Johnstone 2024 Soft Tissue Masses I & II.pdf

SOFT TISSUE MASSES I & II Mathew Johnstone DPM, FACFAS D.ABPM Assistant Professor College of Podiatric Medicine and Surgery Des Moines University COPYRIGHT NOTICE This presentation may contain copyrighted material used for educational purposes under the guidelines of Fair Use and the TEACH Act. It i...

SOFT TISSUE MASSES I & II Mathew Johnstone DPM, FACFAS D.ABPM Assistant Professor College of Podiatric Medicine and Surgery Des Moines University COPYRIGHT NOTICE This presentation may contain copyrighted material used for educational purposes under the guidelines of Fair Use and the TEACH Act. It is intended only for use by students enrolled in this course. Reproduction or distribution is prohibited. Unauthorized use is a violation of the DMU Integrity Code and may also violate federal copyright protection laws. LECTURE OBJECTIVES Demonstrate knowledge of common soft tissue masses affecting the lower extremity. Demonstrate knowledge of the imaging characteristics of common soft tissue masses affecting the lower extremity. Demonstrate knowledge of the rationale and techniques for biopsy. Demonstrate knowledge of the general approach to soft tissue mass excision, including incision, preservation of local anatomy and closure. GETTING STARTED Often the site of the tumor will be immediately obvious, or this will be the presenting complaint ­ ­ ­ ­ Can arise from previous trauma/infections Composed of any soft-tissue cell type Many different types: both benign and malignant Treatment varies based on type (diagnosis must be first prior to treatment) The key to successful management of any tumor is a proper diagnosis HISTORY Important questions to ask of the patient at first presentation ­ Age of the lesion? ­ Growth of the lesion? ­ Recent uptick in growth? ­ Some STM may shrink with time as well. ­ Any previous trauma? ­ Infections ­ Burns ­ Chronic wounds ­ Painful? ­ Most are painless initially. Do not neglect to ask past medical history and family history HISTORY Does patient or family members have a history of cancers? Patients with a previous history of malignancy are at risk for metastases to the foot and ankle. ROS Patients may not correlate seemingly unrelated symptoms with tumor presentation Be sure to double check: ­ ­ ­ ­ ­ ­ ­ ­ New pains Weight loss Weight gain Malaise N/V Headaches Tingling or numbness Muscle weakness PHYSICAL EXAMINATION: MEASUREMENT Measure dimensions on the skin surface using a metric ruler Lesions under 3cm are more often benign Lesions over 5cm have a higher chance of being malignant Where exactly is the lesion in relationship to the underlying anatomy? (near joints? / Tendons?) Remember that malignancy is RARE PHYSICAL EXAMINATION: PALPATION Feel the mass with your fingers, describe what you are feeling using medical terminology ­ Flaccid (soft) ­ Firm (hard) ­ Nodular/ well defined (one solitary lesion) ­ Diffuse (hard to tell where one stops, and another begins) ­ Lobulated: many lumps coalesced together ­ Tender/Nontender PHYSICAL EXAM: MOBILIZE Try to move the lesion, and the skin above it ­ ­ ­ ­ Does it move freely? Is it bound to the skin? Is it bound or attached to the bone? Does it move when you mobilize the adjacent tendons? ­ Try to appreciate the depth of the lesion ­ Subcutaneous? ­ Deep? PHYSICAL EXAM: TRANSILLUMINATION Finally, a good use for that Pen-Light Place a light source adjacent to the mass Turn off the lights in the room and turn on the pen light Does the mass illuminate throughout the area of the lesion? ­ Fluid (or air) filled lesions will illuminate Benign lesions Malignant lesions Less than 3cm diameter Greater than 5cm diameter Near the Joint line Away from joint line +/- Pain Can be painless Superficial Deep Fleshy/soft Firm Mobile Fixed