Osteosarcoma Resembling Osteoblastoma

FRANC0 BERTONI, MD,’ KRISHNAN K. UNNI, MB, BS,t RICHARD A. MCLEOD, MD,$ AND DAVID C. DAHLIN, MDt

A series of 17 patients with osteosarcomas that histologically resembled osteoblastomas was studied. The ages of the 9 male and 8 female patients ranged from 11 to 58 years. The roentgenographic appearance was suggestive of malignancy in most cases. Two histologic features seemed most important in differentiating osteosarcoma from osteoblastoma. In the former, there is permeation of surrounding tissues and lack of “maturation” toward the edges, whereas osteoblastoma tends to show maturation peripherally and is circumscribed. Osteoblastoma-like osteosarcoma should be considered to be a malignant tumor because 7 of the 17 patients died of their disease. The authors believe that malignant osteoblastoma and aggressive osteoblastoma are really osteosarcomas that resemble osteoblastomas.

Cancer 55416-426, 1985.

STEOBLASTOMA is generally considered to be the 0 benign counterpart of osteosarcoma. Although they probably are unrelated conditions, osteoblastoma has been reported to undergo malignant trans-

and for some tumors, the question of “benign” versus “malignant” is difficult to a n ~ w e r . ~ , ~ This problem has been previously addressed under the terms “malignant oste~blastoma”~~~ and “aggressive 0steob1astoma.”~- We have reviewed our experience with 17 cases in which the differential diagnosis was between osteoblastoma and osteosarcoma.

Materials and Methods Slides from more than 1200 osteosarcomas in the

Mayo Clinic files were reviewed. In addition, all consul- tation cases in which a diagnosis of low-grade osteosar- coma and osteosarcoma resembling osteoblastoma was rendered were reviewed. Seventeen cases of well-differ- entiated osteosarcomas that resembled osteoblastomas were identified: 5 from the Mayo Clinic files and 12 from the consultation files. The ordinary osteoblastomas were not reviewed because they did not pose a significant problem in differential diagnosis. Of the 17 patients, 9 were males and 8 were females, with ages ranging from 1 1 to 58 years (Table 1). Preoperative roentgenogramsof 13 patients were available, and follow-up information was obtained from clinic charts and the referring physi- cians.

From the Departments of ?Surgical Pathology and .$Diagnostic Ra- diology, Mayo Clinic and Mayo Foundation, Rochester, Minnesota.

* Visiting Surgical Pathologist from USL 28 Ospdale M. Malpighi, Servizio di Anatomia ed Istologia Patologica, and the Rizzoli Institute, Bologna, Italy.

Address for reprints: Krishnan K. Unni, MB, BS, Mayo Clinic, 200 First Street SW, Rochester, MN 55905.

Accepted for publication January 16, 1984.

Results

Clinical Findings

Most patients presented with pain, usually of short duration. Four tumors involved the tibia, three the ver- tebrae, two the sacrum, two the fibula, and one each the scapula, cuboid, femur, ilium, maxilla, ethmoid, and temporal bone (Fig. 1); one patient had two tumors.

Roentgenographic Findings Roentgenograms were available for study in 13 cases.

The appearances at presentation varied. Malignancy was correctly suggested in 9 of the 13

cases. Ossification was present in six of the nine malig- nant-appearing lesions, allowing the radiologist to cor- rectly suggest a diagnosis of osteosarcoma (Figs. 2A and 2B, and Fig. 3). The other three lesions were purely lytic and, though malignant in appearance, were otherwise nonspecific in presentation. One tumor that was consid- ered an osteosarcoma had an equivocal appearance, and

15 -

10 - No of cases

5 -

n - -

17 Patients--18 tumors

Males 9 Females 8 Total 17

1 1

2 i I . . . . . .

2 ’I 10 20 30 40 50 60 70

Age In decades

FIG. 1. Age of patients and skeletal distribution of osteosarcomas.

416

No. 2 OSTEOSARCOMA RESEMBLING OSTEOBLASTOMA Bertoni et al. 417

FIGS. 2A AND 2B. Osteosarcoma of femur. (A, left) Anteroposterior and (B, right) lateral views show classic presentation of osteosarcoma.

osteoblastoma had to be considered in the differential diagnosis (Figs. 4A and 4B).

