What is the full R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone) chemotherapy regimen, including premedication and supportive care, for a patient with non-Hodgkin lymphoma?

R-CHOP Regimen Details for Non-Hodgkin Lymphoma

The standard R-CHOP-21 regimen consists of rituximab 375 mg/m² IV on day 1, cyclophosphamide 750 mg/m², doxorubicin 50 mg/m², and vincristine 1.4 mg/m² (maximum 2 mg) all IV on day 1, plus oral prednisone 40 mg/m² on days 1-5, administered every 21 days for 6-8 cycles. 1, 2, 3

Pre-Treatment Requirements

Mandatory baseline testing before initiating R-CHOP:

• Hepatitis B surface antigen, core antibody, and surface antibody testing is required before rituximab initiation 2
• Baseline cardiac assessment with ejection fraction measurement 2
• Complete blood count, comprehensive metabolic panel including LDH and uric acid 1
• HIV and hepatitis C screening 1

Premedication Protocol

Standard premedications for rituximab infusion:

• Acetaminophen and diphenhydramine are typically administered 30-60 minutes before rituximab to reduce infusion reactions 3
• Consider corticosteroid premedication for patients with high tumor burden or prior infusion reactions 3

Tumor lysis syndrome prophylaxis:

• Required for patients with high tumor burden: aggressive hydration, allopurinol or rasburicase, and electrolyte monitoring 1

Detailed Administration Schedule

Day 1 of each 21-day cycle:

• Rituximab 375 mg/m² IV infusion (first infusion typically over 4-6 hours; subsequent infusions can be shortened if tolerated) 2, 3
• Cyclophosphamide 750 mg/m² IV over 30-60 minutes 4
• Doxorubicin 50 mg/m² IV push or short infusion 4
• Vincristine 1.4 mg/m² IV push (capped at 2 mg maximum dose) 4

Days 1-5 of each cycle:

• Prednisone 40 mg/m² orally daily 4

Supportive Care During Treatment

Antimicrobial prophylaxis:

• Pneumocystis jirovecii pneumonia (PCP) prophylaxis with trimethoprim-sulfamethoxazole or equivalent throughout treatment and for 6-12 months after completion 1
• Herpes zoster prophylaxis with acyclovir or valacyclovir during treatment 1

Growth factor support:

• Prophylactic granulocyte colony-stimulating factor (G-CSF) is recommended starting day 2-3 of each cycle to prevent febrile neutropenia, particularly in patients over 65 years or those with prior neutropenic complications 1

Antiemetic regimen:

• 5-HT3 antagonist (ondansetron or granisetron) plus dexamethasone on day 1 1
• Continue antiemetics for 2-3 days post-chemotherapy as needed

Monitoring Requirements

During treatment:

• Complete blood count before each cycle; delay treatment if ANC <1,000/μL or platelets <75,000/μL 1
• Avoid dose reductions for hematologic toxicity when possible; use G-CSF support instead 1
• Serial cardiac monitoring during and after treatment completion, particularly for patients receiving cumulative doxorubicin doses 2

Hepatitis B reactivation monitoring:

• Monthly hepatitis B viral load monitoring in patients with positive hepatitis B core antibody, even if surface antigen negative 2
• Initiate antiviral prophylaxis (entecavir or tenofovir) if viral load becomes detectable 2

Treatment Duration

Standard course:

• 6 cycles for limited-stage disease (stage I-II) 1, 2
• 8 cycles for advanced-stage disease (stage III-IV) 1, 2
• Each cycle administered every 21 days (R-CHOP-21 is superior to R-CHOP-14 based on randomized data) 4

Cardiac Dysfunction Modifications

For patients with baseline left ventricular dysfunction or ejection fraction <50%:

• Consider doxorubicin-sparing alternatives: RCEPP, RCDOP, RCNOP, or RCEOP 2
• If anthracycline use is necessary, consider dexrazoxane as cardioprotectant 2
• Increase frequency of cardiac monitoring to every 2 cycles 2

Common Pitfalls to Avoid

• Never cap vincristine at 2 mg in the first dose without institutional protocol support—the standard cap applies to all doses 4
• Do not reduce chemotherapy doses for neutropenia—use G-CSF support instead to maintain dose intensity, which is critical for cure 1
• Do not omit hepatitis B screening—reactivation can be fatal and is preventable with monitoring and prophylaxis 2
• Ensure adequate hydration before cyclophosphamide—hemorrhagic cystitis prophylaxis with mesna is not routinely needed at standard doses but maintain good urine output 1