Transillumination No transillumination (solid) Well-defined mass Defined mass CLINICAL FEATURES REVIEW : BENIGN VS MALIGNANT LESIONS DIAGNOSTIC IMAGING OVERVIEW Plain film radiography Computed Tomography Magnetic Resonance Imaging Ultrasonography Positron Emission Tomography Nuclear Medicine Identify any calcific or radio-opaque densities within the mass Establish any connections with bones and joints ­ Bone tumors will be its own lecture Abdominal and Chest tumors are often detected using plain film which are also used for monitoring RADIOGRAPHS ­ In addition to special contraststudies for visceral organs. COMPUTED TOMOGRAPHY Traditional CT scans do not provide as much soft tissue contrast as MRI, there is still a place for this modality Can be used to help differentiate some tumors from infections ­ Top image: intra-osseous gas from an infection which was originally thought to be a bone tumor on MRI. Can be used to note the pattern of mineralization in soft tissue masses ­ Bottom image: peripheral mineralization pattern of myositis ossificans DUAL ENERGY CT A relatively new technology (2006) utilizing CT scans taken at 80 kVp and then again at 140 kVp Particularly useful in distinguishing gouty tophi from other soft tissue masses Color coded images and 3-d reconstruction were used to distinguish this gouty tophus from the bone of the tibia as monosodium urate and bone have different radiographic uptakes MAGNETIC RESONANCE IMAGING Excellent soft tissue contrast (especially with injectable contrast media) T1 phase of the MRI generally provides better detail Knowledge of the exact location of the mass from pre-mri exams can allow for use of a smaller field of view, making a more detailed image. ­ Top: standard Field of view MRI for hip ­ Bottom: Detailed smaller Field of view of the same lesion showing much more detail. MRI/CT IMAGING PLANES MRI and CT utilize image “slices” of the anatomy taken in the cardinal planes Note that in some, anatomical landmarks may not be evident Shown: Ledderhose disease (palmar fibromatosis) which is nearly identical to plantar fibromatosis, the tumor (*) is easily seen and the palmar aponeurosis (in our case plantar fascia) is marked with an arrow. ­ On the transverse plane view, this relationship is nearly impossible to see. DIAGNOSTIC ULTRASOUND Useful for lesions superficial to the deep fascial layer Can help distinguish edema from localized mass Can show if the lesion is fluid-filled (cystic) or solid ­ Can also show fluid around a tendon vs a mass Echogenicity aides in diagnosis ­ Top: fluid filled ganglion cyst (homogenous well-defined hypoor anechoic) ­ Bottom: Lipoma (homogenous, well defined hyper/isoechoic) POSITRON EMISSION TOMOGRAPHY Similar to Nuclear medicine scans in that a radionucleotide is injected and the imaging is used to detect the radiation given off by the substance. PET detects the metabolism of different organs by attaching the radioactive substance to a naturallyutilized chemical (like glucose for brain PET) Used to locate both metastases and primary tumors, and track response to therapy. NUCLEAR MEDICINE Does not show detailed information about tumor Used to localize and detect metastatic tumors Can be used to gauge response to treatment. LABORATORY WORKUP There is no specific bloodwork for any soft tissue tumor Adjunct testing can help to rule out other similar conditions ­ ESR ­ CRP ­ CBC ­ Uric Acid ­ Rheumatoid factor ­ Lactate dehydrogenase (sometimes use to track and stage tumors, this and other chemicals like PSA (prostate stimulating antigen) are often produced by healthy tissues as well and are nonspecific for tumors. BIOPSY Provides tissue for histopathological analysis Several samples often required to confirm diagnosis. Several types ­ ­ ­ ­ ­ Excisional Incisional Open