Cytology-histology correlation, time to diagnosis and time to therapy when cytology is performed in addition to biopsies in malignant spinal lesions of previously unknown malignant disease.

e14007 Background: Metastatic spinal lesions are the first manifestation of malignant disease in up to 30% of patients (pts). Spinal care, diagnostic evaluation and initiation of systemic therapy are crucial for outcome in pts with advanced cancer. Histopathology (HP) from bone specimens is time consuming and decalcification procedure can hamper diagnostic information. The additional evaluation of spinal lesions by cytopathology (CP) has the potential to reduce time to diagnosis (TTD) and time to therapy (TTT). Therefore, we performed simultaneous analysis of CP and HP specimens from suspected malignant spinal lesions to evaluate the diagnostic value of additional CP. This work was supported by the German Society for Spine Surgery (DWG). Methods: We obtained CP specimens by transpedicular, intralesional aspiration through a Yamshidi needle or touch preparation from solid tissue samples. CP and HP specimens from spinal lesions were evaluated in parallel in 54 pts (CP/HP group). We analyzed sensitivity and specificity of CP in reference to HP. Furthermore, we compared the TTD and TTT of CP/HP group with a retrospective cohort of 103 patients in whom only HP was performed (HP group). Results: The collection of CP samples was feasible without elongation of surgery time or any complications for the pts. In 52/54 (96%) pts a CP-specimen was successfully obtained. Of the 52 pts analyzed, multiple myeloma was diagnosed in 10 pts, solid malignancy in 34, 1 pt had lymphoma and 7 did not show malignancy. The most common solid malignancies were prostate cancer (n=9), breast cancer (n=5) and adenocarcinoma of the lung (n=5). The sensitivity and specificity of CP in reference to HP is 98% and 71%, respectively. The concordance of CP and HP in differentiating between hematologic or solid neoplastic lesions is 94.2%. TTD in the CP/HP group was significantly shorter compared to HP group (1.7±1.8 and 8.6±3.6 d, respectively; p<0.001). In addition, TTT in the CP/HP group was significantly shorter than in the HP group (19.3±14.4 d and 31.4±24.7 d; p=0.003). In 24.1% of pts a specific tumor therapy was initiated based on CP diagnosis before obtaining the results of HP. Conclusions: The evaluation of CP from malignant spinal lesions shows high sensitivity and concordance with HP and reduced TTD and TTT. Therefore, CP in addition to HP from spinal lesions of suspected malignancy has the potential to improve quality of life and prognosis in pts with advanced cancer. We therefore recommend the implementation of additional CP to HP in previously undiagnosed malignant spinal lesions.