THE AMERICAN JOURNAL OF CLINICAL PATHOLOGY
Vol. 51, No. 2
Copyright © 1909 by The Williams & Wilkins Co.
Printed in U.S.A.
FASCIITIS OSSIFICANS
JOHN KWITTKEN, M.D., AND MATTHEW BRANCHE, M.D.
Departments of Pathology and Surgery, Knickerbocker Hospital, New York, New York 100S7
Mesodermal proliferations appearing to be
malignant histologically but behaving benign
clinically are well documented. Included in
this category are such entities as atypical
fibroxanthoma, pseudosarcomatous fibromatosis (nodular fasciitis), and proliferative
myositis. Similar lesions occurring within or
about skeletal muscle associated with the
formation of bone have been termed myositis
ossificans. The authors wish to report a case
with the lesion confined to the subcutaneous
fascia in which giant cells and ossification
were conspicuous features.
REPORT OF A CASE
A 24-year-old Negro male was admitted to
Knickerbocker Hospital on April 4, 1965,
because of a "hard lump" on his right thigh,
of approximately 2 months' duration.
Physical examination revealed a firm, nontender, smooth-contoured, ovoid, slightly
mobile, subcutaneous mass, 3.0 cm. in
maximal diameter, located 9.5 cm. from the
lateral epicondyle of the femur on the
posterolateral aspect of the right thigh.
There was slight elevation of the overlying
skin which was smooth, darkened, and
partially fixed to the underlying tumor.
Between 1958 and 1963 the patient had a
job which consisted primarily of moving
cartons. On occasion, these cartons would
strike the lateral aspect of the right thigh.
There was never any physical or clinical
evidence of injury, however. He had never
received any injections in the right thigh.
The remainder of the history was noncontributo ry.
A complete blood count, hemoglobin
determination, urinalysis, and serum alkaline phosphatase were normal. A skeletal
survey was entirely negative except for
severe dorsolumbar scoliosis.
On April 5,1965, under general anesthesia,
Received May 6, 1968.
the mass was excised in loto with a rim of
normal, subcutaneous, fibrous and adipose
tissue. The tumor, which measured 5.0 by
4.5 by 3.0 cm. in maximal dimensions, was
confined to the subcutaneous fascia (tela
subcutanea) and appeared to be well demarcated from the surrounding tissue. I t
presented grayish brown, fleshy, cut surfaces
with scattered foci of recent-hemorrhage, as
seen in Figure 1.
Microscopically, the mass was separated
from the surrounding corium and subcutaneous tissue by broad bands of dense
fibrous tissue which also extended into the
tumor, dividing it into coarse lobules. Upon
cursory examination, the histologic features
appeared disorderly. However, after study,
we were able to detect a systematic growth
pattern which, in our opinion, appeared to
develop chronologically along two separate
lines. The earliest change, common to both
lines of development, was composed of a
loose, interlacing network of spindle-shaped
cells admixed with small numbers of multinucleated giant cells of the foreign-body
type, and abundant inflammatory cells
composed of lymphocytes, segmented neutrophils, plasma cells, and macrophages. This
change is shown in Figure 2. The intervening
stroma was edematous and composed of
numerous thin walled blood vessels. In
many foci, extravasations of red blood cells
were observed. The spindle-shaped cells
varied considerably in size and their nuclei
exhibited frequent pleomorphism, hyperchromatism, and mitoses. In many areas, it
was possible to discern the development of
multinucleated giant cells from these spindleshaped cells. The giant cells, therefore,
varied considerably in size, containing from
only a few to several dozen nuclei. Their
nuclei were generally round, uniform, and
vesicular, with a prominent central nucleolus.
Often, however, their nuclei exhibited striking variations in size, pleomorphism, hyperchromatism, and mitoses.
251
252
KWITTKEN AND BKANCHE
The remainder of the histologic picture
appeared to depend upon the predominant
direction of differentiation of these spindleshaped cells. These cells seemed to differentiate into either multinucleated giant
cells or mature fibrous tissue with subsequent
ossification. In the case of the former, microscopic fields were observed containing
literally hundreds of multinucleated giant
cells with lesser amounts of the other cellular
elements, as described in the earliest change.
This is depicted in Figure 3. In the case of
the latter, one could find microscopic fields
showing successive stages in the development from immature into mature fibrous
tissue, with subsequent transformation of
the collagenized stroma first into osteoid
tissue and then into immature bone. This is
presented in Figures 4 through 7. It was
noteworthy that in these end stage processes
of fibrosis and ossification, nuclear atypism
and mitoses were practically nonexistent.