biopsy Fine Needle Core Needle WHEN TO BIOPSY Presumed benign lesion with symptoms All presumed malignant lesions Patients with concerning history or exam findings. NOTES ON BIOPSIES Lesions that are suspected to be malignant should be biopsied at the planned treatment center This expedites care Biopsies performed off-site are more likely to lead to misdiagnoses, delays and poor outcomes. Assume that the biopsy tract is going to become contaminated with tumor cells Biopsy site must be in-line with surgical incision so that tract can also be removed Biopsy site must not violate more than one anatomical compartment, avoid n/v bundles. EXCISIONAL BIOPSY Lesion is removed entirely and sent for pathological identification Recommended for lesions which are symptomatic and presumed to be benign (well encapsulated, small) Examples include lipoma, ganglion cysts NOT recommended for suspected malignancy INCISIONAL BIOPSY The “gold standard” for diagnosis of soft tissue tumors High diagnostic accuracy (94-100%) Cn be used for large lesions, or indeterminate diagnoses Complications include ­ Hematoma ­ Spread of tumor ­ Wound-healing issues OPEN BIOPSY TYPES Rules for both excisional and incisional biopsies ­ Longitudinal incision ­ Incision parallel to the long axis of the limb ­ Shortest route to lesion ­ Keep it to one anatomical compartment ­ Avoid the neurovascular anatomy ­ Maintain hemostasis ­ Bleeding may carry tumor cells to other parts of the body ­ NO exsanguination ­ Use intra-operative frozen section ­ Biopsy should be carried out at definitivetreating facility FROZEN SECTION At large treatment centers, specialist pathology experts can diagnose tumors and distinguish benign from malignant features in minutes A cryostat machine (pictured top left) is used to freeze the sample A microtome is then used to “slice” the sample for immediate stain and analysis Frozen sections are more difficult to read than traditional paraffin fixed samples ­ Advantage: can give intra-operative results and margins NEEDLE BIOPSIES: FINE NEEDLE A fine-needle biopsy involves aspiration of fluid contents of a cystic lesion, or injection of saline and reaspiration which may include some tumor cells Can be guided by Ultrasound Less accurate compared to other methods ­ Up to ¼ of patients diagnosed with this method require a second biopsy ­ More useful for fluid filled lesions NEEDLE BIOPSIES: CORE NEEDLE Modification of the fine needle Lower contamination risk compared to incisional ­ Multiple samples often needed Improved accuracy by removing a “core” of tissue ­ Sensitivity of 81%-100% ­ Specificity of 91%-100% Large hospitals and cancer treatment facilities commonly sit a regular panel of experts from multiple specialties who review cases This can add a level of expert review and teamcoordination for a challenging diagnosis TUMOR BOARD Physicians are invited to send tumor-cases to the board for review prior to surgical treatment. COMMON BENIGN MASSES OF THE FOOT AND ANKLE Cysts Giant cell tumor (of tendon sheath) Lipoma Fibroma Fibromatosis Pigmented Villonodular Synovitis Neurilemmoma (Schwannoma) Hemangioma and Glomus tumor Most common soft tissue tumor in the foot and ankle ­ 1/3 benign lesions ­ Synovial cysts and ganglion cysts are often indistinguishable Origin likely traumatic Diagnosis is largely clinical ­ Supported by diagnostic radiology and aspirate GANGLION CYST GANGLION CLINICAL PRESENTATION Small Solitary Mobile Transilluminates readily Becomes taught with tendon or joint contraction Changes in size GANGLION ULTRASOUND FEATURES Ultrasound is often the most useful diagnostic tool for in-office identification Can be used to distinguish cyst (fluid filled) from non-cystic tumors Ganglion are: ­ ­ ­ ­ Hypoechoic or anechoic Smooth Well defined Can show