Retrospective study on mixed neuroendocrine non-neuroendocrine neoplasms from five European centres

Table 1 Demographic and clinical-pathological characteristics in patients with a diagnosis of mixed neuroendocrine non-neuroendocrine neoplasm

Variable	Category	n (%)	Variable	Category	n (%)
Gender			Predominant component
	Female	25 (36.2)		NE	27 (39.1)
	Male	44 (63.8)		Non-NE	12 (17.4)
				Equal proportion	7 (10.1)
				NA	23 (33.3)
Disease stage			Morphology of NE component
	Localised	37 (53.6)		Large cell	13 (18.8)
	Advanced	30 (43.5)		Small cell	5 (7.2)
	NA	2 (2.9)		Others	1 (1.4)
				NA	50 (72.4)
Primary tumour site			Grading of NE component
	Colon	22 (31.9)		Grade 1	3 (4.3)
	Oesophagus/OGJ	11 (15.9)		Grade 2	14 (20.3)
	Rectum	8 (11.6)		Grade 3	57 (82.6)
	Small bowel/ICJ	8 (11.6)		NA	3 (4.3)
	Pancreas	6 (8.7)
	Stomach	4 (5.8)	Ki-67 of NE component
	Anus	4 (5.8)		Median	70% (55-68)
	Biliary tract	3 (4.3%)		< 55%	19 (27.5)
	Appendix	2 (1.9)		≥ 55%	37 (53.6)
	Unknown	1 (1.5)		NA	13 (18.8)
			Histology of non-NE component
	Lower GI	44 (63.8)		ADC	51 (39.1)
	Upper GI	15 (21.7)		Adenoma	2 (17.4)
	PB	9 (13)		Carcinoma/SCC	1 (10.1)
	Unknown	1 (1.5)		NA	15 (33.3)
			Grading of non- NE component
				Grade 1	10 (14.5)
				Grade 2	14 (20.3)
				Grade 3	20 (29.0)
				Adenoma	2 (17.4)
				NA	23 (33.3)

Note: the sum of the percentages might not reach 100% due to rounding. ECOG: Eastern Cooperative Oncology Group; PS: Performance status; Loc: Localised stage; Adv: Advanced stage; NE: Neuroendocrine; ADC: Adenocarcinoma; SCC: Squamous cell carcinoma; OE: Oesophageal; OGJ: Oesophago-gastric junction; ICJ: Ileo-caecal junction; Lower GI: Lower gastrointestinal tract; Upper GI: Upper gastrointestinal tract; PB: Pancreatico-biliary tract; NA: Not available.