Special stains disclosed the presence of
abundant reticulin fibers about individual
giant and spindle-shaped cells, as revealed in
Figure S. A large amount of iron M'as noted
within macrophages throughout the tumor,
as may be observed in Figure 9. Only small
amounts of neutral fat and mucopolysaccharides (acid and neutral) could be detected
within some of the macrophages. No foreign
material could be identified within the
tumor.
There was excellent healing of the wound
postoperatively and the patient was discharged on April 15, 1965. Routine follow-up
on March 8, 1968, disclosed a well healed
vertical scar, 7.5 cm. in length, at the operative site. There was no underlying nodularity
or muscle atrophy. The lung fields were clear
and there was no peripheral lymphadenopathy.
Vol. 51
tumor of bone, giant cell tumor of tendon
sheath, myositis ossificans, and proliferative
myositis should be mentioned for the sake of
completeness but not truly considered in the
differential diagnosis. Furthermore, since
this lesion was biologically benign, even
though certain histologic features were
suggestive of malignancy, malignant tumors
such as metastatic giant cell tumor of bone,
metastatic osteogenic sarcoma, primary
extraskeletal osteogenic sarcoma, and malignant fibrous xanthoma need not concern us
diagnostically.
A foreign body granuloma can be excluded
on the basis of a negative history of injections in this area, the absence of foreign
material microscopically, and the presence
of atypical cellular features. Furthermore,
osteoid tissue and bone formation is seldom,
if ever, observed in a foreign body granuloma.
To label this lesion as an extraskeletal
giant cell tumor of soft tissue (osteoclastoma) analagous to those described in bone
would be fallacious. The majority of cases of
this rare lesion which have been reported
trace their origin to a bony structure. 8 In
our case, there was no preexisting bone in the
vicinity of the lesion. Moreover, bone
formation is not a characteristic feature of
the benign giant cell tumor such as occurs in
bone. 1 ' 4 AVhen it does occur, it is usually a
reactive change observed around the peripheral margins of the tumor as it extends
into soft tissue. In addition, a pseudosarco-
DISCUSSION
In the differential diagnosis, one should
consider a number of benign lesions such as
foreign body granuloma, giant cell tumor of
soft tissue (osteoclastoma), atypical fibroxanthoma, and pseudosarcomatous fibromatosis (nodular fasciitis). Inasmuch as
this lesion did not involve tendon sheaths, a
skeletal muscle, or bone, other benign conditions such as parosteal fasciitis,2 giant cell
FIG. 1. Well demarcated, ovoid, focally hemorrhagic, subcutaneous nodule. As can be seen, a
wedge has been previously removed from the tumor {left lower portion of photo).
Fio. 2 (upper left). Early change showing loose network with polymorphous cellular infiltrate. Note size variation of spindle-shaped cells as well as their composition, nuclear pleomorphism, and hj'perchromatism. A cell below center is seen in mitosis. Hematoxylin and
eosin. X 240.
Fio. 3 (upper right). Microscopic field containing numerous multinucleated giant cells of
varying sizes. Note frequency of irregular hyperchromatic nuclei and mitoses. Hematoxylin
and eosin. X 240.
FIG. 4 (lower left). Beginning fibroplasia. Hematoxylin and eosin. X 240.
FIG. 5 (lower right). Relatively advanced stage of fibrosis. Hematoxylin and eosin. X 240.
253
•^E
•i^
Fia. G (upper left). Formation of osteoid tissue. Hematoxylin and eosin. X 240.
FIG. 7 (upper right). Immature bone formation. Hematoxylin and eosin. X 120.
FIG. S (lower left). Abundant reticulin fibers are present about individual giant and spindle-shaped cells. Reticulum. X 120.
FIG. 9 (lower right). Numerous macrophages contain iron within their cytoplasm. Gomori's stain for iron. X 240.
254
Feb. 1969
255
FASCIITIS OSSIFICANS
matous microscopic pattern such as was observed in our case is not seen in the benign
giant cell tumor that occurs in bone.
Clinically and histologically the lesion in
our case does not fit the picture of atypical
fibroxanthomas of the skin.5 These lesions
generally present as ulcerated nodules of the
dermis occurring in the sun-damaged or
previously traumatized skin of elderly
persons. In our case, the lesion involved the
subcutaneous tissue of the sun-protected
skin without ulceration or definite evidence
of prior trauma in a young person. Also,
osteoid and osseous tissues have not been
described in atypical fibroxanthomas of the
skin.
