Suzanne B. Keel

Chondrosarcoma of the base of the skull : A clinicopathologic study of 200 cases with emphasis on its distinction from chordoma

Conventional chondrosarcoma (CSA) of the skull base is an uncommon neoplasm that can resemble chordoma, and indeed it is misdiagnosed frequently as such. This has important clinical implications, because when treated with similar aggressive treatment strategies, CSA has a much better prognosis than chordoma. In an effort to identify those morphologic and immunohistochemical features that help to identify conventional skull base CSA correctly and to understand its prognosis better, particularly compared with chordoma, when treated with surgery and proton beam irradiation, the authors performed a clinicopathologic analysis of 200 CSAs. The patients ranged in age from 10 to 79 years (mean, 39 years), 87 patients were male and 113 patients were female, and most presented with symptoms related to the central nervous system. Approximately 6% of the tumors arose in the sphenoethmoid complex, 28% originated in the clivus, and 66% developed in the temperooccipital junction. Histologically, 15 tumors (7.5%) were classified as hyaline CSA, 59 (29.5%) as myxoid CSA, and 126 (63%) as mixed hyaline and myxoid CSA. A total of 101 (50.5%) tumors were grade 1, 57 (28.5%) had areas of grades 1 and 2, and 42 (21%) were pure grade 2 neoplasms. The vast majority of patients originated from referring hospitals, and the diagnosis was changed prospectively at our institution to CSA from chordoma in 74 patients (37%). Of the tumors studied immunohistochemically, 96 of 97 (98.9%) stained for S-100 protein, 0 of 97 (0%) stained for keratin, and faint staining for epithelial membrane antigen was seen in 7 of 88 tumors (7.95%). All patients underwent high-dose postoperative fractionated precision conformal radiation therapy with a dose that ranged from 64.2 to 79.6 Cobalt-Gray-equivalents (median, 72.1 Cobalt-Gray-equivalents, given in 38 fractions. The 200 patients had a median follow-up of 63 months (range, 2.1 mos - 18.5 yrs). Tumor control was defined as lack of progression by clinical and radiographic assessment. Based on this definition, there were three local recurrences, and two of these patients died of tumor-related complications. The 5- and 10-year local control rates were 99% and 98% respectively, and the 5- and 10-year disease-specific survival rates were both 99%. In contrast to CSA, the 5- and 10-year survival rates of chordoma have been reported to be approximately 51 % and 35% respectively, and in our institution intensive treatment has resulted in 5- and 10-year progression-free survival rates of 70% and 45% respectively. CSA of the skull base can be distinguished reliably from chordoma, and this distinction is important because skull base CSA has an excellent prognosis when treated with surgery and proton beam irradiation, whereas chordomas have a substantially poorer clinical course despite similar aggressive management.

Lipoma arborescens of the knee

Lipoma arborescens is a rare intra-articular lesion, characterised by diffuse replacement of the subsynovial tissue by mature fat cells, producing prominent villous transformation of the synovium. The aetiology of this benign condition is unknown. We describe six cases involving the knee, discussing the symptoms, diagnosis and treatment.

Orthopaedic implant-related sarcoma: a study of twelve cases.

Sarcoma developing in association with a metallic orthopaedic prosthesis or hardware is an uncommon, but well recognized complication. We review 12 cases of sarcomas arising in bone or soft tissue at the site of orthopaedic hardware or a prosthetic joint. Nine patients were male, and three were female. Their ages ranged from 18 to 85 (mean 55) years at the time of diagnosis of the malignancy. Five patients had undergone hip arthroplasty for degenerative joint disease, four had been treated with intramedullary nail placement for fracture, two had staples placed for fixation of osteotomy, and one had hardware placed for fracture fixation followed years later by a hip arthroplasty. The time interval between the placement of hardware and diagnosis of sarcoma was known in 11 cases and ranged from 2.5 to 33 (mean 11) years. The patients presented with pain, swelling, or loosening of hardware and were found to have a destructive bone or soft tissue mass on radiography. Two sarcomas were located primarily in the soft tissue and 10 in bone. Seven patients developed osteosarcoma, four malignant fibrous histiocytoma, and one a malignant peripheral nerve sheath tumor. All sarcomas were high grade. Three patients had metastatic disease at the time of diagnosis. Follow-up was available on eight patients: five patients died of disease 2 months to 8 years (mean 26 months) after diagnosis; two patients died without evidence of disease 7 and 30 months after diagnosis; and one patient is alive and free of disease 8 years after diagnosis. Sarcomas that occur adjacent to orthopaedic prostheses or hardware are of varied types, but are usually osteosarcoma or malignant fibrous histiocytoma. They behave aggressively and frequently metastasize. Clinically, they should be distinguished from non-neoplastic reactions associated with implants, such as infection and a reaction to prosthetic wear debris.