septation GANGLION MRI Smooth Synovial cysts located at joint line ­ May show a “stalk” Well circumscribed Fluid filled Homogenous signal intensity ­ Hypointense on T1 weighted MRI ­ Hyperintense on T2 weighted MRI TREATMENT Observation ­ Asymptomatic lesion Aspirate contents ­ High recurrence rate ­ Lower rate with injection of steroid after aspiration ­ Requires positive diagnosis (send first aspiration to path) Excision ­ Recurrence rate of about 10% MUCOID CYST Common toe cyst Arising from synovial lining ­ Most commonly DIPJ More common on fingers More typical in adults 50-70 MUCOID CYST CLINICAL FEATURES Distal digit Translucent to flesh-colored May involve the nail bed ­ Causes grooving or split nail Usually, painless May be associated with mallet-toe May be solitary or multinodular Transilluminates MUCOID CYST ULTRASOUND AND MRI Ultrasound ­ ­ ­ ­ ­ Hypo or anechoic Smooth Well defined Homogenous May be several others nearby MRI ­ T2 weighted images show high signal intensity ­ Sharp borders ­ Useful for distinguishing nail-bed cyst from other nail bed tumors TREATMENT Observation Expression ­ For ruptured cysts Aspiration Excision ­ Semi-elliptical incision DIPJ arthrodesis ­ For recurrences LIPOMA More common between 40-60 years of age Begin slow-growing mass Comprised of fatty cells Can occur anywhere in the body where fat cells are present LIPOMA CLINICAL FEATURES Slow growth Usually, painless ­ Large lipomas can compress nerves Subcutaneous in most ­ Deep are more painful Flesh colored Equally transilluminates with skin More common on the back, neck, shoulder, abdomen, and proximal extremity LIPOMA MRI Will appear equal to other areas of anatomic fat T1 hyperintense, T2 intermediate signal T2 with fat-suppression shows low signal Minimal enhancement with contrast LIPOMA TREATMENT Observation Marginal excision ­ Remove tumor and some surrounding healthy tissue ­ Recurrence depends on size and location ­ Subcutaneous tumor is less likely to recur than intramuscular FIBROMA Also known as Ledderhose’s Disease for describer Dr Georg Ledderhose (1894) Comprised of Spindle cells, and collagen fibrils (fibrous tumor) Associated with the plantar (or palmar) fascia 2 subtypes ­ Deep (desmoid fibromatosis) ­ Superficial CLINICAL FEATURES Firm, lobulated, does not transilluminate, +/- pain, more prominent with dorsiflexion of great toe (Hubscher) Deep Fibromatosis ­ Locally aggressive, although benign ­ Can involve tendon sheath and tissues deep to the plantar fascia ­ Spreads along fascia, nerve or tendon sheath ­ 75% recurrence after excision Superficial ­ More common ­ Limited to the plantar fascia ­ Both may present in unison with ­ Frozen shoulder ­ Diabetes ­ Dupuytren’s contracture/palmar fibromatosis PLANTAR FIBROMATOSIS ULTRASOUND Single (rarely multiple) Well demarcated Iso-echoic with plantar fascia (hypoechoic) “Thickening” of plantar fascia No calcifications or fluid PLANTAR FIBROMA MRI Fusiform thickening of the plantar fascia Typically, low signal intensity on T1 and T2 ­ Fibrous tissue tumor ­ Some inflamed lesions can appear high signal on fluidsensitive imaging. FIBROMA TREATMENT Observation Orthotics ­ “plantar fascial groove” Intra lesional steroid injection ­ Painful initial injection ­ Softens and atrophies lesion Surgical excision Topical therapy with verapamil ESWT Radiation therapy The land of dubious evidence SURGICAL RESECTION OF PLANTAR FIBROMATOSIS Use relaxed long incision Consider placement in relation to tension lines, anatomy ­ Medial plantar artery and nerve Wide excision of mass needed ­ Min. 2cm ­ High recurrence (up to 80%) SURGICAL RESECTION (COMPLICATIONS) Local resection: high recurrence rate (57100%) Injury to medial plantar artery or nerve. Scarring, nerve entrapment Hypertrophic plantar scar Wound