Page 26 - 89Zr-Immuno-PET:Towards a Clinical Tool to Guide Antibody-based Therapy in Cancer

Chapter 2
with head and neck squamous cell carcinoma (HNSCC), who were at high risk of having neck lymph node metastases. Twenty HNSCC patients underwent 89Zr- cmAb U36 immuno-PET prior to surgery. Immuno-PET detected all primary tumors (n = 17) as well as lymph node metastases in 18 of 25 positive neck levels. It was concluded that for the detection of HNSCC lymph node metastases (and probably distant metastases), immuno-PET with 89Zr-cmAb U36 performs at least as good as CT or MRI.
No radiation dose estimates have been previously described for 89Zr- cmAb U36 or other 89Zr-labeled mAbs. Therefore, the aim of the present study was to assess safety, biodistribution, radiation dose, and the potential for quantification of immuno-PET with 89Zr-cmAb U36 in HNSCC patients using data of aforementioned clinical trial.
MATERIALS AND METHODS
Patient Study
Twenty patients (8 females and 12 males) with histologically proven HNSCC (Table 1), at high risk of having neck lymph node metastasis and, therefore, planned to undergo neck dissection with or without resection of the primary tumor, participated in this study. Other eligibility criteria have been decribed previously (2). Patients received cmAb U36 IgG radiolabeled with 89Zr (74.9 ± 0.6 MBq). The total administered cmAb U36 dosage was 10 mg for all patients. In previous studies, it had been demonstrated that biodistribution is not mAb dose dependent within the range 2 - 52 mg (16,17). Surgery was performed 6-8 days after administration of radiolabeled cmAb U36.
Safety
Prior and up to 6 wk after administration of radiolabeled cmAb U36, routine laboratory analyses were performed, including hemoglobin, hematocrit, mean corpuscular volume, red blood cell count, white blood cell count (including automated differential), platelet count, sodium, potassium, calcium, chloride, creatinine, urea, uric acid, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma glutamyl transferase, albumin, glucose, bilirubin, thyroid stimulating hormone, and urine sediment. Vital signs including pulse rate, blood pressure, temperature, and respiratory rate were recorded before and up to
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