Concise Soft Tissue Tumours

Question 1

Spinal Muscular Atrophy

Answer 1

autosomal recessive, defect in SMN1 gene. Atrophy of cell leads to denervation

Question 2

Muscular Dystrophy

Answer 2

Duchenne MD = No Dystrophin, 2/3 of cases are familial, symptoms by age 5, duck-like Gait
Hands on knees to stand. Pseudohypertrophy of calves. Wheel chair by age 10. Survive
Until 35.
Becker MD = Abnormal Dystrophin. Later onset with mild sympotms. Muscle necrosis, then replaced by fat.
Female carriers have risk of higher creatine kinase. Survive past 40.

Question 3

Myotonic Dystrophy

Answer 3

Autosomal Dominant, tri-nucleotide repeat. Most common adult MD. Sustained involuntary contraction of muscles, with sagging face.

Question 4

Malignant Hyperpyrexia

Answer 4

muscle spasms, tachycardia, tachypnea, due to anesthetic inhalation and cytosolic
Ca control mutation.

Question 5

Dermatomyositis

Answer 5

Skin and Muscle inflammation. Classic upper eyelid violaceous discoloration and edema.
Proximal muscles affected symmetrically. 25% of patients have malignancy. Perifascicular myocyte atrophy = myocytes dying around blood vessel

Question 6

Polymyositis

Answer 6

Only Muscle effected, mainly in adults. T-Cell mediated injury necrotic tissue throughout
fascicle.

Question 7

Inclusion Body Myositis

Answer 7

Asymmetric, starts distally. Vacuoles in biopsy.

Question 8

Myasthenia Gravis

Answer 8

Autoimmune attack of ACh nicotinic receptor. Associated with Thymic hyperplasia or
thymoma. Treat with anti-cholinesterase.

Question 9

Lambert-Eaton Myasthenia Syndrome

Answer 9

Autoimmune attack of Ca channels. Paraneoplastic syndrome

(probably have cancer).

Question 10

Causes of elevated creatine kinase.

Answer 10

Creatine Kinase = signal for muscle damage
Acute Myocardial Infarct = Check for CK-MB and Troponin I
Skeletal Muscle Dystrophies = Check for total CK
Cerebrovascular accidents

Question 11

Describe in one or two sentences the classification scheme for mesenchymal/soft tissue tumors.

Answer 11

Mesenchymal Proliferation of extra skeletal, non-epithelial tissue.
Classified as what they differentiate into.
Classified as Benign and Malignant (sarcoma). Benign outnumber Malignant 100:1.
Can occur anywhere.
Some Chromosomal abnormalities can be used as markers

Question 12

State the most common type of genetic abnormality in soft tissue tumors.

Answer 12

Neurofibromatosis Type 1
Gardner Syndrome
Osler-Weber-Rendu Syndrome

Question 13

Factors of prognostic importance for soft tissue tumors

Answer 13

Histological Classification = Look at cells and pattern of cells using immune stain
Histological Grade = scored based on differentiation, mitotic count, necrosis, histological grade
Staging of Tumor = TNM scale (Tumor, lymph Node, Metastasis)
Superficial vs. Deep Seated tumor = better prognosis for superficial
Size = Smaller better

Question 14

State which imaging modality is most helpful in the assessment of soft tissue tumors of the extremities.

Answer 14

MRI and Biopsy

Question 15

Lipoma

Answer 15

Most Common soft tissue tumor, Benign

Question 16

Conventional Lipoma

Answer 16

Mature Fat, superficial

Question 17

Angiolipoma

Answer 17

Fat + Blood Vessel, superficial

Question 18

Spindle-Cell Lipoma

Answer 18

Spindle Cells + Fat, superficial

Question 19

Intermuscular Lipoma

Answer 19

Overgrowth of fat in muscles

Question 20

Lipoblastoma

Answer 20

Overgrowth of Fat in infants, due to steroids

Question 21

Liposarcoma

Answer 21

Usually in deep soft tissue or retroperitoneum, Metastatic
Well-Differentiated = rarely metastasize, but likely to recur.
Myxoid/Round Cell = Intermediate Malignancy
Pleomorphic = Aggressive metastatic

Question 22

Reactive Pseudosarcomatous Proliferations

Answer 22

Look like sarcomas, no sharp border, grows quickly

Question 23

Nodular Fasciitis

Answer 23

Painful mass on upper extremeties of young adults after trauma. Has only been
present for a few weeks. Rarely recurs.

