ÁREA DE EJECUCIÓN:
6 REGIONAL CENTRO Y EJE NEOVOLCÁNICO
• It is mesodermal in origin.
• It is mostly seen during first and second decades.
• It usually grows rapidly and spreads by blood stream.
• It is generally painless and confused with benign conditions like hematoma. Diagnosis is often delayed.
• On clinical examination it appears as a fleshy mass (Sarx:Flesh). Dilated veins may be seen in overlying skin. The consistency is variable depending upon
Fig. 11.11: Rhabdomyosarcoma of chest wall amount of fibrous tissue and vascular tissue present
in it. On palpation, tumor is warm and pulsatile due to high vascularity. Types of sarcoma are shown in Box 11.12A.
Box 11.12A: Types of sarcoma
Cell of origin Sarcoma
Fat cells Liposarcoma
Fibroblasts Fibrosarcoma
Osteoblasts Osteosarcoma
Chondroblasts Chondrosarcoma Striated muscles Rhabdomyosarcoma
(Fig. 11.11) Smooth muscles Leiomyosarcoma
Blood vessels Hemangiosarcoma
Lymph vessels Lymphangiosarcoma
Nerves Neurofibrosarcoma
• Treatment is wide excision with surrounding healthy tissue (2-3 cm) to prevent recurrence. Incomplete excision has high recurrence rate (Fig. 11.12A).
Other treatment modalities are radiotherapy and chemotherapy.
• Salient features of sarcoma are summarized in Box 11.12B.
Box 11.12B: Sarcoma—salient features
Age Children Rhabdomyosarcoma
20-40 years Kaposi’s sarcoma, synovial sarcoma,osteosarcoma Elderly Angiosarcoma, fibrosarcoma
History Painless, rapidly growing soft tissue tumor
Location Head and neck Angiosarcoma, osteosarcoma Retroperitoneum Liposarcoma
Extremities Liposarcoma, osteosarcoma, synovial sarcoma Inspection Diffuse swelling, dilated veins in overlying skin
Palpation Nontender, warm, variable consistency, may be pulsatile
Regional lymph nodes Usually not enlarged. May be enlarged in rhabdomyosarcoma, malignant fibrous histiocytoma, synovial sarcoma
Systemic Examination (For metastasis):
Liver enlarged, non-tender Lung findings
Bony tenderness
Investigations FNAC/Wedge biopsy (to confirm diagnosis) MRI of affected part (to assess the extent) X-ray chest, USG abdomen (metastatic work up)
Treatment Wide excision
Compartment excision Amputation
RT/CT
• Comparison between carcinoma and sarcoma is shown in Box 11.13.
Basal Cell Carcinoma (Rodent ulcer)
• It is most common malignant skin tumor (Box 11.14A).
• It is a tumor of low grade malignancy. Mortality is extremely rare but cosmetic disfigurement is the main consideration with basal cell carcinoma.
• It commonly affects white skinned people of elderly age having high exposure to sunlight (in Australia, New Zealand).
• Site: It is mostly seen on face above an arbitrary line joining ear lobule to the angle of mouth (sun exposed area). The commonest site is inner canthus of eye.
• It is also called ‘tear cancer’ because it is commonly seen in region of the face where tears roll down.
• Types:
i. Nodular: Solid, non-fluctuant swelling with central depression and pearly appearance.
ii. Cystic: Blue-gray, semitranslucent, cystic nodule with a network of fiery red blood vessels on the surface.
iii. Ulcerative: Non-healing ulcer is the commonest presentation. Temporary healing occurs with crusting. But the crust breaks down with a sero-hemorrhagic discharge leading to recurrent ulceration. On examination, the margins of ulcer are raised and rolled out (like a motor car tyre) with central ulceration covered with scab.
iv. Field fire type: It grows rapidly leading to destruction and disfigurement of facial skin. It has irregular spreading edge with central scarring (Fig. 11.13).
• Spread: The tumor is slow growing and locally invasive, hence called Rodent ulcer. It gradually Fig. 11.12: Recurrent fibrosarcoma after
incomplete excision
• It arises from basal cells of pilosebaceous adnexa and occurs only in skin.
• It cannot occur in the mucosal surface having squamous epithelium (tongue, lips) due to lack of pilosebaceous adnexa in these areas.