In 4 of the 13 cases, the roentgenographic appearance erroneously indicated a benign lesion. In three, osteo- blastoma was the suggested diagnosis (Fig. 5 ) , while in one, the tumor was considered to be a typical osteoid osteoma (Figs. 6A and 6B). One tumor believed to be an osteoblastoma was considered to have a borderline ap- pearance, and osteosarcoma had to be included in the differential diagnosis (Fig. 7 ) .

Gross Appearance

0n:ly two specimens had gross features that could be evaluated: one from the ethmoid and one from the ilium. Neither had the “fish-flesh” appearance of con- ventional osteosarcoma. The specimen from the eth-

FIG. 3. Osteosarcoma of ilium. CT scan shows features typical of osteosarcoma, with large partially ossified soft tissue mass on either side of ilium.

maid was red and granular, and the lesion from the was markedly cystic.

f

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Mid

thig

h am

puta

tion

(lytic

def

ect

Die

d, M

ay 1

963

(8 m

o),

R fib

ula,

upp

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nd

(9-2

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tal

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puta

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raph

ic.

420 CANCER January I5 1985 Vol. 5 5

No. 2 OSTEOSARCOMA RESEMBLING OSTEOBLASTOMA Bertoni et al. 42 1

Microscopic Appearance

The tumors were selected primarily because of their resemblance to osteoblastomas. The tumors were found to permeate bone, particularly when the material for review included the edge of the tumor (Figs. 8A and 8B). Under low-power microscopy, abundant bone produc- tion was evident as well-formed bony trabeculae (Fig. 8C). Trabeculae were rimmed with plump cells that had eosinophilic cytoplasm and round nuclei. The nuclei usually had prominent nucleoli, and the cells had pink cytoplasm, making them appear to be “epithelioid” (Fig. 8D). Mitotic figures were abundant. In addition to rim- ming the bony trabeculae, the tumor cells were present between the trabeculae, giving the lesion a cellular ap- pearance (Fig. 8D). In addition, some of the tumors showed areas that were more typical of conventional osteosarcomas, having small inconspicuous cells in a heavily ossified matrix or having spindle cells with lace- like osteoid.

Treatmenl and Survival

Because the study is retrospective, our definitions of the treatment modalities employed are arbitrary. We have no information about the treatment of three pa- tients (Cases 5 , 7, and 8) (Table l).

Of the 1 1 patients who underwent excision primarily, 1 (Calse 6) received postoperative radiotherapy and was alive without disease at 1 I months, at which time she was lost to follow-up. Three of the other 10 patients under- went amputation for recurrent tumor. Two (Cases 9 and 1 1 ) of the three patients were alive without disease, one 2 years, and the other 3 years later. The third patient (Case 1) died 8 months after amputation, with metastasis to the lungs and bones. The remaining seven patients were treatled with combinations of surgery, radiotherapy, and chemotherapy. Two (Cases 4 and 12) of the seven were alive without disease at last follow-up (2 and 3 months, respectively), and the other five (Cases 2, 3, 10, 13, and 16) were dead or dying 6 ,7 , 10,3, and 5 months, respec- tively, after the last treatment, with local extension ofthe tumor in three, lung metastasis in one, and local exten- sion and lung and brain metastasis in one.

Of the other three patients, one (Case 14) received radiotherapy after biopsy and was given chemotherapy after pulmonary metastasis was detected. She died 13 months later of disease. One patient (Case 17), with a maxillary lesion, underwent maxillectomy and was alive without disease at 19 months. A third patient (Case 15) underwent hemipelvectomy for an iliac lesion. Fifteen months later, she had resection of multiple metastatic lesions in the lung and was alive 6 months later with no progression of disease.

FIG. 5. Osteosarcoma of tibia. Roentgenographic appearance sug- gestive of osteoblastoma.

In summary, 7 of the 17 patients are known to have died of the tumor and 7 have survived; however, the longest follow-up was only 3 years.

Discussion

We have been impressed with the rare case in which the differentiation of osteosarcoma from osteoblastoma was difficult. The problem seems to be most common with spinal lesions.

