The American Society of Clinical Oncology (ASCO) recently updated its guidelines for the prevention and management of nausea and emesis in cancer patients receiving radiation therapy and chemotherapy.

Nausea and vomiting caused by radiation therapy and chemotherapy can affect the treatment continuation and patient quality of life. Clinicians should ensure optimal management of these symptoms by deploying various antiemetic strategies. Patient response to antiemetic therapy may vary over time, thus timely reassessments and modifications to the strategies are also necessary.

The American Society of Clinical Oncology (ASCO) has updated its guideline to prevent and manage nausea and vomiting in cancer patients.

1. The guideline emphasises on the use of the most effective antiemetic regimens in accordance with the antineoplastic agents or radiotherapy administered.
2. The guidance also suggests the use of the antiemetic regimen with the initial treatment itself rather than waiting to assess response with the less effective ones.

Most notable additions to the guideline include: 

• Inclusion of olanzapine and neurokinin-1 (NK1) receptor antagonists 
• Use of medical marijuana to control nausea and vomiting
• Addition of 2 new antiemetic medications:
  • rolapitant, an NK1 receptor antagonist
  • subcutaneously-administered form of granisetron

The recommendations also include some updates regarding anatomic regions, risk levels, and antiemetic administration schedules for radiation therapy.

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Management of nausea and emesis in cancer patients receiving chemotherapy

A summary of the updated guidelines, which were published in the Journal of Clinical Oncology, is as follows. The strength of respective recommendations is indicated in parentheses (strong or moderate).

High-risk regimens; Cisplatin or the combination of cyclophosphamide and an anthracycline

Inclusion of Olanzapine

As per the updated guideline,

• Olanzapine should be given to adults who receive chemotherapy with a high risk for emesis or who experience breakthrough nausea and vomiting
• Olanzapine should be continued on days 2 to 4 (strong)

The recommendation is backed by high-quality evidence from a randomised, phase 3 study which compared olanzapine against placebo in patients receiving a 3-drug antiemetic regimen of an NK1-receptor antagonist, a 5-HT3-receptor antagonist, and dexamethasone.

Timeframe for Dexamethasone administration

• For adults who receive anthracycline and cyclophosphamide chemotherapy, dexamethasone should be administered only on day 1
• Whereas for adult patients treated with cisplatin and other high-emetic-risk single agents, dexamethasone should be continued on days 2 to 4

Moderate-emetic-risk antineoplastic agents

For adults receiving carboplatin-based chemotherapy or high-dose chemotherapy, NK1 receptor antagonists such as aprepitant, casopitant, and rolapitant have been included in addition to the standard regimen comprising of 5-HT3 receptor antagonist and dexamethasone.

• Dexamethasone is suggested on days 2 to 3 during regimens comprising antineoplastic agents (cyclophosphamide, doxorubicin, oxaliplatin) that are known to cause delayed nausea and vomiting

Low-emetic-risk antineoplastic agents

Patients receiving these agents should be offered a single dose of a 5- HT3 receptor antagonist or a single 8-mg dose of dexamethasone before antineoplastic treatment (moderate).

High-dose chemotherapy and stem cell or bone marrow transplantation

Triplet combination regimen comprising of an NK1 receptor antagonist, a 5-HT3 receptor antagonist, and dexamethasone is recommended in such cases (strong).

Treatment with multiday antineoplastic agents

• Patients on 4- or 5-day cisplatin regimens should be offered a three-drug combination of an NK1 receptor antagonist, a 5-HT3 receptor antagonist, and dexamethasone
• Patients should be administered antiemetics before initiation of treatment and the choice of the antiemetic agent should be made after considering the emetic risk of the antineoplastic agent
• Antiemetics should be administered on each day of the antineoplastic treatment and it should be continued for 2 days after the completion of the antineoplastic regimen (moderate)

Breakthrough nausea and vomiting

Clinicians should re-evaluate factors such emetic risk, disease status and concurrent illnesses, and medications before selecting the best regimen.

