Soft Tissue and Bone

Soft Tissue Lesions

SPINDLE CELL, PLEOMORPHIC AND CONNECTIVE TISSUE TUMORS 1. Fibrohistiocytic Spindle Cell Tumors 2. Schwannian/Neural Spindle Cell Tumors 3. Spindle Cell Tumors of Muscle 4. Melanocytic Spindle Cell Tumors 5. Tumors and Proliferations of Angiogenic Cells 6. Tumors of Adipose Tissue 7. Tumors of Cartilaginous Tissue 8. Tumors of Osseous Tissue

MCQ 1 An 85 year old man undergoes a skin and soft tissue excision biopsy for an ill-defined nodule on the posterior neck measuring 4cm in diameter: Histologically the epidermis is atrophic but otherwise normal. The sundamaged dermis shows a pleomorphic epithelioid cells with many mitotic figures which extends into the subcutaneous tissue. Focal vascoformative pattern is seen.

Immunohistochemically, the tumour cells are positive for CD31, CD34 and focally for MNF116. It is negative for S100, HHV8, smooth muscle actin and desmin.

The most likely diagnosis is: a. Spindle cell carcinoma b. Kaposi’s sarcoma c. Atypical fibroxanthoma d. Malignant melanoma e. Angiosarcoma

Answer

E Angiosarcoma

Differential diagnosis & Immuno’ panel • • • • •

AFX (atypical fibroxanthoma) - SMA Spindle cell SCC – CK + Melanoma – HMB 45, S100 Leiomyosarcoma – SMA, DESMIN, CK +/MPNST (peripheral nerve sheath tumour) – S100 +/-, CD34 +/• DFSP (dermatofibrosarcoma protuberans) CD 34 + • Kaposi Sarcoma – CD34 +, HHSV8 +, CD31• Angiosarcoma - CD31+, CD31 +, CK +/-

Fibrohistiocytic Spindle Cell Tumors • • • • • • • • • • • • • •

Hypertrophic Scar Keloid Dermatofibroma (cellular) Dermatofibrosarcoma Protuberans Atypical Fibroxanthoma Malignant Fibrous Histiocytoma Fibrous Papule (Angiofibroma) Recurrent Infantile Digital Fibromatosis Acquired Digital Fibrokeratoma Giant Cell Tumor of Tendon Sheath Nodular Fasciitis Mucocele Digital Mucous Cyst Cutaneous Myxoma

Benign Fibrous Histiocytoma • Also called dermatofibroma, sclerosing haemangioma, histiocytoma cutis • Common (3% population) • Predilection of extremities • Middle aged females • Significant association with previous trauma • Eruptive lesions in the context of immunosuppression, HIV infection and HAART

Salient Features • • • • • • •

? Reactive or neoplastic Hyperplastic Epidermis Ill defined dermal lesion extending into superficial subcutis Interlacing fascicles of spindles cells Fibroblast-like cells and histiocytes Secondary elements (histiocytes, giant cells, haemosiderin Hyalinised collagen bundles surrounded by tumour cells in the periphery • No atypia

Immunohistochemistry F13a expression

CD34 expression

Discussion- DF variants • Numerous variants including: Cellular; Atypical; Aneurysmal; Clear Cell; Halo; Granular; Muxoid; Keloidal; ‘Monster cell’; Lipidised; Angiomatous • Uncertain significance • Nosological relationship to classical BFH remains unclear

Cellular variant Calonje E, Mentzel T, Fletcher CD. Am J Surg Pathol. 1994 Jul;18(7):668-76.

• • • • • • • •

74 cases Young or middle-aged adults Wide anatomic distribution 26% recurred locally Commonly fascicular growth pattern Moderate mitotic rate Extension into subcutis (33%) Foci of central necrosis (12%)

Atypical 'pseudosarcomatous' variant Kaddu S, McMenamin ME, Fletcher CD Am J Surg Pathol. 2002 Jan;26(1):35-46

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59 cases Mainly extremities, age range 5-79 years Proliferation of pleomorphic, plump, spindle cells Background classic DF Mitotic figures 1 -15 / 10 hpf Atypical mitoses (n=20) Geographic necrosis (n=7) Local recurrences (n=3) Distant metastases (n=2)

MCQ 2 A 40 year old man with a plaque like lesion on the chest.

