Study objectives: The objective of this study was to evaluate the feasibility of the sentinel lymph node (SLN) biopsy in peripheral clinically stage I or II non-small cell lung cancer (NSCLC) using 99mTc colloid and a hand-held gamma detection probe, associated with a blue dye technique.
Design: Prospective study.
Setting: Royal Brompton Hospital, London, UK; and Hôpital Nord, Saint Etienne, France.
Methods: After thoracotomy, a total of 2 mL patent blue dye mixed with 1,600 μCi 99mTc-albumin or 99mTc-colloid was injected into each quadrant of lung tissue immediately surrounding the tumor. Routine lymphadenectomy was carried out. The first lymph nodes to stain blue or radioactive, if any, were considered SLNs.
Results: Twenty-four patients were evaluated. We successfully identified 17 SLNs in 13 patients (detection rate, 54.2%). Mean time from injection to identification of SLNs was 18 min (range, 5 to 30 min). In nine cases, the SLN was blue and radioactive, in six cases only blue, and in two cases only radioactive. The pathologic status of the SLN reflected the pathologic status of other nodes of the routine lymphadenectomy except one case of false-negative SLN (14%). Four SLNs were in N2 stations (23.5%).
Conclusions: The sentinel node mapping in NSCLC with blue dye and radioisotopic techniques is feasible, but the detection rate has to be improved. This technique is an accurate method of identifying the first node draining a tumor, although it is not yet sufficiently sensitive to have a role in reducing the extent of nodal dissection.