Goblet cell carcinoid tumors of the appendix: An overview

Table 1 Comparison of clinicopathological features of goblet cell carcinoid, carcinoid & adenocarcinoma

	Goblet cell carcinoid	Carcinoid	Adenocarcinoma
Clinical features
Age	5th-6th decade	4th decade	7th decade
Carcinoid syndrome	No	Yes	No
Primary symptoms	Acute appendicitis	Acute appendicitis	Mass
Gross appearance	> 2 cm, ill defined thickening	< 2 cm	> 2 cm, well defined mass
Microscopic appearance
Morphology	Clusters of goblet or signet-ring cells separated by fibrosis/pools of mucin	Nests of small cells	Well-formed glands to sheets of poorly differentiated signet-ring cells
Atypia	Minimal	Minimal	Marked
Mitosis	Rare	Rare	Increased
Vascular and perineural invasion	Present	Absent	Present
Infiltrative margins	Present	Absent	Present
Special stains
Argyrophil	Positive	Positive	Usually negative
Argentaffin	Negative	Positive	Negative
Mucicarmine/PAS/PASD	Positive in goblet cells	Negative	Positive
IHC
CEA	+	-	+
CDX2	+	-	+
CAM5.2	+	-	+
CK20	±	-	+
CK7	±	-	-
CK19	+	-	-
Neuroendocrine markers	±	±	-
Math1 and HD5	+	-	+
p53, p16	-	-	+
Molecular pathology
DPC4, Kras, β-catenin mutation and p53 over expression	-	-	+