dehiscence Loss of plantar arch PVNS A benign of the synovium (thin lining of joints) causing it to thicken and overgrow Most often in young adults 20-50 years of age Mono-articular Can be local or diffuse Longstanding lesions can locally erode bone/joints (this is not a metastatic invasion) Characterized by villous, nodular or both types of proliferations of the synovium stained with hemosiderin Often diagnosed by aspiration (bloody) PVNS CLINICAL FEATURES Located at joints ~1 per 100,000-person incidence Often nebulous onset Joint pain and swelling “Catching”, “Locking”, stiffness, or instability Gradual onset Symptoms may “come and go” PVNS IMAGING Plain film ­ Radiographs normal in most (70% plus) ­ Some show erosions and sclerosis of bone ­ Older lesions MRI ­ Periarticular, or synovial mass ­ May show varied bone erosion ­ Low signal on all sequences (due to hemosiderin deposition and hemorrhage) PVNS TREATMENT Observation Diffuse PVNS ­ ­ ­ ­ Open synovectomy High recurrence rate Radiation adjunct treatment Rarely requires amputation Localized PVNS ­ Solitary nodules may be removed arthroscopically GIANT CELL TUMOR OF THE TENDON SHEATH Similar in appearance/histology and etiology to PVNS Arises from synovium of tendon sheath, not joint Appears in 3rd-5th decade Slightly more common in female patients More common in hand and wrist ­ Most common soft tissue tumor of the hand GCTTS CLINICAL FEATURES Slow growing Often painless soft tissue growth Located along tendon-course Older lesions may erode and destroy bone and cartilage GCTTS IMAGING Plain film ­ Rarely invade bone and mimic intra-osseous lesions ­ Pressure-erosions seen in up to 15% MRI ­ Method of choice for imaging of GCTTS ­ Low T1 and T2 signal intensity ­ Moderate enhancement with contrast (top) TREATMENT OF GCTTS Complete surgical excision of tumor Recurrences can be re-excised NEURILEMMOMA (SCHWANNOMA) Arises from the perineurium (peripheral nerve sheath) Peak incidence 50-60 y/o Derived from Schwann Cells (responsible for producing myelin) Nerve is displaced by the tumor eccentrically One of the two most common nerve sheath tumors ­ Neurofibroma is the other SCHWANNOMA CLINICAL FEATURES More common on flexor surface Soft, often painless tumor Follows course of peripheral nerve Can be mobilized orthogonal (perpendicular) to nerve course NOT longitudinally along nerve course May present with paresthesia and numbness May exhibit positive Valleix sign SCHWANNOMA IMAGING MRI ­ Scan of choice for diagnosis ­ T1 iso-intensity ­ T1 with contrast: intense enhancement ­ T2 heterogenous hyperintensity ­ “Split fat sign” ­ Thin rim of peripheral fat ­ “Target sign” ­ Usually on intracranial schwannoma ­ Peripherally high T2 signal SCHWANNOMA TREATMENT Observation Surgical excision ­ Marginal excision (resection through the pseudo-capsule or reactive-tissue envelope of tumor) ­ Spare nerve from excision ­ Epineurium is opened carefully opposite the nerve fascicles and mass is gently separated from epineurium and nerve fascicles ­ Excision sometimes causes nerve damage or compromises affected nerve ­ which type of CRPS would this cause? HEMANGIOMA Benign growth derived from blood vessels Formed when small vessels multiply at abnormal rate Most common pediatric soft tissue tumor HEMANGIOMA CLINICAL FEATURES Appear during the first week or so of life Blue or pink macular lesion visible on skin “Rubbery” texture “Red birthmark” May elevate from skin , however, Most begin involution/shrinking with completion by 4 year of age Complete resolution is possible The word hemangioma is sometimes mis-applied to acquired tumors of adulthood such as cherry hemangioma HEMANGIOMA SUBTYPES Capillary hemangioma Most common type Small capillaries that are normal in size and diameter, but high in number tightly