Box 11.13: Comparison between carcinoma and sarcoma
Carcinoma Sarcoma
Origin: Ectodermal or Mesodermal Endodermal
Age: Middle or elderly age Young age
Occurrence: Very common Less common tumor tumor
Progress: Slow growing Rapidly growing tumor tumor
Metastasis: Lymphatic Blood-borne metastasis metastasis common and is common and occurs occurs early. Blood-borne early. Lymphatic metastasis metastasis occurs late is rare.
Treatment: Surgery is main Surgery is main treatment treatment. Mostly radio- Mostly radioresistant.
sensitive
Box 11.14A: Malignant skin tumors
• Low grade tumors
• Diagnosed early due to their location
• Good prognosis
• Distribution
70% Basal cell carcinoma 20% Squamous cell carcinoma
5% Malignant melanoma
Fig. 11.13: Rapidly spreading basal cell carcinoma causing facial disfigurement
erodes deeper tissues like muscles, bone, cartilage, etc. and produces severe disfigurement.
Spread by lymphatics or bloodstream does not occur.
Rarely basal cell carcinoma changes to squamous cell carcinoma in recurrent or neglected cases. In such situation, margins of the ulcer become everted and it spreads to regional lymph nodes.
• Differential diagnosis: See Box 11.14B.
• Treatment: Surgery and Radiotherapy are equally effective. The type of treatment is decided by the patient’s condition and extent of disease.
In patients having extensive tumor eroding skull bones, radiotherapy is the treatment of choice.
Dosage of radiotherapy is 4000-6000 rads.
In patients having localized lesion of the face, surgery is the treatment of choice (Box 11.14C).
Tumor is excised with a healthy margin (3-5 mm).
If the defect is small, it can be closed primarily. If the defect cannot be closed primarily, it should be covered with split or full thickness skin graft.
On face, full thickness graft is taken from post-auricular skin and it gives better cosmetic result.
Larger defect requires plastic reconstruction using pedicle flap.
Moh’s micrographic surgery: This is a specialized dermatological technique meant to minimize tissue damage and to decrease disfigurement on areas like face. Visible tumor is excised in horizontal slices. The completeness of excision is confirmed by taking frozen sections from undersurface of excised lesion.
Cryosurgery and CO2 laser can be used for treating small lesions.
Measures to prevent basal cell carcinoma include wearing protective clothing and sunscreen to prevent UV damage during sun exposure.
Squamous Cell Carcinoma
(Epithelioma, Epidermoid Carcinoma)
It arises from surfaces covered with squamous epithe-lium (skin, upper aerodigestive track, vagina).
Sometimes surfaces not covered by squamous epithe-lium undergo a change to squamous type due to factors causing chronic irritation (squamous metaplasia), e.g.
• Transitional cell lining of urinary bladder undergoes squamous metaplasia by stones.
• Columnar cell lining of gallbladder undergoes squamous metaplasia due to gallstones.
In case of skin, squamous cell carcinoma arises from prickle cell layer of epidermis.
It is more common in skin of the face of elderly people.
It is more common in white skinned people.
It is more malignant and more rapidly growing than basal cell carcinoma. The differences between squamous and basal cell carcinoma are shown in Box 11.17C.
Premalignant skin lesions that can develop to squamous cell carcinoma are shown in Box 11.15.
Types
• Ulcerative— commonest presentation
• Proliferative—cauliflower like
• Ulceroproliferative Clinical Features
• It commonly presents as non-healing ulcer that is progressively increasing in size.
• The ulcer is irregular in shape with everted and indurated edges. The base is indurated, attached to deeper structures and has a blood stained discharge (Figs 11.14 and 11.15).
Box 11.14C: Surgical management—basal cell carcinoma and squamous cell carcinoma
Box 11.14B: Basal cell carcinoma—
differential diagnosis
• Squamous cell carcinoma—everted margins
• Malignant melanoma—mimics pigmented basal cell carcinoma
• Keratoacanthoma—presents on face with ulceration and raised margins
• Sclerosing angioma
• The diagnosis is confirmed by wedge biopsy from the margin of the ulcer that shows ‘epithelial pearls’
or ‘cell nests’.
Spread
• Local spread to adjoining structures.
• Lymphatic spread to regional lymph nodes.