• In cases where patients experience nausea or vomiting in spite of optimal prophylaxis, olanzapine should be administered and the standard antiemetic regimen should be continued (moderate)

Note: Clinicians can opt for a drug of a different class if nausea or vomiting persists despite prophylaxis and administration of olanzapine.

• Suitable alternatives include:
  • NK1 receptor antagonist
  • Lorazepam or alprazolam
  • A dopamine receptor antagonist
  • Dronabinol or nabilone

The standard antiemetic regimen should be continued (moderate).

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Management of nausea and emesis in cancer patients receiving radiation therapy

High emetic risk radiation therapy

• Patients in this category should be offered a two-drug combination of a 5-HT3 receptor antagonist and dexamethasone
• The combo should be administered before each fraction and on the day after each fraction if radiation therapy is not planned for that day (strong)

Moderate-emetic-risk radiation therapy

For those receiving moderate risk therapies, a 5-HT3 receptor antagonist is recommended. It should be administered before each fraction, with or without dexamethasone before the first five fractions (moderate).

Upper abdomen subsites of upper- and half-body irradiation can be managed with the above-mentioned recommendation. As craniospinal irradiation involves the upper abdomen, it has been reclassified as moderate emetic risk rather than low emetic risk.

Low and minimal-emetic-risk radiation therapy

• When radiation therapy is given to the brain, rescue dexamethasone therapy can be administered
• For other regions such as head, neck, thorax, pelvis, and cases with minimal-emetic-risk radiation therapy, rescue therapy with a 5-HT3 receptor antagonist, dexamethasone, or a dopamine receptor antagonist is warranted

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Management of nausea and emesis in Paediatric patients

High-emetic-risk antineoplastic agents

• A three-drug combination of a 5-HT3 receptor antagonist, dexamethasone, and aprepitant is recommended for children receiving this regimen
• For those who are unable to receive aprepitant, a two-drug combination of a 5-HT3 receptor antagonist and dexamethasone can be beneficial 
• Two-drug combination of palonosetron and aprepitant is recommended in children unable to receive dexamethasone

Moderate-emetic-risk antineoplastic agents

• A two-drug combination of a 5-HT3 receptor antagonist and dexamethasone should be offered
• In children unable to receive dexamethasone, a two-drug combination of a 5-HT3 receptor antagonist and aprepitant is recommended

Low and minimal-emetic-risk antineoplastic agents

As per the updated guideline,

• Ondansetron or granisetron can be administered in low-risk settings
• No prophylaxis is required in cases of minimal emetic risk

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Some miscellaneous recommendations as per the updated guideline

• Routine antiemetic prophylaxis is not required in patients receiving antineoplastic agents with minimal emetic risk (moderate)
• For patients receiving combination therapy, the antiemetic choice should be made in accordance with the component antineoplastic agent with greatest emetic risk (moderate)
• Even though Lorazepam can be used as an adjunct in antiemetic therapies, it is not recommended as a single-agent antiemetic (moderate)

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Cannabis and medical marijuana as antiemetic

As per the new guidance, there is insufficient evidence for the use of Cannabis or medical marijuana as an antiemetic agent. Hence the drug is currently not recommended. However, in cases resistant to standard antiemetic therapies, the guidance supports the use of FDA approved prescription cannabinoids, dronabinol or nabilone.

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Anticipatory nausea & vomiting

• In cases of anticipatory nausea and vomiting, clinicians should use the best antiemetic regimen with the initial treatment itself rather than waiting to assess response with the less effective ones
• Behavioural therapy with systematic desensitisation can also be offered (moderate)

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Concurrent radiation and antineoplastic agent therapy

Patients should receive antiemetic therapy that is appropriate for the emetic risk level of antineoplastic agents unless the risk level of radiation therapy is higher (moderate).