packed Cavernous hemangioma Made up of larger blood vessels that are dilated Blood vessels are not as closely packed the spaces (or "caverns") between them are filled with blood Bluish swelling underneath the skin Compound hemangioma Mix of the capillary and cavernous types Lobular capillary hemangioma Pyogenic granuloma HEMANGIOMA IMAGING Ultrasound ­ Echogenic, well-defined mass which exhibits vascular flow on color doppler U/s MRI ­ T1 intermediate, T2 hyperintense ­ Characteristic “bag of worms” appearance Observation For infantile hemangioma: beta blocker medication Anti-inflammatory medication Compression Embolization: destruction of feeding vessels HEMANGIOMA TREATMENT ­ Often employed prior to resection for cavernous type to reduce intraoperative blood loss HEMANGIOMA EXCISION Surgical excision usually reserved for cavernous or destructive lesion Once removed use compression Provide specific instructions as to activity restrictions to guide recovery Note high recurrence rate Observe for hemorrhage GLOMUS TUMOR A tumor arising from the glomus body: a feature of the dermis which is comprised of an arteriovenous shunt surrounded by connective tissue. ­ The role of this organ is to shunt blood away form the skin when it is exposed to cold temperatures, and more blood to the skin when it is warm. The tumor often appears during the 2nd-4th decade of life Blue-red blanchable papules Most common in the deep subcutaneous fat of fingers and toes or under the nail bed GLOMUS TUMOR CLINICAL EXAMINATIONS Loves test ­ Using a pin or pencil, apply pressure to specific parts of the nail plate, intense pain will be elicited when the pressure is localized directly over the suspected mass Hildreth’s sign ­ Apply a tourniquet to the toe, pain and tenderness should transiently disappear, then reappear (often worse than before) once tourniquet is released. Cold sensitivity ­ Patient may self-report pain intensifies when digit is exposed to cold ­ Can also apply an ice-cube in clinic GLOMUS TUMOR: IMAGING Plain film: nondiagnostic for the lesion itself, can be useful to rule out other pathologies of the nail bed such as exostosis of the distal phalanx. Ultrasound: color-doppler U/s will reveal intra-tumor vasculature MRI: ­ T1: well defined, hypointense ­ T2: well defined, hyperintense, with contrast enhancement GLOMUS TUMOR TREATMENT Glomus tumors are benign ­ Asymptomatic lesions should be observed For symptomatic lesions: ­ Complete surgical excision of the nail unit (include matrix if this is involved) ­ Recurrence rate is elevated for skin-colored glomus tumors or those with nail matrix involvement. ­ Final images are at postop 6 weeks and 1-year final followup ­ Inform patients that nail deformities are expected following resection. MALIGNANT SOFT TISSUE MASSES What makes a mass malignant? Malignare’- Late Latin “Contriving maliciously” or “evil” In the medial sense ­ Cells which invade other tissue: Malignant ­ Cells which do not infiltrate or Invade other tissue: Benign. ­ Benign tumors CAN ­ Impinge on nerves/other structures causing pain ­ Cause pressure-erosions in bone Sarcoma: (Greek sárkōma, meaning “fleshy growth,” ) Derived from connective tissue that supports and connects body structures (fat, muscles, nerves, tendons, joints, blood vessels, lymph vessels, cartilage, or bone) Carcinoma: (Greek, karkínōma, “sore, ulcer, cancer.”) Derived from Skin or tissue covering the surface of organs and glands TUMOR NOMENCLATURE Lymphoma: (Latin lympha ("water") and from Greek -oma ("morbid growth, tumor").Derived from lymphatic or body’s immune system Leukemia: (Greek words leukos, "white," and haima, "blood.