Histology shows a dermal cellular spindle cell lesion with a storiform pattern and stains positively for CD34 and negative for CD31, EMA, SMA, Desmin and S100. No epidermal attachment is seen.

The most likely diagnosis is: a. Spindle cell carcinoma b. Kaposi’s sarcoma c. Dermatofibrosarcoma Protuberans d. Malignant melanoma e. Angiosarcoma

DFSP (Dermatofibrosarcoma Protuberans)

• Slow growing locally aggressive tumour • 3rd and 4th decade • Trunk and proximal extremities • Multinodular cutaneous mass several cm in diameter • Local recurrence 20 – 50 % • Metastasis exceedingly rare – less than 0.3%

Salient Features • Dermal and subcutaneous spindle cell tumour • Monomorphic cells • Storiform growth pattern infiltrating subcutis in a lace-like pattern • Minimal mitotic activity (5/ 10 hpf) • No secondary elements • Ring Chromosome (17:22) • Related to Giant cell fibroblastoma

CD34

DFSP • Variants: • Bednar tumour - pigmented; • Fibrosarcomatous – recurrence 70%; metastasis 20%, loss of CD34; • Myoid; Myxoid; Granular Cell; Atrophic; Sclerosing; Palisaded; GCF;

Differential Diagnoses • • • • • • •

Cellular dermatofibroma Neurofibroma Fibrosarcoma Perineurioma Spindle cell AFX Sarcomatoid Carcinoma Melanoma

Differential diagnosis & Immuno’ panel • • • • •

AFX (atypical fibroxanthoma) - SMA Spindle cell SCC – CK + Melanoma – HMB 45, S100 Leiomyosarcoma – SMA, DESMIN, CK +/MPNST (peripheral nerve sheath tumour) – S100 +/-, CD34 +/• DFSP (dermatofibrosarcoma protuberans) CD 34 + • Kaposi Sarcoma – CD34 +, HHSV8 +, CD31• Angiosarcoma - CD31+, CD31 +, CK +/-

AFX • Coined by Helwig for a cutaneous tumour with marked cellular pleomorphism, yet with a course that is benign.

• View modified in view of rare reports of metastases • Solitary, head and neck of elderly

Immunohistochemistry Negative ? CD10 not specific

Fibrohistiocytic Spindle Cell Tumors • • • • • • • • • • • • • •

Atypical Fibroxanthoma Malignant Fibrous Histiocytoma Fibrous Papule (Angiofibroma) Recurrent Infantile Digital Fibromatosis Acquired Digital Fibrokeratoma Giant Cell Tumor of Tendon Sheath Nodular Fasciitis Mucocele Digital Mucous Cyst Cutaneous Myxoma Giant cell tumour of tendon sheath Synovial Sarcoma Fibrosarcoma MFH

MCQ 3 23 year old man presents with a rapidly growing soft tissue mass on the arm. Histology shows a cellular lesion with plump fibroblast and myofibroblast-like cells with oedema and red cell extravasation. Mitoses are seen but no atypical forms or nuclear pleomorphism. What is the most likely diagnosis?

A. DFSP B. MPNST C. Sarcomatoid carcinoma D. Nodular fasciitis E. Angiosarcoma

D. Nodular fasciitis

Nodular fasciitis • Reactive myofibroblastic proliferative process • Solitary painless, rapidly growing nodule over several weeks duration • Self-limiting, proper diagnosis is essential to avoid unnecessary aggressive treatment • Extremities and trunk • 10 – 20% of cases arise in the head and neck region • Circumscribed nodule of spindled cells dispersed in a myxoid matrix with a feathery appearance • Variable numbers of lymphocytes and hemorrhage • Variable collagenization, older lesions sometimes showing keloidal change • SMA positive, CD34 negative

Fibroma of tendon sheath • • • • • •

Reactive or neoplastic unclear 20-50 years, Males > Females, Slow growing Attached to tendon, Usually painless Hands and feet Well circumscribed, Encapsulated, Lobulated Dense hyalinized collagenous stroma; myxoid change sometimes present • Slit-like vascular channels, Fibroblast like cells • No cytological atypia or mitotic activity • Occasionally foamy histiocytes and osteoclast-like giant cells may be seen

