1. Soft Tissue Pathology The Sort of Thing You Get in Exams!
Dr. Petra Dildey
Royal Victoria Infirmary Newcastle upon Tyne

2. 50y old male patient, soft tissue mass left popliteal fossa.
Case 38551/03:
50y old male patient, soft tissue mass left popliteal fossa.

3. Case 38551/03

4. Case 38551/03

5. Case 38551/03

6. Myxoid Liposarcoma Myxoid and round cell same category
Adults; deep-seated in extremities (thigh)
Histology:
multinodular with increased cellularity at periphery of nodules
myxoid matrix, occ. with mucin pools
typical delicate branching vessels
bland round to oval mesenchymal cells and univacuolated lipoblasts
progression to round cell LPS histological continuum
Genetics: t(12;16)(q13;p11), t(12;22)(q13;q12)

7. 33y old male patient, 4cm deep soft tissue tumour right forearm.
Case 18319/05:
33y old male patient, 4cm deep soft tissue tumour right forearm.

8. Case 18319/05

9. Case 18319/05

10. Case 18319/05

11. Case 18319/05

12. Low Grade Fibromyxoid Sarcoma
Rare soft tissue sarcoma
Young to middle-aged adults; extremities and trunk; deep
Histology:
circumscribed, low to moderate cellularity
alternating fibrous and myxoid stroma
bland spindle cells, whorled pattern
arcades of blood vessels
occ. giant collagen rosettes
Genetics: t(7;16)(q33;p11)

13. 48y old female patient, 6.5cm intramuscular tumour left buttock.
Case 35841/03:
48y old female patient, 6.5cm intramuscular tumour left buttock.

14. Case 35841/03

15. Case 35841/03

16. Intramuscular Myxoma Important DD for myxoid soft tissue tumours
Middle-aged to older adults; large muscles of limb girdles
Histology:
macro circumscribed, but micro infiltrative
extensive myxoid matrix, hypocellular
bland stellate- and spindle-shaped cells
NO mitoses, pleomorphism, necrosis

17. 77y old male patient, 4cm superficial mass right upper arm.
Case 34761/09:
77y old male patient, 4cm superficial mass right upper arm.

18. Case 34761/09

19. Case 34761/09

20. Case 34761/09

21. Myxofibrosarcoma Rel. common fibroblastic sarcoma; myxoid MFH
Elderly patients; limbs and limb girdles; subcutaneous and deep
Histology:
multinodular with fibrous septa
myxoid stroma
atypical spindle-/stellate-shaped cells, occ. pseudolipoblasts
curvilinear vessels

22. 66y old male patient, haemorrhagic soft tissue tumour right calf.
Case 19222/04:
66y old male patient, haemorrhagic soft tissue tumour right calf.

23. Case 19222/04

24. Case 19222/04

25. Case 19222/04

26. Extraskeletal Myxoid Chondrosarcoma
Rare soft tissue sarcoma
Middle-aged to older adults; extremities, limb girdles and other sites; often haemorrhagic
Histology:
multinodular
chondromyxoid matrix
cords and networks of cells
eosinophilic cytoplasm, uniform nuclei, few mitoses
focal S100, occ. cytokeratin and EMA
Genetics: t(9;22(q22;12), t(9;17)(q22;q11), t(9;15)(q22;q21)

27. Case 30750/03:
15y old male patient, large pelvic mass and lymphadenopathy as well as mediastinal and lung lesions on CT. Groin node biopsied.

28. Case 30750/03

29. Case 30750/03

30. Case 30750/03 MyoD1

31. Alveolar Rhabdomyosarcoma
Small round blue cell tumour
10-25 years; often extremities, all other sites possible
Histology:
3 subtypes: typical, solid, mixed
nests separated by fibrovascular septa
small round nuclei, scant cytoplasm
horse-shoe giant cells common
Myogenin, MyoD1, desmin positive
Genetics: t(1;13)(p36;q14), t(2;13)(q35;q14)

32. Case 7739/06:
36y old female patient, large tumour tail of pancreas with liver metastases.

33. Case 7739/06

34. Case 7739/06

35. Case 7739/06

36. Case 7739/06

37. Case 7739/06 CK

38. Case 7739/06 Desmin

39. Desmoplastic Small Round Cell Tumour
Small round blue cell tumour showing divergent differentiation
Children and adolescents, esp. male; abdominal cavity, retroperitoneum, pelvis
Histology:
nests of variable size surrounded by desmoplastic stroma
small uniform cells with round nuclei,
occ. rhabdoid inclusions
epithelial, smooth muscle and neural markers positive, esp. CK, EMA and desmin (dot-like), WT1
Genetics: t(11;22)(p13;q12)

