OT2-05-01: An Open-Label Positron Emission Tomography Study To Investigate and Quantify Brain and Tumor Penetration of Carbon-11-Labeled Lapatinib in Patients with HER2−Overexpressing Advanced or Metastatic Breast Cancer

Background: Patients with HER2−overexpressing (HER2+) breast cancer tend to develop visceral metastases. About a third will develop brain metastases in the course of their disease. Several anticancer agents including trastuzumab are not believed to readily cross the blood-brain barrier (BBB); therefore, central nervous system (CNS) disease progression is emerging as an important clinical problem in this patient population. Although preclinical data indicate that lapatinib brain concentrations are low in healthy animals, probably due to the BBB efflux transporters, observations from clinical studies suggest lapatinib treatment might be associated with reduced CNS tumor growth. One hypothesis is that disruption of the BBB by tumors circumvents the usual protective function of transporters. Alternatively, inhibition of efflux transporters by lapatinib enhances its own accumulation with repeat dosing. The role of lapatinib in prevention of brain metastases is currently being explored in a phase III trial, EGF 111438 (CEREBEL).

Methods: To directly assess if lapatinib penetrates the brain and brain metastases, an open-label non-randomized study using carbon-11-labeled [11C] lapatinib is enrolling patients with HER2+ metastatic breast cancer. A minimum of 10 patients with an ECOG of <3 are grouped into 2 cohorts: with at least one 1-cm diameter brain metastasis or without brain metastases. Two positron emission tomography (PET) scans will be performed in each patient following intravenous administration of a microdose of [11C] lapatinib: in lapatinib-naïve patients and at steady-state lapatinib, after treatment with unlabelled oral lapatinib 1500 mg once daily for 8 days. [11C] lapatinib time-activity curves will be generated for normal brain and brain metastases, the PET volume of distribution in the brain calculated and penetration of [11C] lapatinib into the brain quantified. Analysis of brain PET data is explorative as [11C] lapatinib is a new tracer. Therefore, this study investigates both the difference in lapatinib brain penetration between patients with and without brain metastases, as well as the effect of low and high concentrations of lapatinib on the BBB efflux system.

The study is currently recruiting in one center in the United Kingdom.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr OT2-05-01.

[Skin sensitisation profiles of outpatients with symptoms of respiratory allergies]

AIM

The main objective of the survey was to determine the frequency of the mono and polysensitizations in patients consulting for respiratory allergy, rhinitis or/and asthma. The secondary objectives were to evaluate the severity, the number and the type of the sensitizations, the frequency of the asthma or rhinitis as a function of the sensitizations, the evolution of the sensitizations with age, and identify the principal responsible pneumallergens.

PATIENTS AND METHODS

The multicentric survey included a patient questionnaire allowing the collection and anonymous treatment of data on socio-demographic characteristics, clinical symptoms, cutaneous tests and sensitizations.

RESULTS

A sample of 505 patients, mean age 24 years, consulting for rhinitis or asthma, monosensitized (36%) or polysensitized (64%), was evaluated. The percentage of polysensitized patients was similar in asthmatics, patients with rhinitis, and patients with both asthma and rhinitis (60%, 65%, and 63%, respectively). The mean number of the sensitizations was 2.4 for patients with asthma, 2.6 for those with rhinitis, and 2.6 for patients with both asthma and rhinitis. The greater the severity of the rhinitis or asthma, the higher the number of the sensitizations. Sensitizations to acarids, gramineae and cat were the most frequent. When practioners were asked about their intention to undertake desensitization in polysensitized patients, 52% of them replied positively.

CONCLUSION

Data collected during this survey showed that a large proportion of the patients who consulted for rhinitis or asthma were monosensitized (36%). Sensitization to acarids was the most frequent. Even in polysensitized patients, more than half the practioners said they would use desensitization.