Squamous cell carcinoma skin

Squamous cell carcinoma (SCC)
Dr Nabeel Yahiya
Kottayam Medical college

 skin cancer is the most common of all cancers
 97% of these are nonmelanoma skin cancer
(NMSC).
 Basal cell carcinoma (BCC) comprises about
80%
 Squamous cell carcinoma (SCC) 20% of NMSC

 Exposure to ultraviolet solar radiation, especially
ultraviolet B
 Painful sunburn before age 20 is related to later
development of premalignant lesions as well as
NMSC and melanoma
 Cumulative lifetime sun exposure is related to
increased risk of SCC and BCC.

Host risk factors
blonde or red hair, fair complexion, blue
eyes, and tendency to burn rather than tan

 Genetic predisposition
 xeroderma pigmentosum
 basal cell nevus (Gorlin's) syndrome
 epidermodysplasia verruciformis
 Muir-Torre syndrome
 Porokeratosis
 Bazex syndrome
 Rombo syndrome
 Albinism
 phenylketonuria.

 Infections- An association exists between
cutaneous SCC and human papillomavirus
 Immunosuppression- Transplant recipients on
immunosuppressive therapy
 AIDS , multiple myeloma, leukemia, and
lymphoma also are at increased risk

 more frequent and aggressive in areas of chronic
skin damage
 ulcers, osteomyelitis, sinus tracts and burn
(Marjolin's ulcer), or vaccination scars.
 Areas of chronic skin inflammation
 discoid lupus erythematosus, lichen sclerosus,
lichen planus, dystrophic epidermolysis bullosa,
and lupus vulgaris

 IONIZING RADIATION
 Exposure to ionizing radiation is a risk factor for
both BCC and SCC
 especially in those people with sun-sensitive
phenotype and younger age at exposure
 risk is directly related to cumulative radiation
dose
 Increased incidence of NMSC also occurs with
chronic radiation dermatitis following therapeutic
radiation.

 Chemical skin cancer carcinogens
 Arsenic (herbicide, pesticide ), soot, and
polycyclic aromatic hydrocarbons from coal tar,
cutting oils
 An association exists between cigarette or pipe
smoking and cutaneous SCC

 Actinic (Solar) Keratoses-
 Actinic keratoses tend to be multiple.
 AKs are red, pink, or brown papules with a scaly
to hyperkeratotic surface
 They occur on sun-exposed areas and are
especially common on the balding scalp,
forehead, face, and dorsal hands

 Malignant transformation to SCC occurs in about
1% of lesions
 with cumulative lifetime risk 6% to 10%
depending on number and length of time lesions
are present

 Treatment
 Excision
 Cryotherapy
 desiccation and curettage
 Dermabrasion
 topical therapy with 5-FU or imiquomod
 laser resurfacing.

Bowen's Disease
 typically appears as a reddish-brown
 scaly patch or thin plaque on the sun-exposed
head, neck, extremities, or trunk of an older
individual
 On histopathologic evaluation demonstrates full-
thickness epidermal atypia, with more
pronounced nuclear polymorphism and
apoptosis

 Other features include confluent parakeratosis,
and, not infrequently, the adnexal extension of
neoplastic cells
 It may arise from a pre-existing actinic keratosis
or de novo.
 Progression to invasive SCC occurs in 5% to
20% of cases

 TREATMENT
 Surgical excision is usually preferred
 radiation therapy may be considered as an
alternative.
 45 to 50 Gy at 2.5 to 3.5 Gy per fraction
 Facial lesions require 56 Gy at 2.0 Gy per
fraction for improved cosmesis

Keratoacanthoma
 benign, self-healing lesions
 presents as a rapidly enlarging papule that
becomes a crateriform nodule with a central
keratinous plug over a period of weeks to
months.
 have the potential to destroy large volumes of
tissue and may be associated with SCC

 Lesions can be treated with radiation
 Doses of 35 Gy in 12 to 14 fractions or 45 Gy in
15 to 20 fractions have been used

 Lentigo Maligna and nevi are precursors of
melanoma

 a neoplasm of keratinizing cells that shows
malignant characteristics
 Anaplasia
 rapid growth
 local invasion
 metastatic potential

 Invasive tumor lobules push downward from the
overlying epidermis and detached tumor islands
are noted within the dermis
 Both cytoplasmic and cystic keratinization may
be observed.
 The degree of keratinocyte differentiation within
these tumors is variable and an important
prognostic factor.

