Mucinous cyst adenoma is the most common form of benign neoplasms of the appendix, with an incidence of 0.
The final histology revealed mucinous cyst adenoma of the appendix (fig 2).
In their study report, the researchers write that their study also showed promising results in detecting mucinous cyst
lesions, which are a precursor to cancer.
Glandular cells in the aspirate, when present, can be a marker for a mucinous cyst.
Pochapin said he was "stunned" at the high proportion (43%) of the 21 patients who turned out to have mucinous cysts.
A biopsy of tissue might miss some important areas of cancer, but an aspiration of a fluid mucinous cyst
is a good sample.
The second, more plausible, theory is that these tumors arise from an invagination of multipotential mesothelium with subsequent mucinous metaplasia of the mesothelial lining cells, giving rise to a mucinous cyst
that enlarges to form a cystic tumor The presence of the flat to low cuboidal cells, positive for calretinin, a mesothelial marker, supports this origin.
Those results show a strong sensitivity and specificity for the 3 categories of cysts (respectively 69% and 100% for serous cystadenomas, 91% and 95% for mucinous cysts
and 43% and 100% for pseudocysts).
Chang, at UC Irvine report that the use of Cellvizio demonstrated 100% positive predictive value and 100% specificity in characterizing mucinous cysts
thanks to the visualization of papillary projections, also called papillae.
These include mucinous cysts
, benign mucocele-like lesions, mucinous spherulosis, mucocele-like lesion with atypia (atypical ductal hyperplasia), mucocele-like lesion with ductal carcinoma in situ, myxoid changes in fibroadenoma, ductal carcinoma, and lobular carcinomas with mucinous features.
Only 1 case contained small foci of mucinous change within the tumor (Figure 6), together with scattered mucinous cysts