Although the location of the lesion, as
well as its apparently short period of rapid
growth, would be consistent with that described in pseudosarcomatous fibromatosis,
the microscopic features are not. In the
first place, multinucleated giant cells are not
a constant or conspicuous feature of pseudosarcomatous fibromatosis.3'G' '• 9 i 10 Furthermore, when they are present, they generally
do not contain more than two to six nuclei,
they do not show atypical features, and they
rarely show mitotic activity. Second, osteoid
and osseous tissues are rarely found in
pseudosarcomatous fibromatosis.3, u When
they are observed, they are certainly inconspicuous features. Third, iron is rarely,
if ever, observed in pseudosarcomatous
fibromatosis.6'10
It is our opinion that the lesion under
discussion represents a reactive proliferation
of mesodermal tissues to a stimulus of
probable traumatic origin. Its pathogenesis
is therefore probably similar to that of
proliferative myositis, myositis ossificans,
atypical fibroxanthoma of the skin, and
pseudosarcomatous fibromatosis. To the best
of our knowledge, no similar case has been
reported. It is realized that the reader may
wish to consider this as an unusual variant
of one of the diseases mentioned above, instead of as a new and separate entity. This is
immaterial to us. It may well be a variant of
one of the aforementioned conditions. Whatever the case may be, it is important that
such cases be reported in order that lesions
like this one be recognized as benign so that
aggressive surgical procedures might be
avoided. Since we cannot see fit at this time
to classify it with these other reactive
mesodermal proliferations because of the
differences described, and in order to stress
the main histologic characteristics, we wish
to give it the appellation of fasciitis ossificans.
SUMMARY
The case of a 24-year-old Negro male
with a histologically malignant-appearing
mesodermal proliferation, limited solely to
the subcutaneous tissue, is reported. Its
histologic features are detailed and its
differentiation from the other clinically
benign, but microscopically malignantappearing, mesodermal lesions reported is
sufficient to warrant publication. Multinucleated giant cells of the foreign body type
and bone formation were conspicuous features. In order to emphasize its chief histologic features, we have named it fasciitis
ossificans. To the best of our knowledge, no
similar case has been previously reported.
Whether one chooses to consider this as a
variant of the mesodermal proliferations
previously reported or as a separate entity is
immaterial.
REFERENCES
1. Ackerman, L. V., and Spjut, H. J.: Tumors of
Bone and Cartilage, Sect. 2, Fase. 4. Washington, D. C : Armed Forces Institute of
Pathology, 19G2, pp. 201-205.
2. Hutter, R. V. P., Foote, F. W., Jr., Francis,
K. C, and Higinbotham, N. L.: Parosteal
fasciitis. Am. J. Surg., 104: SOO-807, 1062.
3. Hutter, R. V. P., Stewart, F. W., and Foote,
F. W., Jr.: Fasciitis. Cancer, 15: 992-1003,
1962.
4. JafTe, H. L.: Tumors and Tumorous Conditions of the Bones and Joints. Philadelphia: Lea & Febiger, 1958, pp. 18-43.
5. Kcmpson, R. L., and McGavran, M. H.:
Atypical fibroxanthomas of the skin. Cancer, 17: 1403-1471, 1904.
G. Konwaler, B. E., Keasbey, L., and Kaplan,
L.: Subcutaneous pseudosarcomatous fibromatosis (fasciitis). Am. J. Clin. Path.,
25: 241-252, 1955.
7. Price, E. B., Jr., Silliphant, W. M., and Shuman, R.: Nodular fasciitis: a clinicopathologic analysis of 65 cases. Am. J. Clin.
Path., 35: '122-136, 1961.
8. Schmaman, A., Penn, I., and Sorour, V.:
Giant-cell tumours of the soft tissues.
South African M. J., 37: S19-S20, 1963.
9. Schreiber, M. M., Shapiro, S. I., and Sampsel, J.: Pseudosarcomatous fibromatosis
(fasciitis). Arch. Dermat., 92: 661-665,
1905.
10. Soûle, E. H.: Proliferative (nodular) fasciitis.
Arch. Path., 73: 437-444, 1962.
11. Stout, A. P.: Pseudosarcomatous fasciitis
in children. Cancer, 14: 1216-1222, 1961.