Detection of regional melanoma metastases by ultrasound B-scan, cytology or tyrosinase RT-PCR of fine-needle aspirates

Abstract

Summary Physical examination and ultrasound B-scan screening are important follow-up procedures in melanoma patients with regional disease. However, they do not allow definite diagnosis of suspicious lesions. Fine-needle aspiration cytology (FNAC) enhances the diagnostic accuracy in such patients but, unfortunately, reaches its technical limits, particularly when very small or necrotic lesions are examined. We therefore tested whether tyrosinase reverse transcription polymerase chain reaction (RT-PCR) of fine-needle aspirates (FNA-PCR) could help to increase diagnostic sensitivity. With clinical follow-up in 69 melanoma patients 81 regional lymph nodes were detected by ultrasound Bscan examination, nine of whom appeared to be palpable. Technically, FNAC was successful in all 81 lymph nodes, while FNA-PCR failed to obtain RNA at detectable levels in two lymph nodes of two patients. Of 79 lesions which have been completely evaluated by B-scan, FNAC and FNA-PCR, 44 proved to be melanoma metastases by histopathology, while the remaining 35 lesions were finally classified as non-specific lymph nodes. Of the 44 melanoma metastases 80% (n = 35) have been detected by B-scan, 90% (n = 39) by FNAC and 100% (n = 44) by FNA-PCR (P < 0.05 vs FNAC, P < 0.005 vs B-scan). In the subclass of lesions with diameters below 10 mm the sensitivities were 72% (n = 13), 78% (n = 14) and 100% (n = 18) respectively. In 35 regional lymph nodes classified as benign lesions, FNAC was always negative while FNA-PCR produced one positive result. Neither of these methods did produce false positive results in 15 control lymph nodes of non-melanoma patients. We conclude, that FNA-PCR might have superior sensitivity as compared to FNAC or ultrasound B-scan, particularly in melanoma lesions with diameters below 10 mm.Keywords: melanoma; ultrasound guided fine needle aspiration cytology (FNAC); tyrosinase reverse transcription polymerase chain reaction (RT-PCR); RT/PCR of fine needle aspiration material (FNA-PCR)

Sonographic evaluation of clinically occult in-transit and satellite metastases from cutaneous malignant melanoma

“…It is interesting to note that the dark colour of the aspirate almost constantly correlates with a cytological diagnosis of melanoma metastasis, which contains large amounts of melanin. Our experience leads us to state, in contrast with other authors [8], that rapidity, high level of sensitivity, low cost and absence of side effects make FNA the procedure of choice to achieve a definitive diagnosis, even in small lesions.…”

“…In accordo con la nostra esperienza, malgrado l'opinione di altri autori [8], la rapidità dell'esecuzione della FNA, la sua alta sensibilità, il basso costo e l'assenza di effetti collaterali la rende procedura di scelta al fine di porre certa diagnosi anche nelle piccole lesioni.…”

Molecular Staging in Stage II and III Melanoma Patients and Its Effect on Long-Term Survival

“…Examination procedures were regarded to be negative if no suspicion of metastatic disease was raised. In case of detection of any suspicious lesion, definitive diagnosis was obtained by fine-needle aspiration cytology 21, 22 and by subsequent histopathologic examination of surgically removed lesions.…”

Clinical Cytology in the Diagnosis and Management of Melanoma

“…In particular, HSP-70 expression is believed to be of value in the identification of melanoma patients with poor prognosis (Kalogeraki et al, 2006). Studies also have shown tyrosinase reverse transcription polymerase chain reaction (RT-PCR) on fine-needle aspirates (FNA-PCR) to increase the diagnostic sensitivity of cytology, when US/ FNAC fails to detect the sentinel node metastasis in melanoma (Voit et al, 1999). Such studies have been performed on exfoliative samples as well.…”

“…More recently, lymph node ultrasound (US) with fine needle aspiration cytology (FNAC) is considered a potential cost effective alternative for an SLNB (Voit et al, 2006;van Akkooi et al, 2010). Although, rare studies have reported very low sensitivity which is attributed to tiny and necrotic lesions (Voit et al, 1999;van Rijk et al, 2006); most authors have emphasized the importance of USguided FNAC in the detection of sentinel lymph node metastasis (Voit et al, 1999(Voit et al, , 2002(Voit et al, , 2006. With a positive cytology of the sentinel node, surgeons can proceed with the direct radical lymph node dissection in patients with melanoma.…”