Giant cell tumor of tendon sheath • • • • • • • • •

Female predominance 30-50 years Hand most commonly affected Feet, ankles and knees less often involved Sharply circumscribed with mature collagenous pseudocapsule Dense fibrous stroma generally present Polygonal cells with eosinophilic cytoplasm and vesicular nuclei Multinucleate giant cells Hemosiderin-laden histiocytes, xanthoma cells and inflammatory cells • Mitotic figures sometimes conspicuous • Foci of hemorrhage commonly seen

Giant cell tumor of tendon sheath • • • • • • • • •

Female predominance 30-50 years Hand most commonly affected Feet, ankles and knees less often involved Sharply circumscribed with mature collagenous pseudocapsule Dense fibrous stroma generally present Polygonal cells with eosinophilic cytoplasm and vesicular nuclei Multinucleate giant cells Haemosiderin-laden histiocytes, xanthoma cells and inflammatory cells • Mitotic figures sometimes conspicuous • Foci of hemorrhage commonly seen

EMQ A Questions 1-5 • Answers will show during these slides • Chance to recap each answer after the 5 questions

A. B. C. D. E. F. G. H. I. J. K. L. M. N.

EMQ 4 1.

Pyogenic granuloma Synovial sarcoma Epithelioid sarcoma Ewing’s Sarcoma Giant cell tumour of tendon sheath Xanthoma Epithelioid haemangioma Schwannoma Neurofibroma Angiolipoma Spindle cell lipoma Elastofibroma Solitary fibrous tumour Nodular fasciitis

H. Schwannoma A 35 year old man with nodule on the arm. Dermal lesion which is encapsulated and has S100 spindle cells in loose myxoid stroma and more hypercellular areas.

Palisading of nuclei is seen.

A. B. C. D. E. F. G. H. I. J. K. L. M. N.

Pyogenic granuloma Synovial sarcoma Epithelioid sarcoma Ewing’s Sarcoma Giant cell tumour of tendon sheath Xanthoma Epithelioid haemangioma Schwannoma Neurofibroma Angiolipoma Spindle cell lipoma Elastofibroma Solitary fibrous tumour Nodular fasciitis

EMQ 4 2.

K. Spindle cell lipoma

A 44 year old builder with a nodule on the back of the neck. The nodule has spindle cell areas, ropey collagen and fat. There is no atypia and the tumour is CD34 positive.

A. B. C. D. E. F. G. H. I. J. K. L. M. N.

EMQ 4 3.

Pyogenic granuloma Synovial sarcoma Epithelioid sarcoma Ewing’s Sarcoma Giant cell tumour of tendon sheath Xanthoma Epithelioid haemangioma Schwannoma Neurofibroma Angiolipoma Spindle cell lipoma Elastofibroma Solitary fibrous tumour Nodular fasciitis

C. Epithelioid sarcoma

A 27 year old man presents with a nodule on the foot. The tumour is epithelioid, malignant with central areas of necrosis and is EMA +, CD34 + and AE1/AE3. S100 negative.

A. B. C. D. E. F. G. H. I. J. K. L. M. N.

EMQ 4 4.

Pyogenic granuloma Synovial sarcoma Epithelioid sarcoma Ewing’s Sarcoma Giant cell tumour of tendon sheath Xanthoma Epithelioid haemangioma Schwannoma Neurofibroma Angiolipoma Spindle cell lipoma Elastofibroma Solitary fibrous tumour Nodular fasciitis

L. Elastofibroma

32 year old female with papules around the eye.

Histology shows bland foamy cells in the dermis.

A. B. C. D. E. F. G. H. I. J. K. L. M. N.

EMQ 4 5.

