This document discusses several types of carcinomas including squamous cell carcinoma, adenocarcinoma, mucoid carcinoma, signet ring carcinoma, and basal cell carcinoma. Squamous cell carcinoma originates in squamous epithelium and can occur in the skin, oral cavity, or cervix. Adenocarcinoma originates in glandular tissue and can occur in organs like the colon, stomach, or endometrium. Mucoid carcinoma and signet ring carcinoma are subtypes of adenocarcinoma that differ in their production and location of mucin. Basal cell carcinoma originates from basal cells of the epidermis and commonly occurs on sun exposed areas like the face.

1. Slides of the week

2. Squamous cell carcinoma
 Origin: Squamous epithelium.
 Sites: Skin, Oral cavity, Cervix.
 Gross: Irregular growth fungating, infiltrating
or ulcerating growth.
 Microscopically: Masses and sheets of
malignant squamous epithelial cells containing
keratin nests and separated by C.T.stroma which
infiltrated with inflammatory cells.
 Grading: depends on , % of keratin nests,
mitoses and irregular nuclear pattern

3. Squamous cell carcinoma, Skin

4. Squamous cell carcinoma
Sole of the foot

5. SQUAMOUS CELL CARCINOMA
SCC

6. Squamous cell carcinoma

7. Adenocarcinoma
 Origin: glandular tissue.
 Sites: endocrine, exocrine glands, mucus
membranes, GIT, endometrium.
 Gross: in solid organsirregular infiltrative
growth, in hollow organsfungating, infiltrating
or ulcerating growth.
 Microscopically: irregular glands in size and
shape,lined by malignant cells and separated by
C.T. stroma.
 Grading: depends on tubule formation,
number of mitoses and irregular nuclear pattern.

8. Adenocarcinoma,colon

10. Adenocarcinoma colon

11. Adenocarcinoma colon

12. Adenocarcinoma colon

13. Grading of malignant Tumours

15. Mucoid carcinoma
 Origin: from glandular epithelium.
 Sites: mostly in GIT.
 Grossly: appears as soft gelatinous mass.
 Microscopicaly:
1-Mucoid carcinoma: mucoid differentiation in
an adenocarcinoma  rupture of cells  release
of large amount of extra-cellular mucin.
2-Signet cell carcinoma: cells are distended
with intracellular mucin--. Signet ring cells with
minimal extrapcellular mucin.

16. Mucoid carcinoma, colon

17. Signet ring carcinoma,Stomach

18. Basal cell crcinoma
((Rodent ulcer
 Def: locally malignant tumor arising from the
basal cell layer of epidermis.
 Sites: skin areas exposed to sun as in face.
 Gossly: starts as a papule rodent ulcer
( raised everted edge,rough and necrotic floor,
indurated edge).
 Histologically: invasion of the dermis by
variable sized masses formed of malignant
basaloid cells that form palisade appearance at
the periphery.

19. Basal cell carcinoma ,Face

20. Basal cell carcinoma,Face

21. Basal cell carcinoma