Michael G. Rock

Extra-abdominal desmoid tumors.

One hundred and ninety-four patients with extra-abdominal desmoid tumors, most of them in the extremities, have been treated at the Mayo Clinic. One hundred and thirty-two patients (68 per cent) experienced a recurrence at an average of 1.4 years after the first treatment. A greater tendency for recurrence was evident in female patients, in patients who were more than thirty years old, in certain anatomical locations (especially the foot and calf), and most importantly after treatment by intralesional or marginal excision. In view of the excellent prognosis for survival, we recommend wide local excision when anatomically feasible or marginal excision and postoperative radiation therapy when function of the extremity would be severely compromised if excision with wide margins were done. A recurrent lesion that does not appear to be growing should be followed until evidence of growth of the lesion precipitates a secondary wide excision.

Metastases from histologically benign giant-cell tumor of bone.

Metastasis from a giant-cell tumor of bone that is histologically benign has become a recognized entity. To date, thirty-one pathologically proved cases have been reported in the world literature. To this, we add eight cases from our experience of more than 400 cases of histologically benign giant-cell tumor of bone. The lungs are the principal site of metastasis, the lesions being pathologically indistinguishable from the primary tumor. The metastatic process is unpredictable as to clinical aggressiveness, and the mortality rate is approximately 25 per cent. We advise aggressive attempts at complete extirpation of metastases.

Chondromyxoid fibroma of bone: A clinicopathologic review of 278 cases

In a study of the clinical, radiographic, and pathological features of chondromyxoid fibroma, the tumor was slightly more common in men, usually in the second decade of life. Almost half of the tumors involved the long bones, although the ilium and the small bones were also common sites. Roentgenograms showed a sharply marginated, lobulated, lucent defect in the metaphysis. The tumor involved the medullary bone in an eccentric fashion, and the cortex was thinned and expanded. Periosteal reaction and soft tissue extension were uncommon. Mineralization was identified in 13% of the lesions. Histologically, the tumors were almost always arranged in lobules, which were prominent (macrolobular) or somewhat indistinct (microlobular). The tumor cells were spindle-shaped or stellate and arranged in a myxoid matrix. Calcification was seen in more than one third of the cases but was rarely prominent. Hyaline cartilage and chondroblastoma-like areas were not uncommon. Approximately 18% of tumors showed bizarre nuclei. Permeation of bony trabeculae was uncommon. Treatment was conservative surgical removal; approximately one fourth of the patients had recurrence.

Giant-cell tumour of bone metastasising to the lungs: A LONG-TERM FOLLOW-UP

We reviewed 23 patients with a giant-cell tumour (GCT) of bone and histologically-proven lung metastases at a mean of 11.9 years (3 to 24.5) after the original diagnosis. The mean age of the patients at diagnosis was 27.3 years (9 to 61); the male to female ratio was 0.9:1. The most common primary site was the distal radius. The mean interval between the onset of the tumour and the detection of lung metastases was 4.1 years (0 to 24). There had been local recurrence in 19 (83%) either before or at the time of diagnosis of lung metastasis. Surgical resection alone was the preferred treatment for lung metastases in 70% and resulted in 18 patients (76%) being free from disease when last reviewed. One patient had the spontaneous regression of lung metastases and was free from recurrence 16 years later. Sixteen patients (69.7%) have survived and four (17.4%) have died from progression of the tumour. Three other deaths were not related to the tumour. Local recurrence and a primary lesion at the distal radius seem to be associated with an increased risk of lung metastases. Repeated surgical resection of lung metastases gave a high rate of survival.

Giant-cell tumour of bone metastasising to the lungs: A long-term follow-up

We reviewed 23 patients with a giant-cell tumour (GCT) of bone and histologically-proven lung metastases at a mean of 11.9 years (3 to 24.5) after the original diagnosis. The mean age of the patients at diagnosis was 27.3 years (9 to 61); the male to female ratio was 0.9:1. The most common primary site was the distal radius. The mean interval between the onset of the tumour and the detection of lung metastases was 4.1 years (0 to 24). There had been local recurrence in 19 (83%) either before or at the time of diagnosis of lung metastasis. Surgical resection alone was the preferred treatment for lung metastases in 70% and resulted in 18 patients (76%) being free from disease when last reviewed. One patient had the spontaneous regression of lung metastases and was free from recurrence 16 years later. Sixteen patients (69.7%) have survived and four (17.4%) have died from progression of the tumour. Three other deaths were not related to the tumour. Local recurrence and a primary lesion at the distal radius seem to be associated with an increased risk of lung metastases. Repeated surgical resection of lung metastases gave a high rate of survival.

Secondary malignant giant-cell tumor of bone. Clinicopathological assessment of nineteen patients.

Twenty-six patients who had a malignant giant-cell tumor of bone--a sarcoma either juxtaposed to a zone of typical benign giant-cell tumor or occurring at the site of a previously documented benign giant-cell tumor--have been seen at the Mayo Clinic. Of the twenty-six tumors, nineteen were secondary to a previous attempt at local control of a benign giant-cell tumor. All but one of these nineteen patients with a secondary tumor had received therapeutic irradiation four to thirty-nine years earlier. The nature and duration of the symptoms and the sites of predilection of the malignant giant-cell tumors were the same as for benign giant-cell tumor. Fibrosarcoma occurred three times as frequently as osteosarcoma. The best results of treatment of the secondary sarcoma were obtained with early ablation.

