Background: The preoperative evaluation of lymphatic metastasis in patients
with oesophageal cancer is of vital importance in determining a therapeuti
c strategy. The aim of this study was to establish criteria for the preoper
ative diagnosis of lymph node metastases based on the size and shape of nod
es.
Methods: Some 123 patients with intrathoracic oesophageal cancer were studi
ed and 6822 nodes were obtained by extended lymphadenectomy. The nodes were
classified anatomically and their size was measured by the operating surge
on during or immediately after operation. All were examined histologically
and criteria for the diagnosis of metastasis were evaluated.
Results: The size of the lymph nodes varied by anatomical site. Nodes were
smallest in the neck and largest at the tracheal bifurcation. The cut-off v
alue for the diagnosis of metastasis was 5 mm in the neck, 6 mm in the abdo
men and 8 mm in the mediastinum, except for tracheal nodes. Lymph nodes 10
mm or larger tended to become spherical when involved by metastasis.
Conclusion: The incidence of metastasis in each lymph node can be estimated
by its size. Discounting nodes less than 10 mm can lead to an underestimat
ion of the stage of oesophageal cancer during preoperative evaluation.