40. Case 24640/04:
42y old male patient, small nodule in the subcutis of the right buttock.

41. Case 24640/04

42. Case 24640/04

43. Case 24640/04

44. Nodular Fasciitis Small fibroblastic proliferation
All age groups, mostly young adults; subcutis!, anywhere in body; rapid growth
Histology:
partly loose/feathery, partly cellular
tissue-culture fibroblasts
mitotically active
collagen bundles, hyalinisation, giant cells
SMA positive, desmin negative

45. 50y old female patient, small subcutaneous tumour forearm.
NEQAS Case 261:
50y old female patient, small subcutaneous tumour forearm.

46. NEQAS Case 261

47. NEQAS Case 261

48. NEQAS Case 261

49. Proliferative Fasciitis
A small fibroblastic proliferation similar to nodular fasciitis, but with large ganglion-like cells
Middle-aged and older adults; subcutis, esp. extremities; rapid growth
Histology:
ill-defined
tissue-culture fibroblasts
myxoid/collagenous stroma
large, ganglion-like cells with prominent nucleoli

50. Case 3821/03:
18y old female patient, calcified soft tissue mass right thigh, recent increase in size, vague history of trauma.

51. Case 3821/03

52. Case 3821/03

53. Case 3821/03

54. Myositis Ossificans Localized, reparative lesion
Any age, mostly young adults; anywhere; history of trauma; rapid growth
Histology:
zonation!
centre resembling nodular fasciitis
then immature unmineralized bone
periphery mature bone

55. 61y old female patient, 4cm tumour in gastric fundus.
Case 17062/04:
61y old female patient, 4cm tumour in gastric fundus.

56. Case 17062/04

57. Case 17062/04

58. Case 17062/04 CD117 (c-kit)

59. GIST 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 architecture
spindle cells or epithelioid cells, rarely pleomorphic
CD117 (c-kit), DOG1, CD34, occ. SMA, desmin, S100
behaviour depending on site, max. diameter, mitoses

60. 60y old male patient, 10cm tumour around left common iliac vessels.
Case 5365/04:
60y old male patient, 10cm tumour around left common iliac vessels.

61. Case 5365/04

62. Case 5365/04

63. Case 5365/04
SMA
Desmin

64. Leiomyosarcoma Soft tissue type
Middle-aged and older adults; retroperitoneum, large vessels and other soft tissue sites
Histology:
typical fascicular pattern
eosinophilic cytoplasm and blunt-ended nuclei
hyalinization, myxoid change
SMA, desmin and caldesmon
occ. poorly differentiated, pleomorphic areas (“dedifferentiated”)

65. 33y old female patient, soft tissue tumour abdominal wall.
Case 14986/04:
33y old female patient, soft tissue tumour abdominal wall.

66. Case 14986/04

67. Case 14986/04

68. Case 14986/04

69. Fibromatosis Superficial and deep fibroblastic proliferations
Age depending on type; superficial: palmar, plantar etc., deep: extra-/intraabdominal
Histology:
think of it!
infiltrative margin
cellularity variable, fascicular architecture
bland spindle cells
collagen occ. hyalinized, prominent small arteries
SMA positive, desmin negative, beta-catenin

70. 9y old female patient, 13 cm tumour caecum.
Case 28715/05:
9y old female patient, 13 cm tumour caecum.

71. Case 28715/05

72. Case 28715/05

73. Case 28715/05

74. Case 28715/05 ALK

75. Inflammatory Myofibroblastic Tumour
Heterogenous group of tumours; primarily, a visceral and soft tissue tumour in children and adolescents often with ALK gene rearrangement
Lung, abdomen, bladder most common sites
Histology:
myofibroblasts in fascicular or storiform pattern
matrix myxoid to collagenized
inflam. infiltrate of lymphocytes, plasma cells, eosinophils
SMA, occ. desmin and CK, ALK in 50%

76. 45y old female patient, 5cm soft tissue tumour left calf.
Case 3356/04:
45y old female patient, 5cm soft tissue tumour left calf.

