6Myxoid Liposarcoma Myxoid and round cell same category Adults; deep-seated in extremities (thigh)Histology:multinodular with increased cellularity at periphery of nodulesmyxoid matrix, occ. with mucin poolstypical delicate branching vesselsbland round to oval mesenchymal cells and univacuolated lipoblastsprogression to round cell LPS histological continuumGenetics: t(12;16)(q13;p11), t(12;22)(q13;q12)
733y old male patient, 4cm deep soft tissue tumour right forearm. Case 18319/05:33y old male patient, 4cm deep soft tissue tumour right forearm.
16Intramuscular Myxoma Important DD for myxoid soft tissue tumours Middle-aged to older adults; large muscles of limb girdlesHistology:macro circumscribed, but micro infiltrativeextensive myxoid matrix, hypocellularbland stellate- and spindle-shaped cellsNO mitoses, pleomorphism, necrosis
1777y old male patient, 4cm superficial mass right upper arm. Case 34761/09:77y old male patient, 4cm superficial mass right upper arm.
26Extraskeletal Myxoid Chondrosarcoma Rare soft tissue sarcomaMiddle-aged to older adults; extremities, limb girdles and other sites; often haemorrhagicHistology:multinodularchondromyxoid matrixcords and networks of cellseosinophilic cytoplasm, uniform nuclei, few mitosesfocal S100, occ. cytokeratin and EMAGenetics: t(9;22(q22;12), t(9;17)(q22;q11), t(9;15)(q22;q21)
27Case 30750/03:15y old male patient, large pelvic mass and lymphadenopathy as well as mediastinal and lung lesions on CT. Groin node biopsied.
39Desmoplastic Small Round Cell Tumour Small round blue cell tumour showing divergent differentiationChildren and adolescents, esp. male; abdominal cavity, retroperitoneum, pelvisHistology:nests of variable size surrounded by desmoplastic stromasmall uniform cells with round nuclei,occ. rhabdoid inclusionsepithelial, smooth muscle and neural markers positive, esp. CK, EMA and desmin (dot-like), WT1Genetics: t(11;22)(p13;q12)
40Case 24640/04:42y old male patient, small nodule in the subcutis of the right buttock.
49Proliferative Fasciitis A small fibroblastic proliferation similar to nodular fasciitis, but with large ganglion-like cellsMiddle-aged and older adults; subcutis, esp. extremities; rapid growthHistology:ill-definedtissue-culture fibroblastsmyxoid/collagenous stromalarge, ganglion-like cells with prominent nucleoli
50Case 3821/03:18y old female patient, calcified soft tissue mass right thigh, recent increase in size, vague history of trauma.
54Myositis Ossificans Localized, reparative lesion Any age, mostly young adults; anywhere; history of trauma; rapid growthHistology:zonation!centre resembling nodular fasciitisthen immature unmineralized boneperiphery mature bone
5561y old female patient, 4cm tumour in gastric fundus. Case 17062/04:61y old female patient, 4cm tumour in gastric fundus.
59GIST KIT-positive mesenchymal tumours primarily of the GI-tract Middle-aged and older adults; stomach, small bowel, rectum & colon in that order (rare oesophagus and elsewhere)Histology:fascicular architecturespindle cells or epithelioid cells, rarely pleomorphicCD117 (c-kit), DOG1, CD34, occ. SMA, desmin, S100behaviour depending on site, max. diameter, mitoses
6060y old male patient, 10cm tumour around left common iliac vessels. Case 5365/04:60y old male patient, 10cm tumour around left common iliac vessels.
64Leiomyosarcoma Soft tissue type Middle-aged and older adults; retroperitoneum, large vessels and other soft tissue sitesHistology:typical fascicular patterneosinophilic cytoplasm and blunt-ended nucleihyalinization, myxoid changeSMA, desmin and caldesmonocc. poorly differentiated, pleomorphic areas (“dedifferentiated”)
6533y old female patient, soft tissue tumour abdominal wall. Case 14986/04:33y old female patient, soft tissue tumour abdominal wall.