Pyogenic granuloma Synovial sarcoma Epithelioid sarcoma Ewing’s Sarcoma Giant cell tumour of tendon sheath Xanthoma Epithelioid haemangioma Schwannoma Neurofibroma Angiolipoma Spindle cell lipoma Elastofibroma Solitary fibrous tumour Nodular fasciitis

B. Synovial sarcoma 31 year old male with a mass around the knee.

Histology shows a biphasic tumour with spindle cells and epithelioid cells. Cytogenetics shows t(x:18) translocation and radiology confirms pulmonary deposits

Recap Answers • • • • •

1-H. Shwannoma 2-K. Spindle cell lipoma 3-C. Epithelioid Sarcoma 4-L .Xanthoma 5-B. Synovial sarcoma

Monophasic synovial sarcoma • Adults in the 3rd to 5th decades • Monomorphic population of spindle cells with high nuclear cytoplasmic ratio & relatively little intervening stroma • Tapering nuclei & scant cytoplasm • Herringbone growth pattern sometimes evident • Mitotic activity often high • More than 90% of patients have a t(X;18) translocation mutation • Not related to synovium • At least focal pankeratin and/or EMA positive

Fibrosarcoma • True/ pure adult fibrosarcomas exceptionally rare outside the setting of transformed dermatofibrosarcoma protuberans • Classic herringbone pattern - parallel sheets of cells arranged in intertwining whorls • Well-differentiated forms have multiple plump fibroblasts with deeply staining nuclei in a rich collagen background • High-grade lesions- very cellular, with marked cellular atypia & mitotic activity.

• Sparse matrix • S100 protein negative

Malignant fibrous histiocytoma (MFH) • • • • •

• • • •

Controversy exists over the term MFH Best regarded as an undifferentiated pleomorphic sarcoma Affects elderly Malignant pleomorphic cells obscured by an intense inflammatory infiltrate Designation appropriate for lesions were a clear line of differentiation is not apparent Tumors to exclude include sarcomas, lymphoid, epithelial and melanocytic tumors Broad spectrum immunohistochemistry panel is often necessary This case preceded the immunohistochemistry era.

Anaplastic T-cell lymphoma should be particularly considered in the differential diagnosis

Schwannian/Neural Spindle Cell Tumors • • • • • • •

Traumatic neuroma Neurofibromas Neurofibromatosis Schwannoma (Neurilemmoma) Palisaded Encapsulated Neuroma Accessory Digit MPNST

Traumatic Neuroma • Peripheral hyperplastic response to peripheral nerve injury • Any age, any site • Histopathology: • Variably defined but unencapsulated mass of axons and Schwann cells embedded in scar tissue

Neurofibromatosis • • • • •

Neurocutaneous syndromes NF1 NF2 Tuberous sclerosis Von Hippel Lindau Syndrome

Neurofibroma • • • • • • • • • • •

Commonest tumour of nerve sheath origin Majority are solitary Younger age group than schwannoma If widespread consider NF Histology Well defined but unencapsulated dermal or subcutaneous nodule Loosely arranged spindle cells with wavy nuclei. Mast cells are seen.

Often extensive fat infiltration Delicate fascicles Minimal nuclear pleomorphism Immuno’ – S100 protein, CD34, NF

Plexiform

Schwannoma (Neurilemmoma) Neurilemmoma: this tumor consists of plump spindle cells showing a marked tendency to palisade.

Palisaded Encapsulated Neuroma

Malignant Peripheral Nerve Sheath Tumor (MPNST) • Rare tumor; often occur in patients with neurofibromatosis 1 • A sarcoma is defined as a MPNST when at least one of the following criteria is met: • Lesion arises from a peripheral nerve • Lesion arises from a preexisting benign nerve sheath tumor (usually neurofibroma, rarely schwannoma) • It demonstrates Schwann cell differentiation on histologic examination

• Most often in adults

Malignant Peripheral Nerve Sheath Tumor (MPNST) • Anatomical distribution wide • Dense cellular fascicles alternate with myxoid regions; herringbone pattern • Marbleized pattern describes the swirling arrangement of intermixed dense & myxoid areas • Spindled-cells with very irregular contours to rounded or fusiform cells • Nuclear palisading seen in less than 10% of cases & even then, only focally • Features suggestive of malignancy include invasion of surrounding tissues, invasion of vascular structures, nuclear pleomorphism, necrosis, & mitotic activity.