• Blood spread occurs only in very advanced stage.
Differential diagnosis: See Box 11.17A.
Treatment (Box 11.17B) Treatment of primary lesion:
• Surgery and radiotherapy are equally effective.
• Principles of local treatment are same as for basal cell carcinoma (see Box 11.14C).
Box 11.15: Premalignant skin lesions
• Leukoplakia: Small, circumscribed white plaque
• Senile (solar) keratosis: Prolonged sun exposure
• Paget’s disease
• Bowen’s disease: Well-defined brownish induration of skin
• Radiodermatitis: Exposure to X-rays
• Lupus vulgaris: Cutaneous tuberculosis
• Chronic ulcers (Marjolin’s ulcer) (Box 11.16): Venous ulcer, keloid
• Xeroderma pigmentosa
• Conditions causing chronic skin irritation:
Countryman’s lip is carcinoma lower lip in farmers due to sun exposure.
Chimney sweep cancer is carcinoma scrotum in chimney sweepers due to irritation by clothes soaked in oil or pitch.
Kangri cancer is carcinoma of abdominal wall due to Kangri (charcoal burner) applied by Kashmiris to abdominal wall for protection against cold.
Kang cancer is carcinoma of buttocks, heels and elbows due to sleeping on oven bed by Tibetans.
Fig. 11.14: Fungating, cauliflower like growth in the neck—squamous cell carcinoma
Fig. 11.15: Fungating growth involving sole—
squamous cell carcinoma
Box 11.17A: Squamous cell carcinoma—
differential diagnosis
• Basal cell carcinoma
• Tubercular ulcer
• Syphilitic ulcer
• Chronic nonspecific ulcer
• Granuloma pyogenicum
• Keratoacanthoma Box 11.16: Marjolin’s ulcer
• Carcinoma developing in long standing ulcer/scar
• Slow growing (because it is avascular)
• Painless (because it has no nerves)
• No metastasis to regional lymph nodes (because it has no lymphatics)
• If it invades adjoining skin, it starts behaving as squamous cell carcinoma
• Treatment: Wide excision.
• It is radioresistant (because of avascularity)
Box 11.17B: Outlines of treatment—squamous cell carcinoma
• Tumor should be excised with healthy margin of 1-2 cm.
• Chemotherapy is also useful in advanced cases.
Box 11.17C: Comparison between squamous and basal cell carcinoma
Squamous cell carcinoma Basal cell carcinoma
Incidence Less common than basal cell carcinoma Commonest skin malignancy Origin Prickle cell layer of epidermis Basal cell layer of epidermis
Etiology Chronic irritation UV rays
Site Any part of skin. Internal organs like Mostly on sun exposed area of face gallbladder, urinary bladder (due to
squamous metaplasia)
Tumor grade High grade tumor, grows rapidly Low grade tumor, grows slowly Clinical findings Irregular ulcer with everted edges Rounded ulcer with raised and rolled
out edges.
Histopathological findings Solid columns of epithelial cells growing down Basaloid appearance of epithelial into the dermis. Presence of ‘epithelial islands.
pearls’ or ‘cell nests’.
Spread Locally invasive, spread to regional lymph Locally invasive, does not spread by
nodes common. lymphatic or hematogenous route.
Treatment Surgery and RT. Involved lymph nodes need Surgery/RT. Regional lymph
block dissection. nodes do not need any treatment
since they are not involved
Treatment of metastatic lymph nodes:
• The regional lymph node enlargement can be due to secondary infection of the ulcerated growth. In
such case, the decision for surgery should be taken only if lymph nodes do not regress with antibiotic treatment.
• Diagnosis of metastatic deposits in lymph nodes is confirmed by FNAB.
• The treatment is block dissection of regional lymph nodes.
• If lymph nodes are large and fixed, palliative RT should be given.
Malignant Melanoma
It is a malignant tumor arising from melanocytes.
Malignant melanoma of skin is regarded as carcinoma (Melanocarcinoma). It has very high rate of metastasis.
Origin: It may arise de novo in normal skin or malignant change may occur in a pre-existing mole (Box 11.18).
Predisposing factors: Shown in Box 11.19.