 Verrucous carcinoma
 is an indolent, well-differentiated squamous cell
carcinoma
 grows slowly as an exophytic, cauliflower-like
lesion
 may be associated with human papilloma virus
infection

 This may arise in the anogenital region
(Buschke-Lowenstein tumor)
 oral cavity (oral florid papillomatosis)
 on the plantar surface of the foot (epithelioma
cuniculatum)

 Spindle cell carcinoma
 a rare subtype of squamous cell carcinoma
 usually develops in sun-exposed areas in lightly-
pigmented individuals older than 40 years of
age.
 The prognosis primarily depends on the depth of
invasion
 Verrucous and spindle cell carcinomas are
managed similar to more conventional
squamous cell carcinomas.

 subtypes associated with clinically aggressive
behavior
 adenoid (pseudoglandular)
 Acantholytic
 Adenosquamous
 desmoplastic squamous cell carcinoma.

 A careful history
 should include questions regarding patient risk
factors
 personal and family history of skin cancer
 UV exposure history,
 history of ionizing radiation therapy
 occupational exposures
 immunosuppression

 Slowly enlarging growth on or just beneath the
skin surface
 History of sore that will not completely heal
 Bleeding or pain unusual
 Paresthesia and formication in case of perineural
spread (3-14%)

 Site, size, mobility of the primary lesion should
be documented
 Evidence of PNI is assessed
 Any features of cartilage or bone invasion should
be examined
 Complete skin examination should be done
 Regional lymph nodes

 Typical lesions are round-to-irregular, plaquelike
 nodular, and overlaid with a warty keratotic
scale or conical keratinized cutaneous horn.
 Surrounding erythema may be present, and
bleeding results from minimal trauma
 usually superficial, invasion of the subcutis does
occur with muscle invasion and extension along
periosteal, perineural, and angiolymphatic
channels.

 Biopsy should be performed before deciding on
treatment
 Small lesion occurring on free skin areas ( not
involving eye lid, ear or periorbital areas ) can
undergo biopsy and simultaneous excision
 Larger lesion or those involving areas where
cosmetic or functional deficit will occur with
excision
 Incisional biopsy or punch biopsy

 Biopsy should include deep reticular dermis
 This is preferred because infiltrative pathology
may be found only in deep tissues
 Superficial biopsy will frequently miss this

 Done in extensive disease such as
 bone involvement
 PNI
 deep soft tissue involvement
 lymphovascular invasion is suspected

 In the case of carcinomas involving the medial or
lateral canthi of the eyes
 one should consider obtaining either a (CT) or
(MRI) scanto assess the depth of invasion
 because apparently superficial cancers
sometimes extend along the wall of the orbit

CT Scan is done to role out bone and cartilage
invasion
 Lymph node status can also be assessed
MRI preferred over CT when PNI is suspected

 Clinically or radiologically if lymph node present
 Proceed with fnac
 If negative repeat fnac or excision biopsy of node

 SURGERY
 RADIOTHERAPY
 offer equivalent excellent cure rates of 90% to
95%
 treatment approach must be individualized
based on specific risk factors and patient
characteristics for the most acceptable cosmetic
and functional outcome.

 The management of skin cancer is guided by the
biologic and histologic nature of the tumor, the
anatomic site, the underlying medical status of
the patient
 It is desirable to avoid RT in young patients
 Late effect of RT progress with time

 Localized scc are most commonly treated with
surgery
 Curettage with electrodesiccation is the
alternatively scraping away the tumor tissue with
a curette down to a firm layer of normal dermis
and denaturing the area with electrodessication
 It is fast and cost effective
 Margin cannot be assessed

 Curettage with electrodesiccation reserved for
 actinic keratoses (AKs), and SCC in situ without
follicular involvement located on the trunk or
extremities
 but are contraindicated in deeply infiltrating lesions
 Wound contracture may cause tissue distortion and
impaired cosmesis
 Cure rate is about 90-95% for low risk tumors
 Recurrence rate high about 20-25% for high risk
features

 EXCISION WITH POST OP MARGIN
ASSESSMENT (POMA)
 Standard surgical excision followed by post op
pathological evaluation of margins
 For low risk tumors < 2 cm – 4-6mm margin
 For high risk tumors higher margins are required

 Mohs surgery or excision with intra operative
frozen section assessment
 Preferred technique for high risk scc

 Mohs' micrographic surgery
 involves fixation of tumor to enable tumor
mapping and surgical excision with multiple
frozen sections taken until microscopically clear.
 Cosmesis, often poor just after the procedure,
improves with time.

