Serous Microcystic Adenoma of the Pancreas

Differential Diagnosis

Serous Microcystic Adenoma	Mucinous Cystic Neoplasm of the Pancreas
Cuboidal clear epithelial lining	Mucinous lining
Occurs in males and females	Nearly all female
Lack ovarian type stroma	Ovarian type stroma
Many small cysts	Oligocystic or unilocular
Usually stellate central scar	Lacks central scar
Glycogen positive, mucin negative	Glycogen negative, mucin positive

Serous Macrocystic / Oligocystic Adenoma	Serous Microcystic Adenoma
Small number of larger, variably sized cysts	Innumerable small, uniform cysts
Lacks prominent scar	Frequent central scar
May occur in adults and infants	Not reported in infants

Serous Microcystic Adenoma	Serous Cystadenocarcinoma of the Pancreas
Circumscribed intrapancreatic mass	Requires vascular invasion, adjacent organ invasion or metastases

Serous adenoma and cystadenocarcinoma are histologically indistinguishable

Rare cases have been reported of resected non-invasive serous cystadenomas that recurred later with metastases

Serous Microcystic Adenoma	Solid Pseudopapillary Neoplasm of the Pancreas
True cysts lined by a single layer of cells	Variable thickness of lining of degenerate spaces
Occurs in males and females	Nearly all female
Median age 60's	Mean age 20's
Glycogen positive	Glycogen negative
Keratin positive	Keratin variable

Clear cell variant of solid pseudopapillary neoplasm is also reported to be glycogen negative

Serous Microcystic Adenoma	Acinar Cell Cystadenocarcinoma of the Pancreas
Lined by clear cells	Lined by cells with granular eosinophilic cytoplasm
Frequent central scar	Lacks central scar
PAS+, diastase sensitive	PAS+, diastase resistant
BCL10, trypsin, chymotrypsin negative	BCL10, trypsin, chymotrypsin positive

Serous Microcystic Adenoma	Lymphangioma
Lined by clear cells	Lined by endothelium
Keratin positive	CD31, CD34, D240 positive

Serous Microcystic Adenoma	Lymphoepithelial Cyst of the Pancreas
Lined by clear cells	Lined by squamous epithelium
Lacks lymphoid stroma	Prominent lymphoid stroma

von Hippel Lindau syndrome is associated with diffuse cystic transformation of the pancreas and occasionally with serous microcystic adenomas