Box 11.18: Features of malignant change in pre-existing mole
• Increase in size of mole
• Pigmentation becomes deep
• A halo of pigmentation appears in surrounding skin
• Itching
• Ulceration
• Bleeding
• Scab formation
• Enlargement of draining lymph nodes
Box 11.19: Predisposing factors for malignant melanoma
• UV rays
• White race
• Age: After puberty
• Sex: More in females
• Genetic predisposition
• Trauma
• Pre-existing mole
Site
Common sites: ‘BANS’ area (Back, Arms, Neck and Scalp), lower legs in females.
Rare sites: Eyes, meninges, anal canal.
Classification
i. Lentigo maligna melanoma:
• It is malignant change occurring in Hutchinson’s melanotic freckles.
• Malignant change occurs in 10 years or more.
• It is seen in 6-8th decade.
• Relatively less aggressive.
• It appears on parts exposed to sun.
ii. Superficial spreading melanoma:
• Most common but less aggressive lesion.
• It can occur anywhere but more common on exposed parts of the body.
• Intradermal spread of tumor occurs in radial (Horizontal) direction.
• It presents as a flat, irregular pigmentation of skin (Fig.11.16).
iii. Nodular melanoma:
• Less common but more malignant.
• It can occur anywhere but mostly seen in genital and anal region.
• It mainly grows vertically and there is little radial growth.
• It presents as small, circumscribed, pigmented nodule that itches, ulcerates and bleeds (Fig. 11.17).
• Metastasis occurs early.
iv. Acral lentigenous melanoma: It is commonly seen on palm, sole and under the nail (subungual melanoma). Subungual melanoma begins as an area of pigmentation in the nailbed. The Fig. 11.16: Superficial spreading melanoma involving sole
Box 11.20: Comparison of classification methods Clark’s level of Breslow’s tumor Prognosis
invasion thickness
Level-I 0.75 mm Low-risk group. Do
not metastasize Level II 0.76-1.5 mm Intermediate risk
group
Level-III Metastasis in 25%
cases
Level-IV >1.5 mm High-risk group.
Level-V Metastasis in 60%
cases pigmentation increases and raises the nailbed. The
tumor may extrude through nail plate leading to ulceration and bleeding.
v. Amelanotic melanoma: Usually malignant mela-noma is a pigmented lesion but sometimes it has no or very little pigment, hence called amelanotic melanoma. It carries poor prognosis due to delay in the diagnosis. The cases usually present with regional lymph node metastasis.
CASE SUMMARY
50 years male presented with painless enlargement of left groin nodes for one year. There was no response to antibiotics and FNAC done twice was inconclusive. On careful examination of left lower limb, a painless, pigmented lesion was seen involving left sole that turned out to be malignant melanoma (Fig. 11.16). The enlarged groin lymph nodes were due to metastatic deposits. The patient underwent amputation foot with block dissection of groin nodes.
Learning Point: In case of lymphadenopathy, always examine the drainage area carefully.
Staging
Staging is done for planning treatment and to assess prognosis. Various methods of staging are:
1. Clinical staging: It is the simplest method.
Stage-I Primary tumor only
Stage-II Enlargement of regional lymph nodes Stage-III Distant metastasis to lungs, liver, brain,
bones, etc.
2. Clark’s level of tumor invasion: This staging is done after histopathological examination of excised tumor specimen (Fig. 11.18).
Level-I Tumor cells in epidermis above base-ment membrane.
Level-II Tumor invading papillary dermis.
Level-III Tumor at junction of papillary and reticular dermis.
Level-IV Tumor invading reticular dermis.
Level-V Tumor invading subcutaneous fat.
3. Breslow’s thickness of lesion: Staging is done by measuring the maximum vertical thickness of melanoma at its center using optical micrometer.
Stage-I Thickness 0.75 mm or less Stage-II 0.76 to 1.5 mm
Stage-III 1.51 to 3.0 mm Stage-IV More than 3.0 mm
Breslow’s tumor thickness is considered to be more practical and reliable indicator of prognosis than level of invasion. However, it is difficult to apply in ulcerated lesion. Its comparison with Clark’s level of invasion is shown in Box 11.20.
Fig. 11.17: Nodular melanoma neck
Fig. 11.18: Clark’s level of tumor invasion
Spread
i. Local extension.
ii. Lymphatic spread: It occurs to regional lymph nodes by embolization. In case of lymphatic spread by permeation, ‘satellite nodules’ appear between primary tumor and regional lymph nodes.
iii. Hematogenous spread: It occurs to liver, lungs, brain, bones and skin.
