Neuroendocrine tumors Histopathology based on cases presentations

1. NEUROENDOCRINE TUMOURS; CASE-
BASED DISCUSSION
PRESENTED BY;
DR. MONA RASHED
CONSULTANT HISTOPATHOLOGY
KING KHALID HOSPITAL-NAJRAN

2. INTRODUCTION
Neuroendocrine tumors (also called NETs) represent about 0.5% of
all newly diagnosed malignancies.
Neuroendocrine tumors are rare, slow-growing tumors that originate
in cells of the diffuse neuroendocrine system. They occur most
frequently in tissues derived from the embryonic gut.

3. PATHOLOGY OF NET:
• Neuroendocrine tumors have specific histological and
immunohistochemical features based on their anatomical location and
endocrine cell type.
• In the gastric or intestinal wall, they may occur as firm white, yellow, or
gray nodules and may be intramural masses or may protrude into the
lumen as polypoid nodules.

4. The overlying gastric or
intestinal mucosa may be
intact or have focal
ulceration.

5. • Neuroendocrine cells have uniform nuclei
and abundant granular or faintly staining
(clear) cytoplasm.
• They are present as solid or small
trabecular clusters or are dispersed among
other cells, which may make them difficult
to recognize in sections stained with
hematoxylin and eosin; immunostaining
enables their exact identification.

6. NEUROENDOCRINE NEOPLASM / TUMOR
(WHO CLASSIFICATION - 2019)
• 1-Neuroendocrine tumor (NET):
• NET, grade 1 (G1): well differentiated low grade
• NET, G2: well differentiated intermediate grade
• NET, G3: well differentiated high grade
• 2-Neuroendocrine carcinoma, small cell type (SCNEC)
• 3-Neuroendocrine carcinoma, large cell type (LCNEC)
• 4-Mixed neuroendocrine – non-neuroendocrine neoplasm (MiNEN)

7. NNEUROENDOCRINE TUMORS/ NEOPLASMS
DIFFERENTIATION & GRADING

8. CASE-1
• Female ; 36 years old, she has a palpable rectal mass, submucosal
“mostly lipoma”
• Received at the histopathology department as one polypoid mass
measuring 1.2 x 1 x 0.8 cm, with firm consistency and yellowish
color on cut section.

11. Ki67
Synaptophysin
Chromogranin

12. FINAL
DIAGNOSIS
Rectal, neuroendocrine
tumor
Well differentiated,
who grade I
Ki67 < 3%

13. CASE - 2
• Male patient , 62 years old
• Clinically presented with abdominal pain and conistipation
• Gastric and duodenal endoscopic biopsy and gastric polyp
endoscopic biopsy

14. • The gastric polyp show antral gastric mucosa overlying well
circumscribed tumor composed of nests of cells surrounded by
abundant vascular stroma
• The case is changing; differential diagnosis included:
1- GIST
2- Gastric carcinoma
3- Neuroendocrine tumor
4- Inflammatory myo-fibrobastic tumour

16. CK/AE1-AE3

17. DOG-1 H-CALDESMONE
CD-34

18. CHROMOGRANIN
KI-76
SYNAPTOPHYSIN

19. IMMUNOHISTOCHEMISTRY STUDY:
NEOPLASM POSITIVE:
• CHROMOGRANIN
• SYNAPTOPHYSIN
• KI 67 <3%
NEOPLASM NEGATIVE:
• CK/AE1-AE3
• DOG-1
• CD34
• H-CALDESMONE

20. FINAL
DIAGNOSIS
GASTRIC
NEUROENDOCRINE TUMOR
WELL- DIFFERENTIATED,
GRADE I

21. THANK YOU VERY MUCH