-Chemosensitivity testing in gynecologic oncology. Experiences with an ATP bioluminescence assay-

In the present study, our first experiences with the ATP Tumour Chemosensitivity Assay (ATP-TCA), a novel method for pretherapeutic drug testing, are reported. During one year, a total of 111 samples obtained from patients suffering from different gynaecological malignancies (ovary: 53, breast: 41, others: 17) were sent for chemosensitivity testing. The quality of 104 single cell suspensions was sufficient for further processing. Evaluability rates ranged from 71% (breast cancers and non-ovarian tumours) to 83% (ovarian cancers) with an average of 77%. Evaluability of recurrences was slightly better compared to primaries. A total of 18 different antineoplastic agents and 67 drug combinations was used for in vitro testing with an average of 12.4 drugs/combinations tested per each sample (ovary: 14.8, breast: 9.7, others: 10.2). In 70 of 111 cases, the ATP-TCA was followed by chemotherapy with 44 cases treated in respect of the assay results and 29 cases receiving an antineoplastic regime, which differed from the standard treatment protocol. Compared to untreated patients, recurrences were treated more frequently based on the ATP-TCA, with a majority receiving an alternative protocol as proposed by the assay. In ovarian carcinoma, chemosensitivity testing was of particular importance for the further therapy. 41 of 53 patients were treated by chemotherapy with 29 therapies basing on the results of the assay (alternative protocol: 17). The good correlation of the ATP-TCA and the individual clinical course of the patients was demonstrated by two case reports of recurrent ovarian carcinomas, one of them responding well to platinum-based combinations and the other presenting in vitro and in vivo platinum-resistance. In conclusion, our first experiences with the ATP-TCA were promising. Our results, however, warrant confirmation by studies with a sufficient number of cases and an extended observation period.