Extraskeletal Myxoid Chondrosarcoma: A Clinicopathologic, Immunohistochemical, and Ploidy Analysis of 23 Cases

Twenty-three cases of extraskeletal myxoid chondrosarcoma, evaluated at the Mayo Clinic between 1968 and 1996, were studied for clinicopathologic features, immunohistochemical profile, Ki-67 activity, and ploidy status to identify adverse prognostic factors. Females and males were equally affected, and the median age at diagnosis was 50 years. The tumors were located mainly in the lower extremities (83%), and the median tumor size was 9.5 cm. Sixteen tumors showed low cellularity (70%), and eight tumors had high mitotic activity (more than two per 10 high-power fields). The tumors were immunoreactive for vimentin (89%), synaptophysin (72%), epithelial membrane antigen (28%), and S-100 protein (17%). Nine tumors were diploid, three aneuploid, and one tetraploid. Mean Ki-67 activity was 11% (range, 1 to 45%). The 10-year overall survival rate was 78%. On univariate analysis, tumor size ≥ 10 cm, high cellularity, presence of anaplasia or rhabdoid features, mitotic activity more than two per 10 high-power fields, Ki-67 ≥ 10%, and Ki-67 “hot spot” ≥ 25% were associated with decreased metastasis-free or overall survival. Ploidy status was not associated with any adverse outcome. The presence of any of these adverse prognostic factors can indicate the possibility of a more aggressive behavior in extraskeletal myxoid chondrosarcoma, and a closer follow-up is suggested.

Megaprostheses after resection of distal femoral tumors: A rotating hinge design in 30 patients followed for 2-7 years

Between 1981 -1 993, we inserted 32 Kinematic Rotating-Hinge Knee tumor prostheses in 30 patients, of which 2 concerned revisions of the same type of prosthesis. The diagnoses were 21 osteosarcomas, 2 chondrosarcomas, 2 Ewings sarcomas, 2 metastatic breast carcinomas, l multiple myeloma, l giant cell tumor and 1 Gorhams disease. The median age was 25 (1 2-60) years and the median follow-up for survivors was 3.5 (2-6.6) years. There were 7 metastases and 1 local recurrence.20 knees had excellent (MSTS) scores for motion (median flexion 1 20°), 8 had good (84O) and 4 had fair (459. The overall function was excellent in 6 cases, good in 14, fair in 9 and poor in 3. The radiographic assessment (ISOLS) gave “excellent” or “good” scores in 27 knees for bone remodelling, 31 for the interface, 28 for anchorage, 31 for the implant body and 30 for the articulation. Extracortical bone bridging greater than 25% was observed in 18 of 27 prostheses.

Solitary bony metastasis from renal cell carcinoma: significance of surgical treatment.

To define the importance of the type of surgical treatment, we retrospectively analyzed the survival rate of 60 patients with solitary bony metastasis from renal cell carcinoma. Thirteen patients had wide resection, 20 had local stabilization, and 27 patients had no surgical treatment, but had adjuvant treatment alone. The 1-, 3-, and 5-year survival rates were 83%, 45%, and 23%, respectively. Patients with surgical treatment (wide or intralesional resection) survived longer compared with patients who had no surgical treatment but had adjuvant treatment modalities. However, there was no survival advantage for patients who had a wide resection of the lesion compared with patients who had intralesional resection or intramedullary stabilization alone. Our results indicate that wide surgical excision of a solitary bony metastasis from renal cell carcinoma is not mandatory to improve survival. However, because three of 20 patients (15%) treated with stabilization alone had local disease progression, wide resection of metastatic lesions and stabilization may be necessary to prevent local disease progression and complications. Level of Evidence: Therapeutic study, Level IV (case series—no, or historical control group)

Segmental total knee arthroplasty after distal femoral resection for tumor

Sixty-one patients treated with custom-made segmental total knee reconstruction after resection of a primary tumor of the distal femur were reviewed retrospectively. Two types of implants were used: the Walldius hinge prosthesis (Walldius Group, n = 45) and the Kinematic rotating hinge prosthesis (Kinematic Group, n = 16). The mean periods of follow-up observation were 6.4 years for the Walldius Group and 2.3 years for the Kinematic Group. The overall functional results in the Walldius Group were excellent in 7%, good in 26%, fair in 25%, and poor in 42% of the patients. Roentgenographic analyses showed that 50% of the patients had bony resorption, 33% had interface loosening, and 10% had prosthetic stems that were broken at the time of last follow-up evaluation. Forty-two complications occurred in 34 patients who needed additional surgical treatment. Nine of the prostheses in the Walldius Group failed (20%), and 27 of the complications (64%) associated with the use of the Walldius prosthesis occurred in the first three years after implantation. Nineteen Walldius prostheses (42%) were revised or removed for reasons other than local recurrence. The overall functional results of the Kinematic Group were as follows: excellent in 25%, good in 44%, fair in 25%, and poor in 6% of the patients. Roentgenographic analysis showed that there was no change in bone on 81% of the discharge roentgenograms, that there were no radiolucent lines in 87% of the prosthetic replacements, and that there were no radiolucent lines less than 2 mm thick on the roentgenograms. None of the Kinematic rotating hinge prostheses required revision, except one with a patellar button fracture, which was revised without compromising the functional results. Four complications occurred in three patients in the Kinematic Group, and two of them required surgical treatment. The patients with the Kinematic rotating hinge prosthesis had better early functional and roentgenographic results and fewer complications.