follow-up with patient and stopping HPN

Answer 14

• Follow up 2-4 weeks post-discharge and as needed after that. If discharged to hospice, liaison with the palliative care team would be enough
• Stopping HPN: if patient and carer believes the cons outweigh the pros (fluids and medications can still be delivered). Can also be stopped if recover digestive function!