tions, was injected intracutaneously on both sides
of the scar of the diagnostic excision. Immediately
after the
99m
Tc-nanocolloid injections, dynamic
acquisition (20 frames of 60 s, 256
¥
256 matrix)
was started. Anterior and lateral static views
were obtained after 1–2 h. The location of the
sentinel node was checked with the hand-held
gamma detector (TecProbe 2000, Stratec Electron-
ic GmbH, Birkenfeld, Germany), and was marked
on the skin with a cobalt-57 penmarker. Lympho-
scintigraphy was performed with a single-head
rectangular gamma camera (Elscint 609) equip-
ped with a low-energy, high-resolution collimator.
Images were obtained with a symmetrical 10%
window over the 140-keV
99m
Tc ene r gy peak. The
gamma probe was used intra-operatively to again
locate the sentinel node. This was done after wide
re-excision of the primary lesion to minimise
background radiation. Once the sentinel node has
been excised, the lymphatic basin was checked for
any remaining radioactivity and the radioactivity
Materials and Methods
Between January 1995 and April 1998, 80 patients
with a malignant melanoma, but otherwise in
good clinical health, underwent lymphoscinti-
graphy for lymphatic mapping and sentinel node
biopsy. None of them had palpable lymph nodes
on clinical examination. All patients satisfied the
following criteria.They had a histologically proven
malignant melanoma, which had been excised
with a small surgical margin.No skin grafting had
been performed and the diagnostic excision had
taken place less than 2 months prior to the sentinel
node procedure. A wider excision of the primary
site was performed simultaneously with the
sentinel node procedure. Pregnancy was exclud-
ed. Detailed patient characteristics are listed in
Table 1.
On the day of surgery an average amount of
80 MBq
99m
Tc-nanocolloid (Nycomed Amersham,
plc) in 0.8 ml saline, divided in four equal por-
chapter
12
172
Characteristics
Number
Pos. SN
a
Sex
35 male/45 female
Age at diagnosis
46.7 years
Age range at diagnosis
18– 81 years
Anatomic location
b
Back, thorax
29
5
Scalp, neck, upper arm
15
4
Lower trunk, leg, foot
30
3
Face, l ower arm, hand
6
1
Breslow thickness
< 0.76 mm
1
0.76 –1.00 mm
4
1.01 –1.50 mm
26
3
1.51 –3.00 mm
31
5
3.00 –4.00 mm
8
1
> 4.00 mm
10
4
Clark level
II
4
III
23
4
IV
49
8
V
4
1
Histologic subtype
Superficial spreading melanoma
38
4
Nodular melanoma
22
5
Amelanotic melanoma
1
1
Lentigo malignant melanoma
1
Malignant melanoma
18
3
a
Pos. SN = tumour positive sentinel node.
b
Classification into anatomical regions listed according to increasing risk of death.
Ta ble 1.
Clinical variables and histo-
pathological data of 80 patients
with a malignant melanoma
without palpable lymph nodes
(Garbe et al., 1995 [26])
.
.
.
.
.
.
.
.
.
.