• Characteristic perivascular condensation of tumor cells is a useful diagnostic feature (Fig.2) • 80-85% of MPNSTs are spindle cell tumors with a fascicular growth pattern similar to a fibrosarcoma

Grading Sarcomas • French Trojani grading system widely used; based on 3 parameters - tumor differentiation, mitotic index, & tumor necrosis.

• The National Cancer Institute system is based on tumor histologic type and subtype, location, and the amount of tumor necrosis, but cellularity, nuclear pleomorphism, and mitotic index are also considered for some tumor types.

Spindle Cell Tumors of Muscle • • • •

Leiomyoma Angioleiomyoma Smooth Muscle Hamartoma Leiomyosarcoma

Pilar Leiomyoma • • • • • • • • •

Young adults, Limbs and trunk Lesions are multiple, painful or tender Association with HIV, CLL, and erythrocytosis Small proportion of cases FH and AD inheritance (Rudner et al) Ill defined intradermal lesion which merges imperceptibly with the surrounding connective tissue Unaffected epidermis Uniform interlacing bundles of cells with elongated cells with brightly eosinophilic cytoplasm and blunt ended nuclei.

Immuno’ – SMA, Desmin, h-caldesmon Genital leiomyoma

Angioleiomyoma • • • • • • • •

Common, deep dermal or subcutaneous tumours Adults 30 – 60 years Predilection for legs Females 2: Males 1 Consistent loss of Chromosome 22 Histology Rounded encapsulated lesions Interlacing bundles of uniform smooth muscle cells distributed around numerous small vessels of variable wall thickness • May contain adipose tissue

Leiomyosarcoma • 2 types: • Cutaneous – include nipple • Subcutaneous – vulval and scrotal

Leiomyosarcoma Cutaneous • Derived from arrector pili • Often young adults esp. Males • Local recurrence common • Mets very rare • Histology • Ill-defined diffuse lesion • Variable pleomorphism and increased mitotic activity

Leiomyosarcoma Sub-cutaneous • Closely related to deeper SM tumours • 5th – 7th Decade on the Limbs • Local recurrence common • 50% metastasise, mortality 30–50% • > 5cm poor prognosis • Histology: nodular lesion; marked pleomorphism, mitotic activity, necrosis and haemorrhage

Melanocytic Spindle Cell Tumors Desmoplastic and neurotropic variant of spindle cell Melanoma Desmoplastic MM – high degree of fibroblastic and myofibroblastic metaplasia accompanied by abundant collagen synthesis.

Neurotropic MM – metaplasia directed towards Schwann cell differentiation

Spindle cell melanoma • Arise in elderly (61 years mean) • Mainly head and neck • Leg in females • Desmoplastic MM described in oral cavity • Recurrence 22-77%; mets 11-56% • Prognosis similar to classical MM

S100

Other Tumour Groups Tumors and Proliferations of Angiogenic Cells • • •

• • • • • • • • • • • •

Pyogenic Granuloma (Lobular Capillary Hemangioma) Intravascular Papillary Endothelial Hyperplasia (Masson's HemangioEndotheliome Vegetant Intravasculaire) Stasis Dermatitis with Vascular Proliferation (Acroangiodermatitis, PseudoKaposi's Sarcoma) Kaposi's Sarcoma Cutaneous Angiosarcoma Angiokeratoma Arteriovenous Hemangioma Cavernous Hemangioma Cherry Hemangioma Microvenular Hemangioma Cutaneous Lymphangioma Venous Lake Epithelioid Hemangioendothelioma Glomangioma Subungual Glomus Tumor

Vascular tumours - KS Four epidemiological varieties described: Classic KS: • Indolent disease; Affects elderly men • Mediterranean region, or of Eastern European descent, Jews Endemic KS • Middle-aged males, mainly from sub-Saharan Africa; Generally indolent • Infiltrates the skin extensively, especially lower limbs; Visceral or nodal disease in children, aggressive behavior Transplant Related KS • Especially when associated with cyclosporine Epidemic KS • An aggressive disease in HIV/AIDS patients

Vascular tumours - KS • • • • • • • • • • • • • • •

3 Clinical stages: patch, plaque and nodular Vasoproliferative lesion Dermal but may extend into subcutis (usually plaque and nodular lesions) Proliferation of numerous irregular vascular spaces Vascular channels parallel to the epidermis May show ‘Promontory’ sign Mild to moderate endothelial cell atypia Intracytoplasmic eosinophilic, hyaline globules Extravasated red blood cells and hemosiderin Histiocytes, lymphocytes and plasma cells Patch stage: features may be subtle showing plasma cells associated with increase in slit-like vascular spaces in the upper dermis.

