2. • Basaloid squamous cell carcinoma (BSCC) as
defined by the World Health Organization is an
aggressive, high-grade, variant of squamous cell
carcinoma (SCC) composed of both basaloid and
squamous components.
• It is a recently described squamous cell carcinoma
varient that arise primarily in the upper
aerodigestive tract, with a prediliction for the
larynx, hypopharynx and tongue base.
3. • Basaloid squamous cell carcinoma is a rare variant
of squamous cell carcinoma with more than 200
cases, which have been published since its first
description in 1986 by Wain et al.
4. • Etiology and pathogenesis of basaloid squamous
cell carcinoma is similar to conventional squamous
cell carcinoma.
• Most patients have a long history of smoking and
alcohol drinking.
• In some cases there was a history of previous
radiation to the head and neck region .
• Both represent independent risk factors for the
development of squamous cell carcinoma.
5. • Smokeless tobacco and other exogenous
carcinogens such as occupational, environmental
and nutritional factors may also play role in the
pathogenesis of this cancer.
• EBV was detected in few cases using in situ
hybridization technique from nasopharyngeal sites.
• Recent studies detected a higher frequency of HPV
and HSV in basaloid tumors than in conventional
squamous cell carcinomas of the head and neck.
6. • Basaloid squamous cell carcinoma tends to
occur in persons 40 to 85 years of age.
• It occurs more commonly in males than in
females.
• The lesion clinically appears as a fungating
mass or ulcer and may be painful or interfere
with swallowing.
• Approximately two- third of cases are
diagnosed at an advanced clinical stage.
7. • As its name connotes basaloid squamous cell
carcinoma has two microscopic components.
• The first is a superficial, well differentiated or
moderately differentiated squamous cell
carcinoma, often with surface ulceration,
multifocal origin and areas of carcinoma in
situ.
• The second deeper component is an invasive
basaloid epithelium arranged in islands, cords
and gland like lobules.
8. • This deeper tumour often shows palisading of
peripheral cells, central necrosis and occasional
squamous differentiation.
• The interface between the two components is
typically sharp and distinct, but gradual
transition from squamous to basaloid cell may
be seen ocassionally.
• The tumour islands are often surrounded by
mucoid stroma(basal lamina material)
9. • One of the major features of this tumor is that the
cells exhibit high nucleocytoplasmic ratio and often
have dense hyperchromatic nuclei and
comedonecrosis may be seen in these tumor,
14. • Adenoid cystic carcinoma (ACC, solid variant)
shows groups of cuboidal cells, with dark nuclei.
• ACC lacks areas of squamous differentiation,
cytologic and nuclear atypia; antibodies to CD117
react with most ACCs.
• To differentiate BSCC from ACC (solid variant) we
have applied CD117 because ACCs are positive for
CD117 whereas BSCCs are not.
15. • Adenosquamous carcinoma shows glandular structures
lined by basaloid, columnar or mucin-secreting cells.
Intracytoplasmic mucin is demonstrated by
mucicarmine staining.
• Basal cell adenocarcinoma shows two forms of cells,
usually intermingled with each other-small round cells
and large polygonal cells. For the diagnosis of
carcinoma, there should be more than 4-5 mitotic
figures per 10 high-power fields.
• Basal cell ameloblastoma shows islands of
odontogenic epithelium lined peripherally by cuboidal
cells, surrounding central uniform basaloid-appearing
cells. There is absence of central comedo necrosis and
any squamous component.
16. • The immunoprofile of these tumors show consistent
positive staining to high molecular weight
cytokeratin antibody 34βE12, KL1, and MNF116,
and focal staining for vimentin, EMA, CAM5.2,
CK7, CEA, S100and GFAP,
• and negative immunostaining for CK20,
chromogranin, synaptophysin, BCL2,
and Ber-EP4.
• Actin staining was positive in the basaloid cells
and some cases were positive
for CD99.
17. • SCC shows positive staining to Cytokeratin (CK) 13
where as basaloid cells in BSCC shows no
immunoreactivity.
• Studies shows higher p53 positivity in BSCC when
compared with SCC.
• Similarly, increased expressions of Matrix
Metalloproteinase (MMP), MMP-1, MMP-2 and
MMP-9 were reported in BSCC than in SCC,
suggesting a more aggressive behavior of BSCC
than SCC
18. • BSCC is a distinct clinicopathological entity whose
diagnosis still remains on haematoxylin and eosin
sections by recognizing the defined histological
criteria described two decades ago.
• However, its aggressive clinical behaviour
reiterates prompt diagnosis and treatment.
• Immunohistochemistry may be a useful diagnostic
tool in recognizing such lesions at an early stage.
19. • There is no established consensus for treatment.
Surgery of the tumour and the lymph nodes
associated with radiotherapy is usually seen in
most of the literature.
• Although considerable controversy still exists
regarding the comparative analysis of the clinical
course and prognosis of BSCC and conventional
SCC.
• Studies have proven that BSCC is a high-grade
variant of conventional SCC, associated with
poorer prognosis and increased rate of recurrence.
• Therefore, rare lesion such as BSCC must be
reported for the better understanding of the nature
of such tumours.
