Topics discussed in this Tutorial
Tumours around Joints
Adnexal tumours around the eyes
Muscle tumours
Follicular Tumours
Lymphangioma circumscriptum
Cutaneous Fibrosarcomas
Juvenile fibromatoses
DD of Cysts
DD of Lipomas
Vascular tumours
The Differential Diagnosis of Tumours Around Joints
Consider them in terms of arthroses, infections, granulomas, immune disorders, infiltrates and tumours. The arthroses are gout, rheumatoid, relapsing polychondritis and ganglion. The infections are milkers nodule, orf, cowpox and syphilis. The granulomas are sarcoid, granuloma annulare, leprosy and reticulohistiocytomas. The immune conditions are things like lupus, erythema elevatum diutinum, dermatomyositis and Behcet’s syndrome. The infiltrates are cells, knuckle pads, calcium and xanthoma and the tumours are Maffucci’s, warts and corns.
The image below is of Rheumatoid nodules
Maffucci's syndrome
Adnexal Tumours Around the Eyes
Syringomas, eccrine hidrocystomas, apocrine hidrocystomas and eccrine hidradenoma.
The image below is a hydrocystoma courtesy of Dr Nameer AlSudany
Muscle Tumours
The benign ones are leiomyomas, angioleiomyoma, a dartos leiomyoma and a standard skin leiomyoma. Malignant ones are leiomyosarcomas and granular cell myoblastomas.
The image below is of multiple leiomyomas courtesy of Dr Nameer AlSudany
Follicular Tumours These include inverted follicular keratoses particularly seen on the nose, trichoepithelioma, multiple eruptive milia, trichofolliculoma which has a central punctum like a BCC, trichilemmoma, trichodiscoma and pilomatrixoma.
 The Osteomas The osteomas if they occur in syndromal form are seen in Gardner’s syndrome. You may have multiple osteomas on the forehead or numerous miliary osteomas on the cheeks. Pilomatrixomas, osteomas and cutaneous calculus are all very hard.
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Lymphangioma Circumscriptum The base colour can be red but you always have some small vesicle like lesions. They can be clear or have blood in them. They can also be dark. The image below is lymphangioma circumscriptum  Penile pigmentation Note also a fixed drug or erythema multiforme on the penis. There is always pigmentation and blistering indicating chronicity.
The slide looking like brown measles is urticaria pigmentosa
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These are ivory white perifollicular papules in patches often of wide extent affecting the chest and back. Sometimes they are linear.
Juvenile Fibromatoses
First of all there is congenital generalised fibromatosis or aggressive infantile fibromatosis. Internal organs are affected and it may be fatal. Juvenile palmoplantar fibromatosis occurs at birth up to adolescence. There are nodules over the thenar or mid sole. There is rapid growth and x-ray shows fine calcification. Infantile digital fibromatosis is on the dorsum of the fingers and toes. They can be single or multiple usually on the extensor aspects of the terminal phalanx and tend to go by the age of three so it is important that these will go on their own. Fourthly there is fibromatosis colli. This is otherwise known as a sternomastoid tumour. Fifthly Hereditary camptodactyly. This presents as childhood Dupuytren’s usually involving the fifth finger. This may be part of Marfan’s syndrome.
The Poly Fibromatosis Syndromes
These include Dupuytren’s, contracture, knuckle pads, plantar fibromatosis, keloid scarring and periarticular arthritis of the shoulder and sometimes plastic induration of the penis.
The Differential Diagnosis of Skin Cysts
These can be keratinous, adnexal, branchial or thyroglossal. The keratinous ones are tricholemmal or pilar cysts that have no granular layer, epidermoid and milia, the latter having a granular layer. Adnexal cysts are eccrine hidrocystoma and apocrine hidrocystoma. Branchial cysts are anterior to the sternomastoid muscle and can be single or multiple. Thyroglossal, Bartholin’s, dermoid, myxoid and steatocystoma multiplex and also eruptive vellus hair cysts that presents as brown papules on the chest are other variants.
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| Dermoid cyst |
The Differential Diagnosis of the Histiocytoses
These are juvenile xanthogranuloma, benign cephalic histiocytosis and self- healing histiocytosis.
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| Juvenile xanthogranuloma |
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| Benign cephalic histiocytosis |
The Differential Diagnosis of Lipomas
There are simple lipomas, there is multiple lipomatosis which is usually in males on the extremities with diffuse infiltration with mature fat. There are angiolipomas that are painful and also often multiple and have a bluish look. There is Dercum’s disease with a slow onset usually in a female and circumscribed diffuse painful plaques, particularly on the thighs. There are hibernomas that are generally made up of brown fat and there is benign lipo blastomatosis that is circumscribed and diffuse form with upper and lower limbs being involved in children over the age of three.
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| Madelung disease symmetric lipomatosis |
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| Dercum's disease |
Dermal Tumours
As a generalisation dermal nodules are granulomas, infiltrates with cells and substances or bacteria, tumours or vasculitis. The tumours are histiocytic, fibrositic, lipomas, cysts, angiomas, myxomas and adnexal.
Some General Comments
Cylindromas are pink and smooth and look like BCCs. They are usually seen around the scalp margin.
Fibrous epithelioma of Pinkus is sessile. It looks like a non-pigmented seborrhoeic keratosis or a BCC.
Spitz nevus usually has a reddish tinge to it but the colours can vary from bright red to dark brown.
Dermatofibrosarcoma protuberans is often in the flexures of the abdomen and is lobulated. Note that lobulation feature.
A glomus tumour on the back of the hand often has a dull purple swelling.
A Juxta articular fibroma is a swelling on the dorsum of the finger that can look like granuloma annulare.
If you have a foot with a rugose sole and big fourth and fifth toes, consider juvenile plantar fibromatosis but also think of a plexiform neuroma or the Proteus syndrome.
An eccrine poroma on the sole makes you look for the little collarette at the edge and it is usually smooth rather than verrucous.
Eccrine spiradenoma is painful and solitary.
Blue Rubber Bleb Nevus Syndrome Versus Glomangioma
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| Blue rubber bleb nevus |
The differential diagnosis if multiple include tricholemmal cysts. If they are small and few then consider a trichoepithelioma and steatocystoma multiplex or solitary BCC. Cylindromas may be large and pedunculated and lobular. They are frequently familial and inherited as an autosomal dominant. Note the Brooke Spiegler syndrome.
There are two types, the lymphocutaneous and the fixed type. It is due to Sporothrix Schenkii. It starts as a papulopustular nodule that ulcerates and has an undermined edge and is usually painless. The very rare disseminated form occurs. The fixed form grows best at 33º centigrade and the lymphocutaneous at 37º centigrade, hence the pattern and location. The fixed form is usually acral. You can culture excised tissue. The differential diagnosis is atypical mycobacterial infection and rarely blastomycosis.
Angiomatous Tumours
Benign include multiple progressive haemangioma, Klippel-Trenauney syndrome, glomus tumour, Campbell de Morgan, pyogenic granuloma and angiokeratoma. The malignant angiomatous tumours include angiosarcoma, Kaposi’s sarcoma and lymphangiosarcoma.
Lymphangiomas are either lymphangioma circumscriptum or cystic hygromas. There is also the lymphangiosarcoma of Stewart and Treaves. It presents generally like a little bruise.