Plaque stage: eosinophilic spindle cells more prominent Nodular stage: multi-nodular; eosinophilic spindle cells in a fascicular pattern CD34 (diffuse) and CD31 (focal) positivity Human Herpes-virus 8 positive (99% cases)

Cutaneous angiosarcoma • Different clinical setting (head and neck of the elderly; post-irradiation, background of lymphoedema) • Cytologic atypia • Endothelial cell multi-layering • Mitoses • Dissection of collagen bundles • Can mimic KS and in difficult cases immunohistochemistry will help make the distinction (Angiosarcoma: CD31 diffuse staining, HHV8 negative)

Other Tumour Groups Tumors of Adipose Tissue • Naevus Lipomatosus Superficialis • Lipoma • Angiolipomas • Spindle Cell Lipoma • Pleomorphic Lipomas • Liposarcoma

Spindle cell lipoma • Mainly middle aged males (45 – 60 years old) • Subcutaneous tissue of the posterior neck, shoulder, back • Also can present in dermis • Mature fat cells, bland spindled cells set in a myxoid matrix • Characteristic thick bands of birefringent collagen.

• Spindle cells CD34 positive.

Liposarcoma • Atypical lipomatous tumour • Well-differentiated liposarcoma • Myxoid

• Differentiated

Well-differentiated liposarcoma • Typically occurs in the retro-peritoneum • Fatty tumour; stromal spindle cells • Scattered atypical, multi-nucleate cells

• Typical lipoblasts confirm the diagnosis

Small Blue Round Cell tumours • • • • • • • • •

Desmoplastic small round blue cell tumour Ewing's Sarcoma Leukaemia, Acute Mesothelioma, small cell Neuroblastoma (n-myc) Primitive neuroectodermal tumour (neural diff.)

Rhabdomyosarcoma Wilm's tumor Melanoma

Sarcomas

•Cytogenetics •Must learn them!

DISEASES OF BONES AND JOINTS

Diseases of bone Metabolic bone diseases Osteoporosis Osteomalacia Trauma Fracture Infection Osteomyelitis Tumours Metastases Haematological Primary

Osteoporosis

Osteomalacia

Vitamin D deficiency Kidney failure Liver failure Skin = Vit D precursors Active Vit D = Liver

Kidney

absorption of Ca2+ from bowel

Fracture healing Rapid repair; Starts immediately; Complete healing

Haemorrhage New lamellar Bone

Fibroblast ingrowth (wound healing) Endochondral ossification

Cartilage

De novo woven bone

Osteomyelitis

Bone tumours Most common Metastasis Breast Kidney Bronchus Next most common Haematological Myeloma Leukaemia Rare Primary bone tumours Named after type of matrix e.g. Osteoblastoma Malignant ones metastasise to lungs

Other Tumour Groups Tumors of Cartilaginous Tissue

Tumors of Osseous Tissue • Albright's Hereditary Osteodystrophy and Osteoma Cutis • Conditions to Consider in the Differential Diagnosis

EMQ B Questions 1-5 • Answers will show during these slides • Chance to recap each answer after the 5 questions

Options a. Telangiectatic osteosarcoma b. Osteoblastoma c. Giant cell tumour M. Mesenchymal chondrosarcoma d. Chondrosarcoma e. Osteochondroma A 19-year-old male f. Periosteal osteosarcoma presents with a jaw g. Adamantinoma of the bone h. Aneurismal cyst tumour, the microscopy of i. Simple cyst which, shows j. Fibrous dysplasia differentiated cartilage and k. Parosteal osteosarcoma a distinctive small cell l. Conventional osteosarcoma component. In areas, the m. Mesenchymal chondrosarcoma tumour is reminiscent of n. Ewing’s sarcoma haemangiopericytoma o. Chordoma p. Osteoid osteoma