The 17 cases in this series were chosen on the basis of the histologic appearance of the lesion, that is, osteosar- coma that resembled osteoblastoma on low-power mi- croscopic examination. In the past, this problem has been addressed under the terms “aggressive osteoblas- toma”’ and “malignant osteoblastoma.”8

We recognized only 5 such cases in the Mayo Clinic files, which include more than 1200 osteosarcomas, in-

422 CANCER January 15 1985

i 8 8 c

9

8 0 0 c

Vol. 55

No. 2 OSTEOSARCOMA RESEMBLING OSTEOBLASTOMA Bertoni et al. 423

dicatiing the rarity of this problem. Their relative abun- dancle in the consultation files attests to the difficulty in diagnosing them.

The clinical features are not remarkable except for the relatively high incidence in the vertebral column ( 5 / 17), including the sacrum. This incidence is higher than for conventional osteosarcoma.

A roentgenographic presentation that is typical of ma- lignancy or shows the classic features of osteosarcoma is quite useful (8/ 13). However, some tumors are initially seen with an equivocal roentgenographic picture of os- teosarcoma versus typical osteoblastoma (2/ 13). The roentgenographic appearance may be misleading when typical of a benign process (3/ 13). This difficult problem is further complicated because about 25% of osteoblas- tomas initially have a roentgenographic appearance sug- gestive of malignancy.12

The gross appearance also does not appear to be help- ful. The typical osteosarcoma is white and fleshy, whereas the typical osteoblastoma is red and granular. However, osteoblastoma-like osteosarcomas are also red and granular. Thus, the distinction probably has to be made on histologic findings alone. The distinguishing features that we believe are helpful are given in Table 2. Two of these features are most useful. First, the edge of osteoblastoma will tend to show maturation or zonation - thlat is, the presence of peripheral, well-formed bony trabeculae - whereas the edge of the osteoblastoma ap- pears to be well-rounded, with no tendency for the tumor to permeate the surrounding bone (Fig. 9A). Second, the inteitrabecular tissue of an osteoblastoma is loose and vascular (Fig. 9B), whereas that of an osteosarcoma is solicl and cellular (Fig. 8D).

The differential diagnosis is impossible to make with limited tissue, for example, from a needle biopsy, and may be impossible even with adequate tissue.

Two rare variants of osteoblastoma have to be consid- ered in the differential diagnosis: pseudomalignant os- teoblastoma and multifocal osteoblastoma. Pseudoma- lignant oste~blastoma~~ has bizarre cells similar to those seen in neurilemmoma. However, the cells do not show

FIG. 7. Osteosarcoma of tibia. Sharp margin and sclerotic rim favor diagnosis of osteoblastoma. Osteosarcoma included in differential diagnosis because of cortical destruction.

mitotic activity (Figs. 1OA and IOB). Such bizarre cells are not seen in osteoblastoma-like osteosarcomas. Mul- tifocal osteoblastoma has multiple small foci of osteo- blasts that permeate reactive bone and produce a large total mass. However, the foci appear to be in the inter- trabecular spaces and do not destroy tissue. They are not apposed to the trabeculae and, hence, do not appear to

TABLE 2. Differential Histologic Features of Osteoblastoma and Osteoblastoma-Like Osteosarcoma

Feature Osteoblastoma Osteosarcoma

Cytoairchitectural organization Trabeculae of osteoid rimmed by osteoblasts; spindle cells, osteoclasts, and capillary vessels between trabeculae

Mitolic rate Generally low Atypical mitosis No Zonal phenomenon Yes Permeating bone growth Margins Well defined Sheets of cells without bone production

No; sometimes multifocal

No

Large cells with abundant deep-staining cyto- plasm, large nucleus with big nucleolus, and osteoclasts may be present between trabecu- lae of osteoid

Generally high May be present No Yes Permeation and infiltration Yes

424 CANCER January 15 1985 Vol. 55

FIGS. 8A-8D. Osteosarcoma simulating osteoblastoma. (A, top left) Edge of tumor is irregular, with destruction of bone (H & E, original magnification X 5). (B, top right) Permeation between bone trabeculae at edge (H & E, original magnification X 250). (C, bottom left) Low power shows pattern of osteoblastoma (H & E, original magnification X 64). (D, bottom right) Higher power shows the plump cells and lack of vascularity (H & E, original magnification X 250).