77. Case 3356/04

78. Case 3356/04

79. Case 3356/04

80. Schwannoma Benign nerve sheath tumour All ages; almost any nerve
Histology:
capsule!
thick-walled, hyalinized vessels!
Antoni A and B areas, Verocay bodies
cystic degeneration, hyalinization, nuclear atypia, calcification, foam cells, haemorrhage
cellular, ancient and plexiform variants

81. 63y 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.

82. Case 7859/04

83. Case 7859/04

84. Case 7859/04

85. Case 7859/04 CD34

86. Solitary Fibrous Tumour
Cellular SFT syn. to haemangiopericytoma
Middle-aged adults; extrapleural variant at any site
Histology:
circumscribed, patternless
alternating hypo- and hypercellular areas
hyalinized collagen
haemangiopericytomatous vascular pattern
small bland cells, few mitoses
CD34 90%, CD99 70%, BCL2 30%, occ. EMA & SMA

87. 69y old male patient, deep soft tissue mass left thigh.
Case 14005/03:
69y old male patient, deep soft tissue mass left thigh.

88. Case 14005/03

89. Case 14005/03

90. Case 14005/03

91. Case 14005/03

92. Dedifferentiated Liposarcoma
In up to 10% of well-diff. liposarcomas
Adults; retroperitoneum, spermatic cord and other sites
Histology:
often abrupt transition
well-differentiated component
dedifferentiated component, low or high grade
mostly “MFH”-type, but also heterologous differentiation
IHC: CDK4, MDM2

93. 59y old female patient, 3.3kg / 26cm tumour retroperitoneum.
Case /07:
59y old female patient, 3.3kg / 26cm tumour retroperitoneum.

94. Case /07

95. Case /07

96. Case /07

97. Case /07

98. Case /07 HMB SMA

99. Angiomyolipoma
Part of PEComas, can be associated with tuberous sclerosis
Adults, women>men; mostly kidneys
Histology:
mature fat / smooth muscle / thick-walled blood vessels
smooth muscle often focally epithelioid
IHC: HMB45, MelanA, SMA, occ. desmin
monotypic epithelioid variant!

100. 21y old female patient, 4cm mass in left tibialis anterior muscle.
Case 28802/10:
21y old female patient, 4cm mass in left tibialis anterior muscle.

101. Case 28802/10

102. Case 28802/10

103. Case 28802/10

104. Case 28802/10

105. Chondroid Lipoma A unique benign fatty tumour
Young adults, 80% women; prox. limbs & limb girdles; deep & subcutaneous
Histology:
lobulated, circumscribed, nests and cords of cells
epithelioid multivacuolated cells, cells with eosinophilic granular cytoplasm, mature adipocytes
myxoid and occ. hyaline matrix, vascular
Genetics: t(11;16)(q13;p12-13)

106. 14y old female patient, small soft tissue tumour left knee.
Case 158/07:
14y old female patient, small soft tissue tumour left knee.

107. Case 158/07

108. Case 158/07

109. Case 158/07

110. Case 158/07 SMA

111. Myofibroma Solitary or multicentric (myofibromatosis)
All ages, commonly in infants & children; solitary: skin, muscle, multiple: skin, viscera, muscle, bone
Histology:
apparently biphasic
plump myofibroblasts in whorls/bundles
primitive small round or short spindle cells
haemangiopericytomatos vascular pattern
hyalinization, calcification, necrosis, haemorrhage
SMA positive, desmin negative

112. 10y old boy, 2cm nodule right groin.
Case 4899/08:
10y old boy, 2cm nodule right groin.

113. Case 4899/08

114. Case 4899/08

115. Case 4899/08

116. Case 4899/08

117. Case 4899/08
EMA
Desmin

118. Angiomatoid Fibrous Histiocytoma
Peculiar small tumour in skin or subcutis
Children and young adults; extremities, trunk, head & neck, often at sites of normal LN
Histology:
3 components
capsule with lymphoplasmacytic infiltrate
blood-filled cystic spaces
proliferation of fibrohistiocytic or myofibroblastic cells
desmin, EMA, CD68, CD99 in half of cases
Genetics: t(12;22)(q13;q12), t(12;16)(q13;p11), t(1;22)(q33;q12)

119. 65y old male patient, recurrent deep soft tissue tumour left thigh.
Case 34141/04:
65y old male patient, recurrent deep soft tissue tumour left thigh.

