Sentinel node biopsy procedures with an analysis of recurrence patterns and prognosis in melanoma patients: technical advantages using computer-assisted gamma probe with adjustable collimation.
The purpose of this study was to investigate whether a computer-assisted gamma probe with adjustable collimation could aid in the detection of sentinel nodes (SNs) and to analyse the patterns of recurrence and prognosis in SN-positive and SN-negative cases. We analysed 385 SN biopsies. The SN identification rate was 87.2% using preoperative lymphoscintigraphy and blue dye, 93.9% using preoperative lymphoscintigraphy, blue dye and different probes, and 100% using preoperative lymphoscintigraphy, blue dye and a computer-assisted probe with adjustable collimation. The computer-assisted probe was particularly advantageous in cases where the melanoma was located very close to the SN and in cases of deep-seated nodes or nodes with low uptake, due to the possibility of changing the collimation during the procedure. The SN-positive rate according to the thickness of the primary melanoma was 1.7% for melanomas < or = 1 mm in thickness and 27.5% for melanomas > or = 1 mm. In 4.9% of cases we identified nodes outside the regional nodal basin. In one case we found a micrometastasis in a blue and hot interval node of the lateral abdominal wall. Analysing the node counts registered by the computer-assisted probe, we verified that the blue-positive node for tumour metastases was not the most radioactive node in the field in six out of 52 positive cases (11.5%). Distant metastases were present in 2.0% of SN-negative patients, and in 24% of SN-positive patients (P < 0.001). Highly statistically significant differences were found between SN-negative and SN-positive patients in both the 3 year disease-free survival (86.3% versus 49.2%) and the 3 year disease-specific survival (92.3% versus 77.1%) (P < 0.001).
Borgognoni
Lorenzo
L
Plastic Surgery Unit--Regional Melanoma Referral Centre, St M. Annunziata Hospital, Florence, Italy. lorenzo.borgognoni@asf.toscana.it
Urso
Carmelo
C
Vaggelli
Luca
L
Brandani
Paola
P
Gerlini
Gianni
G
Reali
Umberto Maria
UM
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003936:Diagnosis, Computer-Assisted / Q000295:instrumentation*; D006801:Humans; D008545:Melanoma / Q000175:diagnosis* / Q000473:pathology*; D008875:Middle Aged; D009385:Neoplastic Processes; D011379:Prognosis; D012008:Recurrence; D021701:Sentinel Lymph Node Biopsy / Q000379:methods*; D013057:Spectrum Analysis; D015996:Survival Rate