75Inflammatory Myofibroblastic Tumour Heterogenous group of tumours; primarily, a visceral and soft tissue tumour in children and adolescents often with ALK gene rearrangementLung, abdomen, bladder most common sitesHistology:myofibroblasts in fascicular or storiform patternmatrix myxoid to collagenizedinflam. infiltrate of lymphocytes, plasma cells, eosinophilsSMA, occ. desmin and CK, ALK in 50%
7645y old female patient, 5cm soft tissue tumour left calf. Case 3356/04:45y old female patient, 5cm soft tissue tumour left calf.
80Schwannoma Benign nerve sheath tumour All ages; almost any nerve Histology:capsule!thick-walled, hyalinized vessels!Antoni A and B areas, Verocay bodiescystic degeneration, hyalinization, nuclear atypia, calcification, foam cells, haemorrhagecellular, ancient and plexiform variants
8163y old female patient, 17.5cm mass left upper quadrant of abdomen. Case 7859/04:63y old female patient, 17.5cm mass left upper quadrant of abdomen.
86Solitary Fibrous Tumour Cellular SFT syn. to haemangiopericytomaMiddle-aged adults; extrapleural variant at any siteHistology:circumscribed, patternlessalternating hypo- and hypercellular areashyalinized collagenhaemangiopericytomatous vascular patternsmall bland cells, few mitosesCD34 90%, CD99 70%, BCL2 30%, occ. EMA & SMA
8769y old male patient, deep soft tissue mass left thigh. Case 14005/03:69y old male patient, deep soft tissue mass left thigh.
92Dedifferentiated Liposarcoma In up to 10% of well-diff. liposarcomasAdults; retroperitoneum, spermatic cord and other sitesHistology:often abrupt transitionwell-differentiated componentdedifferentiated component, low or high grademostly “MFH”-type, but also heterologous differentiationIHC: CDK4, MDM2
9359y old female patient, 3.3kg / 26cm tumour retroperitoneum. Case /07:59y old female patient, 3.3kg / 26cm tumour retroperitoneum.
118Angiomatoid Fibrous Histiocytoma Peculiar small tumour in skin or subcutisChildren and young adults; extremities, trunk, head & neck, often at sites of normal LNHistology:3 componentscapsule with lymphoplasmacytic infiltrateblood-filled cystic spacesproliferation of fibrohistiocytic or myofibroblastic cellsdesmin, EMA, CD68, CD99 in half of casesGenetics: t(12;22)(q13;q12), t(12;16)(q13;p11), t(1;22)(q33;q12)
11965y old male patient, recurrent deep soft tissue tumour left thigh. Case 34141/04:65y old male patient, recurrent deep soft tissue tumour left thigh.
130Alveolar Soft Part Sarcoma Rare soft tissue sarcomaAdolescents and young adults; extremities (adults) and head and neck (children); slow growthHistology:distinct nested pattern, central discohesionround uniform nuclei, granular cytoplasmvascular invasion!DPAS-positive crystalsTFE3, occ. muscle markersGenetics: t(X;17)(p11;q25)
131Cases 17157/02 & 37608/03:17157/02: 61y old female patient, rapidly growing recurrent soft tissue tumour left foot.37608/03: 32y old male patient, growing painful soft tissue mass right thigh.
139Synovial Sarcoma Relatively frequent soft tissue sarcoma Young adults; deep-seated in extremities, but any site possibleHistology:cellular!biphasic, monophasicepithelial element in solid nests, glandsspindle cells in vague fascicleshyalinisation, calcification, ossificationEMA, cytokeratin (7 & 19), BCL2, CD99, S100Genetics: t(X;18)(p11;q11), t(X;20)(p11;q13)
14068y old female patient, recurrent tumour scalp. Case 8960/04:68y old female patient, recurrent tumour scalp.