Clinical Medicine & Physiology
Gehan-George (1970) & Boyd (1935) Body Surface Area (BSA) Formula: Oncology Dosing
Calculate high-sample-size oncology Body Surface Area (m^2) for mg/m^2 cytotoxic chemotherapy dosing using Edmund A. Gehan & Stephen L. George’s (1970, NCI standard) 401-subject power law and Edith Boyd’s (1935) log-weight allometric equation.
Why NCI cancer trial protocols standardized on Gehan & George’s 401-subject BSA equation over Du Bois’s 9-subject fit!
Du Bois & Du Bois (1916) derived their famous BSA equation on just NINE subjects (including only one child)! Analyzing 401 direct geometric surface-area measurements across infants, children, and adults for the National Cancer Institute Chemotherapy Program, biostatisticians Edmund A. Gehan and Stephen L. George (1970, Cancer Chemotherapy Reports) established the high-precision oncology reference power law: BSA_GG (m^2) = 0.0235 * (Height_cm^0.42246) * (Weight_kg^0.51456)!
Alongside Gehan-George, pediatricians and pharmacologists cross-check Edith Boyd’s (1935, University of Minnesota) non-constant-exponent equation (with Weight_g = 1,000 * Weight_kg in grams to capture changing infant-to-adult body density): BSA_Boyd (m^2) = 0.0003207 * (Height_cm^0.30) * ((1000 * Weight_kg)^(0.7285 - 0.0188 * LOG10(1000 * Weight_kg)))!
| Oncology Patient Profile | Gehan & George (1970) BSA (m^2) | Boyd (1935) BSA (m^2) | 100 mg/m^2 Chemo Dose (Gehan-George) |
|---|---|---|---|
| Pediatric Patient (115 cm, 22 kg) | 0.8558 m^2 | 0.8617 m^2 | 85.6 mg |
| Standard Adult (175 cm, 75 kg) | 1.9208 m^2 | 1.9217 m^2 | 192.1 mg |
| Obese Adult (170 cm, 115 kg) | 2.3547 m^2 | 2.3695 m^2 | 235.5 mg (Check protocol cap) |
Gehan & George (1970, NCI) Body Surface Area BSA (m^2)
Evaluates 0.0235 * (Height_cm^0.42246) * (Weight_kg^0.51456) across Height B2 (cm) and Weight B3 (kg).
=IF(OR(B2 < 35, B2 > 240, B3 < 1.5, B3 > 300), "Invalid Height (cm) or Weight (kg)", ROUND(0.0235 * (B2 ^ 0.42246) * (B3 ^ 0.51456), 4))Boyd (1935) Allometric Body Surface Area BSA (m^2)
Evaluates 0.0003207 * (Height_cm^0.3) * ((1000 * Weight_kg)^(0.7285 - 0.0188 * LOG10(1000 * Weight_kg))).
=IF(OR(B2 < 35, B2 > 240, B3 < 1.5, B3 > 300), "Invalid Height (cm) or Weight (kg)", ROUND(0.0003207 * (B2 ^ 0.3) * ((1000 * B3) ^ (0.7285 - 0.0188 * LOG10(1000 * B3))), 4))Try the example
Use the original values or change them to test your understanding.