Apport de la scintigraphie au 99mTc-dépréotide pour le diagnostic de lésions osseuses secondaires dans le cancer bronchopulmonaire non à petites cellules stade III–IV

Methods Nineteen patients (13 M and 6 F, mean age 59 years) with proven NSCLC, suspected to have stage III or IV were enrolled prospectively. All patients underwent whole body 99m Tc-HMDP and 99m Tc-D scintigraphy to detect bone metastases within a mean interval of 14 days. Each focal uptake of 99m Tc-D or 99m Tc-HMDP was considered benign or malignant, leading to positive or negative diagnosis for bone involvement. The final diagnosis of bone metastases was established by a lung specialist, on the basis of additional imaging modalities and of 12 months follow-up. Results Twelve bone lesions were identified by 99m Tc-D scintigraphy, 10 were classified as bone metastases and two were classified as inflammatory bone lesions. Four patients were metastatic. Fifty eight bone lesions were detected by 99m Tc-HMDP scintigraphy, 26 of whom were considered malignant, eight patients were thus considered metastatic. Thereby, the two nuclear medicine modalities were concordant for 13 patients, that is 68% of cases and were discordant for six patients, representing 32% of cases. Diagnostic sensitivity, specificity and accuracy of depreotide scintigraphy and 99m Tc-HMDP bone scintigraphy were 75% for both, 93.3 and 73.3%, and 89.5 and 73.3% respectively. Conclusion Our data suggest that depreotide scintigraphy with the same sensitivity, a better accuracy and specificity than those of 99m Tc-HMDP bone scan can detect metastatic bone lesions in patients with NSCLC suspected to have stage III or IV disease.