ORIGINAL ARTICLESDetection of micrometastases in sentinel lymph nodes from melanoma patients: direct comparison of multimarker molecular and immunopathological methods Rimoldi, Donataa; Lemoine, Robertb; Kurt, Anne-Marieg; Salvi, Suzannea; Berset, Magalid; Matter, Mauricec; Roche, Brunoh; Cerottini, Jean-Philipped; Guggisberg, Davidd; Krischer, Joachimi; Braun, Ralphi; Willi, Jean-Pierree; Antonescu, Christiane; Slosman, Danielj; Lejeune, Ferdy Jf; Liénard, Daniellea,ffor the Groupe Mélanome LémaniqueAuthor Information aLudwig Institute for Cancer Research, Lausanne Branch, University of Lausanne, Epalinges, Switzerland, bDepartment of Pathology, cDepartment of Surgery, dDepartment of Dermatology, eDepartment of Nuclear Medicine and fMultidisciplinary Oncology Center, University Hospital (CHUV), Lausanne, Switzerland, and gDepartment of Pathology, hDepartment of Surgery, iDepartment of Dermatology and jDepartment of Nuclear Medicine, University Hospital (HUG), Geneva, Switzerland. kIn addition to the authors, members of the Groupe Mélanome Lémanique who participated to the study are R. G. Panizzon, Dermatology Department, A. Bischoff-Delaloye, Nuclear Medicine Department, and F. Delacretaz, Pathology Department, University Hospital (CHUV), Lausanne, Switzerland; J.-H. Saurat, M. Brouard, P. Chavaz, L. French and V. Piguet, Dermatology Department, P.-Y. Dietrich, Oncology Department, and B. Borisch, Pathology Department, University Hospital (HUG), Geneva, Switzerland; J.-C. Cerottini, P. Romero and D. Speiser, Ludwig Institute for Cancer Research, Lausanne Branch, Lausanne, Switzerland; C. Ruegg, Multidisciplinary Oncology Center, Lausanne, Switzerland. Correspondence and requests for reprints to Donata Rimoldi, Ludwig Institute for Cancer Research, Chemin des Boveresses 155, CH-1066 Epalinges, Switzerland. Tel: +41 21 692 5981; fax: +41 21 653 4474; e-mail: [email protected] Received 28 October 2002 Accepted 31 March 2003 Melanoma Research: October 2003 - Volume 13 - Issue 5 - p 511-520 Buy Abstract The technique of sentinel lymph node (SLN) dissection is a reliable predictor of metastatic disease in the lymphatic basin draining the primary melanoma. Reverse transcription-polymerase chain reaction (RT-PCR) is emerging as a highly sensitive technique to detect micrometastases in SLNs, but its specificity has been questioned. A prospective SLN study in melanoma patients was undertaken to compare in detail immunopathological versus molecular detection methods. Sentinel lymphadenectomy was performed on 57 patients, with a total of 71 SLNs analysed. SLNs were cut in slices, which were alternatively subjected to parallel multimarker analysis by microscopy (haematoxylin and eosin and immunohistochemistry for HMB-45, S100, tyrosinase and Melan-A/MART-1) and RT-PCR (for tyrosinase and Melan-A/MART-1). Metastases were detected by both methods in 23% of the SLNs (28% of the patients). The combined use of Melan-A/MART-1 and tyrosinase amplification increased the sensitivity of PCR detection of microscopically proven micrometastases. Of the 55 immunopathologically negative SLNs, 25 were found to be positive on RT-PCR. Notably, eight of these SLNs contained naevi, all of which were positive for tyrosinase and/or Melan-A/MART-1, as detected at both mRNA and protein level. The remaining 41% of the SLNs were negative on both immunohistochemistry and RT-PCR. Analysis of a series of adjacent non-SLNs by RT-PCR confirmed the concept of orderly progression of metastasis. Clinical follow-up showed disease recurrence in 12% of the RT-PCR-positive immunopathology-negative SLNs, indicating that even an extensive immunohistochemical analysis may underestimate the presence of micrometastases. However, molecular analyses, albeit more sensitive, need to be further improved in order to attain acceptable specificity before they can be applied diagnostically. © 2003 Lippincott Williams & Wilkins, Inc.