 A key defining feature of MMS is that the
surgeon excises, maps, and reviews the
specimen personally, minimizing the chance of
error in tissue interpretation and orientation
 This technique is employed for BCC and SCC in
embryonic fusion zones
 recurrent or deeply invasive lesions
 tumors with potential for diffuse lateral spread or
perineural invasion

 Although surgery is main treatment for nmsc
 Patient preference and other factor may lead to
choice of RT
 early skin cancer of eyelid, external ear ,or nose
may result in significant cosmetic deformity and
necessitates complex reconstructions

 Elderly patients who are not fit for surgery
 Patients with PNI with gross tumor extending to
the sites which makes lesion unresectable
 Such lesions are treated with RT alone

 positive surgical margins
 perineural invasion
 invasion of bone, cartilage, and skeletal muscle

 Cure rates lower
 Reserved where surgery or radiotherapy is
contraindicated or impractical
 Cryotherapy , topical 5 FU, imiquimod, Photo
dynamic therapy

 immune-response modifier that promotes a cell-
mediated immune response
 through induction of cytokine production,
particularly interferon @ and b and interleukin-
12.
 treatment of Aks, scc insitu and superficial BCCs
on the trunk, neck, or extremities

 PDT involves application of photo sensitizing
agent on skin followed by irradiation with light
source
 Used for premalignant or low risk superficial on
face and scalp

 exposes skin cancers to destructive subzero
temperatures.
 Heat transfer occurs from the skin, which acts as a
heat sink.
 Tissue damage is caused by direct effects initially
 subsequently by vascular stasis, ice crystal
formation, cell membrane disruption, pH changes,
hypertonic damage, and thermal shock

 inability to evaluate thoroughness of tumor
eradication.
 The absence of margin
control
 development of dense scar, which might obscure
recurrence

 Involvement increase the chance of recurrence
and mortality
 Associated with PNI, LVI, poor differentiation

 Lymph node dissection followed by adjuvant RT
 Cervical node
 Neck dissection alone if only one involved
 If 2 or more or ECE neck dissection followed by
RT

 Metastatic to parotid node is common if cervical
lymph nodes are involved (60-80%)
 Superficial or total parotidectomy followed by RT
 If inoperable parotid node – high dose preop RT
60-70 Gy followed by parotidectomy
 20 % decrease in local recurrence with addition
of RT
 5 YR survival also increased by 15-20%

 EBRT
 Ortho voltage x rays
 Electron beam
 High energy x rays
 OR
 INTERSTITIAL IMPLANT

 100- 250 Kvp
 Most early skin cancer can be treated
 Advantages
 Maximum dose at skin surface, no bolus
required
 Less beam constriction both at surface and at
deapth so smaller field can be used
 Shielding of eye is easier

 DISADVANTAGES
 Higher dose to deeper tissues and to underlying
bone and cartilage
 It is unavailable in most RT Dept.

 It is usually used for treatment of scalp lesion
inorder to reduce dose to brain
 If tumor is located near eye – gold plated lead
eye shield is directly placed over anaesthetised
cornea

 Advanced skin cancer that are deeply invasive
are often treated with higher energy
 To adequately cover the deeper tissue
 Bolus is kept to ensure the adequate surface
dose
 Field arrangement may vary depending on sites

 Wedge pair technique – external ear
 3 field technique- lesion extending along 5 th
nerve
 Even IMRT can be used when we have to treat
till base of skull in case of PN

 Proper immobilization to ensure consistent
delivery of treatment is essential
 primary skin collimation with custom lead cutouts
can also be used to define the field in case of
electrons
 To minimize normal-tissue toxicity, underlying
structures such as the lens, cornea, nasal
septum, and teeth should be protected by
placing a lead shield under the eyelids over or in
the nasal cavity or under the lips

 The margin of normal-feeling tissue included in
the target volume is usually 0.5 to 1.0 cm for skin
cancers of 2.0 cm
 1.5 to 2.0 cm for larger cancers.
 At least a 0.5-cm margin on the suspected depth
of invasion should be included in the target
volume
 Wider margin while using electrons

 Sequelae of Radiation Therapy
 Moist desquamation
 The skin in the radiation field may gradually
become telangiectatic, atrophic, and
hypopigmented over a period of years and is
more sensitive to trauma.
 healing may be delayed after surgery on an
irradiated region.
 Hair loss and a loss of sweat gland function are
usually permanent

 Ectropion and epiphora may develop after the
treatment of eyelid carcinomas (particularly ones
involving the lower eyelid)
 The incidence of soft tissue necrosis is typically
less than 3%.
 Osteoradionecrosis occurs in approximately 1%
of patients
 radiochondritis is rare

 3-4 % of scc can have distant metastases
 Systemic chemotherapy
 Platinum based chemotherapy
 Interferon @ or cis- retinoic acid
 Cetuximab and gefitinib is also tried

Squamous cell carcinoma skin

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