120. Case 34141/04

121. Case 34141/04

122. Case 34141/04

123. Case 34141/04
Myogenin
MyoD1
Desmin

124. Pleomorphic Rhabdomyosarcoma
Rare RMS subtype in adults
Adults >45years; deep-seated in extremities most common
Histology:
haphazardly arranged bizarre cells with severely pleomorphic nuclei and deeply eosinophilic cytoplasm
tadpole and strap cells, occ. cross-striations
desmin, MyoD1, Myogenin

125. Case 33584/03:
35y old male patient, 12cm tumour in right iliac fossa adjacent to right psoas muscle, kidney and adrenal gland.

126. Case 33584/03

127. Case 33584/03

128. Case 33584/03

129. Case 33584/03 DPAS

130. Alveolar Soft Part Sarcoma
Rare soft tissue sarcoma
Adolescents and young adults; extremities (adults) and head and neck (children); slow growth
Histology:
distinct nested pattern, central discohesion
round uniform nuclei, granular cytoplasm
vascular invasion!
DPAS-positive crystals
TFE3, occ. muscle markers
Genetics: t(X;17)(p11;q25)

131. Cases 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.

132. Case 17157/02

133. Case 17157/02

134. Case 17157/02

135. Case 37608/03

136. Case 37608/03

137. Case 37608/03

138. Case 37608/03 EMA

139. Synovial Sarcoma Relatively frequent soft tissue sarcoma
Young adults; deep-seated in extremities, but any site possible
Histology:
cellular!
biphasic, monophasic
epithelial element in solid nests, glands
spindle cells in vague fascicles
hyalinisation, calcification, ossification
EMA, cytokeratin (7 & 19), BCL2, CD99, S100
Genetics: t(X;18)(p11;q11), t(X;20)(p11;q13)

140. 68y old female patient, recurrent tumour scalp.
Case 8960/04:
68y old female patient, recurrent tumour scalp.

141. Case 8960/04

142. Case 8960/04

143. Case 8960/04

144. Case 8960/04 CD31

145. Angiosarcoma Mostly cutaneous, rarely soft tissue
Skin: lymphoedema, post-irradiation; adults; site dep. on aetiology
Soft tissue: any age; any site; with syndromes
Histology:
multinodular, haemorrhagic, dissecting growth pattern
anything from well-formed vessels to solid sheets
often marked endothelial atypia and mitoses
CD31, CD34, Fli-1, Factor 8 variably positive

146. 18y old female patient, 5cm soft tissue tumour around the right ankle.
Case 7503/01:
18y old female patient, 5cm soft tissue tumour around the right ankle.

147. Case 7503/01

148. Case 7503/01

149. Case 7503/01

150. Case 7503/01 S100

151. Clear Cell Sarcoma
Soft tissue sarcoma with melanocytic differentiation
Young adults; deep-seated in extremities; slow growth
Histology:
nested and fascicular architecture
polygonal and spindle-shaped cells
wreath-like giant cells
low mitotic rate
S100 and melanocytic markers positive
Genetics: t(12;22)(q13;q12)

152. Case 24689/09:
64y old male patient, 2cm tumour medial aspect left wrist associated with tendon sheath.

153. Case 24689/09

154. Case 24689/09

155. Case 24689/09 CK
EMA

156. Case 24689/09 CD34

157. Epithelioid Sarcoma Distinctive sarcoma with epithelioid morphology
Classic type: years; hands, forearms, lower legs, feet
Proximal type: older age; pelvis, perineum, genital tract; aggressive
Histology:
multinodular, central necrosis
large epithelioid cells with eosinophilic cytoplasm, vesicular nuclei, small nucleoli
CK-profile (8,18,19), EMA, vimentin, CD34
DD: carcinoma, granuloma annulare, rheum. nodule

158. Minimum Dataset Soft Tissue Sarcomas
Clinical: site, depth from surface
Trimming:
one block per 10mm tumour, max. 12 blocks
sample margins <30mm (exceptions)
sample fat in retroperitoneal/abdominal/scrotal sarcomas
IHC: Ki67, myogenic differentiation
Genetic data
Report: type/subtype, grade (FNCLCC), margins, tissue planes involved, maximum size

159. Finally – the End!