“) Derived from blood COMMON (NON SKIN) SOFT TISSUE MALIGNANCIES OF THE LOWER EXTREMITY Synovial Sarcoma Clear cell Sarcoma Fibrosarcoma Epithelioid Sarcoma SOFT TISSUE SARCOMAS Rare: 1.4 per 100,000 ­ Over age 80: rises to 8 per 100,000 Prognostic factors ­ Tumor size ­ >5cm = Worse prognosis ­ Tumor Depth ­ Deep = worse prognosis ­ Grade ­ Higher grades denote a worse prognosis ­ Metastases ­ Mets present = Worse prognosis ENNEKING/TGNM STAGING OF SOFT TISSUE SARCOMA 80 SYNOVIAL SARCOMA 5-10% of soft tissue sarcoma ­ Most common foot and ankle Softtissue sarcoma Peak incidence between 15 and 35 years of age Origin thought to be undifferentiated mesenchymal cells May metastasize to regional lymph notes SYNOVIAL SARCOMA: CLINICAL FEATURES Slow growing Often painful mass Located on extremities in 80% of cases Pari-articular regions ­ Tendon sheaths, bursae, joint capsules SYNOVIAL SARCOMA IMAGING Plain film Nonspecific findings of diffuse STM around joints Calcifications which may be eccentric or peripheral Involvement of underlying bone not uncommon CT Heterogeneous deep-seated soft-tissue mass with attenuation similar to or slightly lower than that of muscle Intense enhancement with contrast helps to distinguish this from cystic lesion MRI Imaging of choice T1: “heterogeneous multilobulated soft-tissue mass with signal intensity similar to or slightly higher than that of muscle” T2: “Triple signal sign”: areas of Hypointensity, Isointensity and Hyperintensity vs. fat With contrast displays heterogenous enhancement TREATMENT: SYNOVIAL SARCOMA Wide surgical excision ­ Unless this is your sub-specialty, do not attempt Proximal Amputation ­ High grade tumors with unresectable margins SYNOVIAL SARCOMA PROGNOSIS 5 year survival rates vary significantly, ranging from 36 to 76% Large tumor size (> 5 cms), presence of bone or neurovascular invasion were found to be associated with the development of distant metastasis and decreased disease specific survival Patients with tumors that present with more than 20% of poorly differentiated patterns have the worse prognosis 50% of the patients with Synovial Sarcoma develop metastases Other prognostic factors have been correlated with an increase in the local recurrence rate including; proximal location of the tumor or positive margin after resection 85 1% of all soft tissue sarcomas Aggressive, melanocytic sarcoma Typically, high grade “Melanoma of the soft parts” CLEAR CELL SARCOMA CLEAR CELL SARCOMA: CLINICAL FEATURES Unknown etiology Women slightly more than men in 3rd and 4th decades of life. Palpable mass of varied duration (months to years) Painful in less than 50% of cases (1/3 to 1/2 exhibit pain) Most common in deep seated regions of the extremity (aponeuroses, tendons) CLEAR CELL SARCOMA IMAGING Xrays ­ Soft Tissue swelling MRI ­ May appear benign ­ T1: Homogenous Slight Hyperintensity or isointense vs. muscle ­ T2: heterogenous, variable signal intensity CLEAR CELL SARCOMA TREATMENT Radiation and chemotherapy have not been shown to be effective primary treatment modalities Surgical removal is the mainstay of treatment Wide local excision, aggressive resection, or amputation often with adjuvant radiotherapy are the current standards of care Clear cell sarcomas have high rates of local recurrence, distant metastases and lymph node metastases (12-43%). The overall survival rate for 5 years is 60%. FIBROSARCOMA Rare adult neoplasm of fibroblasts More common in 3rd through 8th decades More common in trunk and upper extremity FIBROSARCOMA CLINICAL FEATURES Occurs in deep soft tissues May also appear as primary bone tumor “Round-ish” lesion Diffuse swelling Difficulty moving the limb Pathology: “Herringbone pattern” ­ Interlacing sheets of spindle-like fibroblasts FIBROSARCOMA IMAGING CT ­ Nonspecific area of iso-attenuated soft tissue mass MRI ­ T1: hypointense ­ T2: hyperintense ­ Enhances with contrast FIBROSARCOMA TREATMENT Infantile form (