Presentation on theme: "Toward a molecular intra-operative diagnosis of SLN invasion R Garrel 1, V Burcia 1, J Solassol 2, V Costes 3, E Barbotte 4, D DeVerbizier 5, C Cartier."— Presentation transcript:
Toward a molecular intra-operative diagnosis of SLN invasion R Garrel 1, V Burcia 1, J Solassol 2, V Costes 3, E Barbotte 4, D DeVerbizier 5, C Cartier 1, M Makeieff 1, L Crampette 1, N Boulle 2, T Maudelonde 5 B Guerrier 1. Montpellier ’s Teaching Hospitals FRANCE 1 ENT, 2 Molecular Biology, 3 Pathology, 4 Biostatistics, 5 Nuclear Medicine
Sentinel Lymph Node technique : sampling method n Lymph node Mapping –Lymphoscintigraphy n Lymph node Analysis n Serial sections + Immunohistochemistry n Lymph node Biopsy
Goals of SLN technique 1.staging improvement: n Full histopathological analysis 2. select the right treatment for the right patient n to limit neck dissections to pN+ cases only : ≈ 30% patients
Limitation n The lack of accuracy of the Intraoperative diagnosis – “the Missing Link” n Sensitivity of routine Frozen section – 20 % sensitivity * –In best hands with serial sections : 90 %** n but –loss of materials –Not applicable in routine second surgery *Burcia et al. Otolaryngol Head and Neck Surgery 2010 **Tschopp et al. Otolaryngol Head and Neck Surgery 2005
The Role of molecular diagnosis ? n Advantages of molecular diagnosis for SLN staging Q-PCR –Not operator dependent –Automated → quicken → intraoperative use Questions are : #1 “Is the molecular staging as accurate as the gold standard ? ”. #2 “Which is the best Q-PCR marker ?”
Act 1 : Comparison between Q- PCR and Histopathology.................................................... Garrel et al. Clinical Cancer Research 2006............................................
Matched analysis SN section Snap frozen sections: 5µm/250µm IHC Q-PCR Cyto imprint n 3 cytokeratins : CK 5, 14 et 17
Q-PCR values / Size of SLN metastasis Garrel et al. Clinical Cancer Research 2006
= cutoff Patient Staging (18 patients -71 SLN) SN-SN+ Garrel et al. Clinical Cancer Research 2006
Key points n Results: –Q-PCR staging was as accurate as IHC: n positive neck vs negative neck: 100% se / sp n Background noise –No detection of minute micromestasis < 450 µm n in two patients but this inaccuracy was negated by the presence of larger metastases in another SLN being Q-PCR positive in the same two patients n Discriminatory power of Q-PCR is depending on the marker
ROC curves analysis CK17/ SCCA/ PVA → Pemphigus Vulgaris Ag +++ 100% area under curve 0,000.250.500.751.00 0.00 0.25 0.50 0.75 1.00 PVA (AUC=100) SSC (AUC=97.9)) CK T17 (AUC=93.8) Sensitivity 1-Specificity Solassol and Garrel BJC 2010
Conclusion: PVA as the best Q-PCR marker n Larger cohorts to validate PVA for Q-PCR diagnosis n Evaluate the inter-laboratory variations of accuracy “path the way toward the intraoperative molecular staging of sentinel lymph nodes in head and neck squamous cell carcinomas” MicrometastasisMacrometastasis
Future study assessment of automated technique –Q-PCR –one-step nucleic acid amplification (OSNA) OSNA CK19 → PVA SN in Head and Neck as the gold standard ?