Prognostic factors: Shown in Box 11.21.
Box 11.21: Prognostic factors
• Poor prognosis seen in:
— Male sex
— Black race
— Primary lesion of head and neck
— Advanced clinical stage
— Ulceration
— Satellite nodules
— Tumor thickness >1.5 mm
— High level of invasion (level IV and V)
Clinical Examination
• Pigmented skin lesion, usually black in color.
• The size is variable and margins are usually irregular.
• Surface may be flat or raised above the skin (nodular).
• There may be ulceration in the center covered by crust.
• Consistency is firm.
• Mobility: The tumor arises from skin and can be lifted from deeper structures.
• Surrounding skin: There may be a pigmented halo around the primary lesion and ‘satellite nodules’ may be seen.
• Regional lymph nodes may be enlarged.
• There may be hepatomegaly (liver metastasis), pleural effusion (lung metastasis), neurological deficit (brain metastasis) and pathological fracture of long bones (bony metastasis).
Differential diagnosis: See Box 11.22.
Investigations
• Diagnosis is confirmed only by excision biopsy. Other investigations are done based on suspicion of metastasis.
• Lymphangiography to look for lymph node metastasis. It is technically difficult and gives high false positive or negative results, hence not used commonly.
• FNAC of enlarged regional lymph nodes is very accurate in picking up metastasis. Open biopsy of lymph node should be avoided to prevent tumor spillage.
• Ultrasound abdomen for liver metastasis.
• Chest X-ray for pulmonary metastasis (canon ball shadow, pleural effusion).
• CT/MRI head for brain metastasis.
• Bone scan for bony metastasis.
Treatment
Treatment of Primary Lesion (Stage-I):
Surgical excision is the treatment of choice. There is no role of RT or CT as it is resistant to both. The surgical excision should include 1-2 cm of adjoining healthy skin. The depth of excision should not go beyond deep fascia since it limits the local recurrence.
The excision should be elliptical in shape (along line of Langer) to allow tension free closure. The residual defect is closed primarily or with skin graft or with flap reconstruction.
Subungual melanoma is treated by amputation of the digit.
Melanoma of sole of the foot is treated by wide excision/amputation.
Treatment of Regional Lymph Nodes (Stage-II):
Clinically involved lymph nodes require block dissection.
If lymph nodes are situated near the primary lesion, block dissection is done ‘in continuity’ with excision of primary tumor so as to remove ‘in transit’ deposits. If lymph nodes are far away from primary lesion, then two areas are removed through separate incisions. If lymph
Box 11.22: Differential diagnosis of malignant melanoma
• Pigmented basal cell carcinoma
• Cafe-au-lait spots
• Cavernous hemangioma
• Pigmented senile warts
• Blue nevus
• Kaposi’s sarcoma
• Peutz-Jegher’s syndrome: Familial condition. There is circumoral pigmentation with multiple intestinal polyps.
nodes are fixed and inoperable, then palliative radiotherapy is given.
Treatment of Metastatic Malignant Melanoma (Stage–III):
Aim of treatment is palliation only.
i. Radiotherapy for cerebral and bony metastasis ii. Chemotherapy: Drugs used are DTIC, vincristine,
cisplatin.
iii. Immunotherapy: Using BCG, Levamisol, Inter-ferons, monoclonal antibodies.
Spontaneous regression is sometimes known to occur in malignant melanoma due to development of antibodies by body’s natural defense mechanism.
Glandular Carcinoma It arises from endoderm.
It arises from sites containing glandular tissue, e.g.
breast, thyroid, alimentary tract, etc. Its types are:
i. Carcinoma simplex: Cells are arranged in circumscribed groups and glandular structure is not identified, e.g. carcinoma breast.
ii. Adenocarcinoma: Cells are arranged in form of acini and resemble with gland of their origin, e.g.
intestinal adenocarcinoma.
iii. Colloid (mucoid) carcinoma: It arises from mucin secreting cells. The mucin permeates the stroma and gives gelatinous appearance, e.g. carcinoma colon.
Lymphoma
See Chapter 13: Diseases of Lymphatic System and Lymph Nodes.