Cytologic categorization of pancreatic neoplastic mucinous cysts with an assessment of the risk of malignancy: A retrospective study based on the Papanicolaou Society of Cytopathology guidelines

Papanicolaou Society of Cytopathology new guidelines have a greater ability of risk stratification for pancreatic endoscopic ultrasound-guided fine-needle aspiration specimens

“…[14] Smith et al reported 0% for “negative,” 13% for “neoplastic,” 17.4% for “nondiagnostic,” 63.6% for “atypical,” 80% for “suspicious”, and 100% for “positive,” which were comparable to Layfield et al's results, although their study focused only on pancreatic neoplastic mucinous cysts. [15] In our study, we retrospectively re-classified a series of 294 pancreatic EUS-FNA cytology cases, and the risks of malignancy were 18.1% for “negative,” 20.0% for “neoplastic,” 57.1% for “nondiagnostic,” 69.2% for “atypical,” 87.5% for “suspicious,” and 100.0% for “positive,” which were in general agreement with published literatures mentioned above.…”

“…This article confirmed the PSC guidelines stratified the risk of malignancy as demonstrated by Layfield et al and Smith et al [14, 15] To our best knowledge, this study for the first time conducted a comparative study of the PSC guidelines and an old classification system conventionally used in China. Again, it was for the first time to investigate the application of PSC new guidelines on pancreatic EUS-FNA cytology for Chinese population.…”

“…Secondly, the old “negative” category (26.0%) was associated with an appreciably higher risk than the new “negative” (18.1%) as well as its counterparts in other literatures (13% by Layfied et al, 0% by Smith et al [15]). It suggests that the PSC new guidelines have an advantage over the old one by further stratifying the old “negative” category into two distinctive new categories: “nondiagnostic” and “negative.” The former one had a statistically higher risk of malignancy than the latter one, thus decreasing the risk of the real “negative” cases.…”

“…Nevertheless, to our best knowledge, few researchers [4, 14, 15] have applied the PSC new guidelines for a retrospective study of pancreatic EUS-FNA cytology, wherein only hundreds of cases were reviewed. For example, Layfield et al [14] conducted a retrospective study of 317 cases, in which they reported the risk of malignancy associated with each PSC category and confirmed the remarkable ability of risk stratification.…”

“…For example, Layfield et al [14] conducted a retrospective study of 317 cases, in which they reported the risk of malignancy associated with each PSC category and confirmed the remarkable ability of risk stratification. Smith et al [15] also reported the risk of malignancy using the new classification in a study of 127 cases of pancreatic neoplastic mucinous cysts. Saieg et al [4] concluded that the application of PSC guidelines had a greater impact among specimen previously categorized as atypical and suspicious by a comparative study of 155 cases.…”