Materials and Methods
In our clinic, to see the drainage from the breast to the axilla
routinely on lymphoscintigraphy and to determine the number of increased
uptake SLNs, first early then 2 hours later delayed imaging is
performed. If the drainage area cannot be detected in the images and no
increased uptake SLN is seen, new images are taken after some time if
necessary but in the COVID-19 pandemic period it was decided by the
surgical and nuclear medicine teams not to take delayed images in order
to shorten the waiting time and hence reduce the risk of viral spread
and transmission. After intradermal and 1 intraparenchymal or
intra/peritumoral injection of 1mCi of 99m Tc labeled nanocolloid
(Navidea Biopharmaceuticals, Dublin) to 4 quadrants around the lesion
for the purpose of marking the SLN on the morning of the operation or
one day before; early (dynamic-SPECT) and 2 hours later delayed (static)
images are taken in the Nuclear Medicine unit. The patient is then taken
into operation and intraoperative SLNs are searched with a gamma
detector.
In both groups, number of lesion increased uptake observed in the
lymphoscintigraphy, early/delayed increased uptake rate, SLN detection
rate, sensitivity, specificity, negative predictive value (NPV),
positive predictive value (PPV) of SLNB process, number of positive SLN,
axillary dissection, axillary malignant lymph node, age, tumor
characteristics (T stage, receptor status) and neoadjuvant therapy
status were examined in patients. In the study the effect of taking
delayed images on lymphoscintigraphy on SLN biopsy success was
investigated.
Lymphoscintigraphy reports were examined by scanning electronic files.
Micrometastatic lymph nodes were not included in the false negativity
rate (FNR). The study protocol was approved by the ethics committee of
our institution and the ethics committee approval number is 95/27.05.20.