Question 24

Myositis Ossificans

Answer 24

Deep lesion of proximal extremities following trauma. Outer margin develops
osteoblasts.

Question 25

Superficial Fibromatosis

Answer 25

Benign, include fascia or aponeurosis.

Palmar Fibromatosis = Duptuytren’s Contracture
Plantar Fibromatosis = on foot
Penile Fibromatosis = on penis

Question 26

Deep-Seated Fibromatosis

Answer 26

Benign, often recur. Usually in teens → 30 yr olds. Often mutated APC gene
Abdominal = Often during/after pregnancy
Extra-Abdominal = Chest, back, thigh
Intra-Abdominal = Pelvic side walls, associated with Familial Adenomatosis Polyposis

Question 27

Fibrosarcoma

Answer 27

Malignant, common in deep soft tissue of extremities.

Fibromatosis Colli = Scar reaction of Sternocleidomastoid in newborns

Question 28

Fibrohistiocytic Tumor

Answer 28

Fibroblast + Tissue Macrophage

Question 29

Dermatofibroma

Answer 29

skin, benign

Question 30

Dermatofibrosarcoma Protuberans

Answer 30

intermediate malignancy, can be confused for dermatofibroma

Question 31

Malignant Fibrous Histiocytoma

Answer 31

High malignancy, high recurrence. Bizarre multinucleated cells.
Has been reclassified

Question 32

Rhabdomyoma

Answer 32

Benign muscle (cardac or skeletal)

Question 33

Rhabdomyosarcoma

Answer 33

Muscle, very aggressive, most common childhood sarcoma
Embryonal = In head or neck of younger than 10 yr old
Alveolar = Middle Adolescence
Pleomorphic = rarest, in deep soft tissue of adults

Question 34

Leiomyoma

Answer 34

Most common in uterus, well circumscribed

smooth muscle

Question 35

Leiomyosarcoma

Answer 35

Common in uterus or GI, can be anywhere smooth muscle.

Question 36

Hemangioma

Answer 36

Benign, commonly in skin, can be anywhere

blood vessels and lymph

Question 37

Pyogenic Granuloma

Answer 37

Benign, in skin

blood vessels and lymph

Question 38

Lymphangioma

Answer 38

Benign, containing lymph, can be associated with Turner’s Syndrome
Glomus Tumor = Painful, arteriovenous structures in distal digits
Vascular Ectasias = Inflammation of preexisting vessels
Nevus Flammeus = Birth Mark
Spider Angiomas = Autosomal Dominant disease
Hereditary Hemorrahagic Telangiectasia = Autosomal Dominant
Bacillary Angiomatosis = Caused by infection from Bartonella bacteria

Angiosarcoma = Malignant, aggressive, often in skin. Can be secondary to radiation therapy.
Hemangioendotheliomas = Very Rare Malignant Vascular tumors.
Kaposi’s Sarcoma = Human Herpes Virus Type 8, purple patches on skin
Chronic
Lymphadenopathic = African Children
Transplant-Associated
HIV-Associated

blood vessels and lymph

Question 39

Norton Neuroma

Answer 39

repeated minor trauma

peripheral nerve

Question 40

Traumatic Neuroma

Answer 40

crushed nerve leading to tangled nerve fibers

peripheral nerve

Question 41

Schwannoma

Answer 41

Benign, Associated with NF2

peripheral nerve sheath tumor

Question 42

Neurofibroma

Answer 42

Benign, Associated with NF1
Cutaneous = solitary in peripheral nerve
Plexiform = Infiltrating peripheral nerve, causes significant deficit
peripheral nerve sheath tumor

Question 43

Malignant Peripheral Nerve Sheath Tumor

Answer 43

Malignant, associated with NF1

peripheral nerve sheath tumor

Question 44

Giant Cell Tumor or Tendon Sheath

Answer 44

Generally fingers and wrist
Diffuse form = Knee, ankle, and foot
synovial lesion

Question 45

Synoval Sarcoma

Answer 45

Malignant, NOT synovial differentiation, occurs around joints, often calcifications present

Question 46

Ganglion Cyst

Answer 46

MYXOMATOUS LESIONS

located in joints (wrist), feels like bubble, not neoplasm

Question 47

Describe, in no more than a few sentences, the key differences between NF1 and NF2.

Answer 47

Neurofibromatosis = Dominant disease

Type 1 = More common, Café au lait spots, Plexiform neurofibromas, neurodevelopmental problems
Type 2 = Bilateral acoustic schwannomas in CN VIII