tubule neck dysplasia
Tuesday 2 October 2012
The identification of the precursor lesion of the diffuse type of gastric cancer has been a difficult task.
This carcinoma, characterised by single cell infiltration of the lamina propria, is mainly associated with non-metaplastic mucosa.
Early observers noticed that tumour cells seem to bud off the glandular neck regions of tortuous gastric tubules.
Closer observation of the tubules revealed crowding of the neck region by enlarged clear cells. The nuclei of these cells also appear to be enlarged, vacuolated with prominent nuclei and loss of nuclear polarity, and look very similar to their invasive counterpart.
These changes are believed to represent precancerous lesions and have been reported as "tubule neck dysplasia" or "globoid dysplasia".
One animal experiment was successful at reproducing these changes.
Another study also attempted to characterise different histological grades based on the degree of cytological atypia and the extent of glandular involvement.
However, tubule neck dysplasia is very subtle and not readily recognisable, even on morphometric analysis.
Thus although pathologists have no hesitation in recommending excision of conventionally dysplastic lesions, even those that recognise tubule neck dysplasia would not recommend resection if it appeared in a biopsy sample.
Polyps of this type of dysplasia either do not seem to exist or are unrecognised.
gastric epithelial dysplasia