EMQ B Question 1

Options a. Telangiectatic osteosarcoma b. Osteoblastoma c. Giant cell tumour d. Chondrosarcoma e. Osteochondroma f. Periosteal osteosarcoma g. Adamantinoma of the bone h. Aneurismal cyst i. Simple cyst j. Fibrous dysplasia k. Parosteal osteosarcoma l. Conventional osteosarcoma m. Mesenchymal chondrosarcoma n. Ewing’s sarcoma o. Chordoma p. Osteoid osteoma

EMQ B Question 2 O. Chordoma A child presents with cranial nerve deficits and a lobulated soft tumour is excised from the cervical vertebrae. The tumour is S100 and EMA positive.

Options a. Telangiectatic osteosarcoma b. Osteoblastoma c. Giant cell tumour d. Chondrosarcoma e. Osteochondroma f. Periosteal osteosarcoma g. Adamantinoma of the bone h. Aneurismal cyst i. Simple cyst j. Fibrous dysplasia k. Parosteal osteosarcoma l. Conventional osteosarcoma m. Mesenchymal chondrosarcoma n. Ewing’s sarcoma o. Chordoma p. Osteoid osteoma

EMQ B Question 3 K. Parosteal osteosarcoma A 19- year-old female shows a superficial diaphyseal tumour with sunburst mineral arrays and it does not involve the medulla. In microscopy malignant chondroid matrix mixes with osteoid.

Options a. Telangiectatic osteosarcoma b. Osteoblastoma c. Giant cell tumour d. Chondrosarcoma e. Osteochondroma f. Periosteal osteosarcoma g. Adamantinoma of the bone h. Aneurismal cyst i. Simple cyst j. Fibrous dysplasia k. Parosteal osteosarcoma l. Conventional osteosarcoma m. Mesenchymal chondrosarcoma n. Ewing’s sarcoma o. Chordoma p. Osteoid osteoma

EMQ B Question 4 F. Periosteal osteosarcoma A 35-year-old female presents with inability to flex the knee. A metaphyseal tumour is seen on the posterior aspect of distal femur, which encircles the bone.

Options A. Telangiectatic osteosarcoma B. Osteoblastoma C. Giant cell tumour D. Chondrosarcoma E. Osteochondroma F. Periosteal osteosarcoma G. Adamantinoma of the bone H. Aneurismal cyst I. Simple cyst J. Fibrous dysplasia K. Parosteal osteosarcoma L. Conventional osteosarcoma M. Mesenchymal chondrosarcoma N. Ewing’s sarcoma O. Chordoma P. Osteoid osteoma

EMQ B Question 5 C. Giant Cell Tumour A lytic cystic red brown epiphyseal tumour is excised from the distal femur of a 25year-old woman. You are told that in order to differentiate this tumour from the mimics, you have to check the calcium levels on this patient.

Recap the Answers 1-

M. This affects the young adults

2-

O.Physaliferous cells is a hallmark

3K.Affects women, 10 years older than those conventional 4-

F.This tumour also is called juxtacortical

5C.Calcium for hyperparathyroidism and brown tumour

Diseases of Synovial Joints

Trauma Haemarthrosis Inflammatory Infection Crystal induced Primary inflammatory Rheumatoid disease Non-inflammatory Osteoarthritis NO TUMOURS

MCQ 6 A 44 year old man complains of swollen, tender and warm, knee joint. A biopsy of synovium shows villous hypertrophy, chronically inflamed tissue with lymphoid follicles and plasma cells.

He most likely diagnosis is: a. b. c. d. e.

Septic arthritis Osteoarthritis Rheumatoid arthritis Psoriatic arthritis None of the above

Rheumatoid disease

Inflamed synovium (pannus) grows over and destroys articular cartilage

Villous synovium

Subluxation

Autoimmune inflammation

Osteoarthritis Focal

Cartilage loss Osteophyte Subarticular bone sclerosis

Cyst formation

Starts at surface

Process extends to deep layers By cleft formation

Eburnation

Septic arthritis

Crystal arthritis

Gout

Pseudogout

Any Questions?