FIciS. 1 OA AND 10B. Osteoblastoma with bizarre nuclei. Nuclear details are blurred, and cells are similar to those seen in “chemotherapy” effect (H & E, original magnification X 250).

426 CANCER January 15 1985 VOl. 55

permeate bone, as do the foci of osteoblastoma-like os- teosarcoma.

We prefer to think of the lesions as osteosarcomas. We believe that the lesion we refer to as osteoblastoma-like osteosarcoma is identical to that described by Schajo- wicz and Lemos7s8 as malignant osteoblastoma and by Dorfman1p9 as aggressive osteoblastoma. Whatever the term used, it is important to recognize this small group of osteoblast-rich lesions that resemble osteoblastomas but behave like osteosarcomas.

ADDENDUM

After this manuscript was submitted, we learned that Case 9 was reportedI4 as osteoid osteoma transforming to an aggressive (low-grade malignant) osteoblastoma.

REFERENCES 1. Dorfman HD. Malignant transformation of benign bone lesions.

Proc Natl Cancer Conf 1972; 7:901-913. 2. Mayer L. Malignant degeneration of so-called benign osteoblas-

toma. Bull Hosp Joint Dis 1967; 28:4- 13. 3. Merryweather R, Middlemiss JH, Sanerkin NG. Malignant

transformation of osteoblastoma. J Bone Joint Surg [Br] 1980;

4. Seki T, Fukuda H, Ishii Y et al. Malignant transformation of 62:381-384.

benign osteoblastoma: A case report. J Bone Joint Surg [Am] 1975;

5. Dahlin DC. Bone Tumors: General Aspects and Data on 622 1 Cases, ed. 3. Springfield, IL: Charles C Thomas, 1978; 283.

6. Jackson JR, Bell MEA. Spurious “benign osteoblastoma”: A case report. J Bone Joint SurgIAm] 1977; 59:397-401.

7. Schajowicz F, Lemos C. Osteoid osteoma and osteoblastoma: Closely related entities of osteoblastic derivation. Acta Orthop Scund

8. Schajowicz F, Lemos C. Malignant osteoblastoma. JBone Joint

9. Dorfman HD. Case records ofthe Massachusetts General Hospi-

10. Revell PA, Scholtz CL. Aggressive osteoblastoma. J Pathol

11. Spjut HJ, Fechner RE, Ackerman LV. Tumors of bone and cartilage. In: Hartmann WH, ed. Atlas of Tumor Pathology, series 2, fascicle 5, supplement. Washington D.C.: Armed Forces Institute of Pathology, 198 I .

12. McLeod RA, Dahlin DC, Beabout JW. The spectrum of osteo- blastoma. Am JRoentgenol 1976; 126:321-335.

13. Mirra JM, Kendrick RA, Kendrick RE. Pseudomalignant os- teoblastoma versus arrested osteosarcoma: A case report. Cancer 1976;

14. Pieterse AS, Vernon-Roberts B, Paterson DC et al. Osteoid os- teoma transforming to aggressive (low grade malignant) osteoblas- toma: A case report and literature review. Histopathology 1983;

57~424-426.

1970 41:272-291.

Surg[Br] 1976; 58:202-21 I .

tal (Case 40-1980). N Engl JMed 1980; 303:866-873.

1979; 127~195-198.

37~2005 - 201 4.

7 :789 - 800.

American Board of Internal Medicine 1985 Subspecialty Examination in Medical Oncology

Registration period: January I , 1985-April I , 1985

Examination date: November 19, 1985

Physicians certified in internal medicine who completed 2 years of acceptable subspecialty training in hematology, medical oncology, or hematology/oncology in June 1975 or before will fullfill the Board’s training requirements for admission to the examinations in Hematology and Medical Oncology only through 1986. Therefore, such Diplomates must be admitted to the 1985 Medical Oncology or to the 1986 Hematology Examination to achieve certification in both subspecialties. After these examinations, all candidates must have had at least 3 years of acceptable training to be certified in both subspecialties.

For further information and application forms please contact: American Board of Internal Medicine, 3624 Market Street, Philadelphia, PA 19104 (215) 243-1500.

(Note: Examination date has been changed from November 12, 1985)