Plasma levels of trastuzumab in gastric cancer: Case report.
Introduction The use of trastuzumab with a fluoropyrimidine and platinum compound is currently the standard first-line treatment of patients with metastatic HER2-positive gastric cancer, but it appears that serum levels of trastuzumab determine the clinical effectiveness of this treatment, affecting progression-free survival and overall survival. Case report We report the case of a patient with metastatic HER2-positivegastric cancer, receiving XELOX (fluoropyrimidine and oxaliplatin) plus trastuzumab at standard doses, who presented sub-therapeutic serum levels during the first two treatment cycles and rapid disease progression (progression-free survival = 5.6 months). Discussion This case reveals a possible cause of poor effectiveness of trastuzumab treatment for metastatic gastric cancer in some patients, namely low circulating levels of the drug. It highlights the importance of monitoring as a possible tool for individual dose adjustment to optimize this therapy.
1 Pharmacy, Complejo Hospitalario Universitario de Canarias, San Cristóbal de La Laguna, Santa Cruz de Tenerife, Spain.
J
J
González-García
2 Oncology, Complejo Hospitalario Universitario de Canarias, San Cristóbal de La Laguna, Santa Cruz de Tenerife, Spain.
B
B
Alonso-Alvarez
1 Pharmacy, Complejo Hospitalario Universitario de Canarias, San Cristóbal de La Laguna, Santa Cruz de Tenerife, Spain.
G J
GJ
Nazco-Casariego
2 Oncology, Complejo Hospitalario Universitario de Canarias, San Cristóbal de La Laguna, Santa Cruz de Tenerife, Spain.
N
N
Batista-López
1 Pharmacy, Complejo Hospitalario Universitario de Canarias, San Cristóbal de La Laguna, Santa Cruz de Tenerife, Spain.
F
F
Guttiérrez-Nicolás
D000074322:Antineoplastic Agents, Immunological / Q000008:administration & dosage / Q000097:blood*; D018572:Disease-Free Survival; D006801:Humans; D008297:Male; D008875:Middle Aged; D018719:Erb-b2 Receptor Tyrosine Kinases; D013274:Stomach Neoplasms / Q000097:blood* / Q000188:drug therapy*; D000068878:Trastuzumab / Q000008:administration & dosage / Q000097:blood*; D016896:Treatment Outcome
D000074322:Antineoplastic Agents, Immunological; D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab
Trastuzumab; gastric cancer; pharmacokinetics