Surgical treatment of primary pulmonary sarcomas

OBJECTIVE We sought to identify the long-term prognosis after surgical treatment for primary pulmonary sarcoma. METHODS Twenty-three patients were retrospectively identified as having been treated surgically for primary pulmonary sarcoma between 1981 and 1996. The records of all patients were reviewed, and the histopathology reexamined by a pathologist. RESULTS Fifteen patients were male and eight female; their ages ranged from 20 to 78 (mean 51) years. Tumors measured between 0.9 and 12.0 (mean 5.2) cm across the greatest diameter. The histologic diagnoses were malignant fibrous histiocytoma (8, three grade 1 or 2, two grade 3), synovial sarcoma (4), malignant schwannoma (3), leiomyosarcoma (3), and one case each of angiosarcoma, intimal sarcoma, epitheloid hemangioendothelioma, fibrosarcoma and primitive neuroectodermal tumor. Three patients were found to be unresectable. All three underwent radiation and chemotherapy. Lobectomies or bilobectomies were performed in 13 patients including two sleeve resections, one carinal resection, and one chest wall resection. Four patients underwent radical pneumonectomies. Three patients with invasion of the pulmonary artery, pulmonary veins or atrial wall underwent extended resections with the use of cardiopulmonary bypass. In two, a homograft was used to reconstruct the right ventricular outflow tract. Of the resected patients, six had a positive resection margin, and four had at least one positive lymph node in the specimen. Three patients underwent repeat pulmonary resections for recurrences. Eleven patients received postoperative chemotherapy and eight had radiation therapy. Follow-up was available on 22 patients, and ranged from 2 to 183 (mean 48) months; 14 patients are disease free, six died of disease, one died of surgical complications (operative mortality 5%), and two are alive with disease. Actuarial 3- and 5-year survival of the resected patients was 69%. Size and grade were not found to be correlated with significantly increased survival, but completeness of resection was (P<0.05). CONCLUSIONS Resection of primary pulmonary sarcomas can produce an acceptable survival rate if the resection is complete. Cardiopulmonary bypass can be a useful adjunct when tumors involve a resectable area of the heart or great vessels.

Histological pattern of mandibular invasion by oral squamous cell carcinoma.

Objective: Mandibular invasion by oral squamous cell carcinoma may progress by either an infiltrative or an erosive histological pattern. The infiltrative pattern is marked by nests and cords of tumor cells along an irregular tumor front, and the erosive pattern exhibits a broad, pushing tumor front. The objectives of this study were 1) to define the characteristics associated with each histological pattern of mandibular invasion, 2) to assess the relationship between pattern of invasion and clinical outcome as measured by death with disease and disease presence at last follow‐up, and 3) to determine whether the cell cycle markers cyclin D1 and Ki‐67 are associated with the histological pattern of invasion or are predictive of outcome.

Chondromyxoid fibroma of the skull base: A tumor which may be confused with chordoma and chondrosarcoma: A report of three cases and review of the literature

Three cases of chondromyxoid fibroma arising in the skull base are reported. The tumors arose in females 34, 65, and 66 (median 55) years of age. Two women presented with headaches, and one with nasal obstruction. Radiographic studies revealed that all three lesions were expansile soft tissue masses centered in the clivus, at least 4 cm in greatest diameter. One lesion involved primarily the clivus, the others extended from the clivus into the sphenoid and ethmoid sinuses. Two of the three cases were initially misdiagnosed as chordoma or chondrosarcoma. The initial treatment was curettage of gross disease in all three cases. One patient also received radiation therapy. One patient had local progression of disease, which was treated with surgery and radiation therapy. All patients are clinically free of disease 11 to 26 months following the most recent treatment. Chondromyxoid fibroma can and should be distinguished from chondrosarcoma and chordoma, two tumors which more commonly arise in the skull base and which have the potential to metastasize.

Hyalinizing spindle cell tumor with giant rosettes: a report of three cases with ultrastructural analysis.

We report the light microscopic, ultrastructural appearance and immunohistochemical staining profile of three distinctive soft-tissue tumors recently designated hyalinizing spindle cell tumor with giant rosettes. The tumors occurred in two men, 41 and 54 years old, and one woman, 62 years old. Two tumors arose in the lower extremities and one in the upper arm. Two tumors were resected and measured 3 and 13.2 cm in greatest diameter; a biopsy only was done of the third tumor. Grossly, the tumors had a tan, pink, or white cut surface. The largest tumor exhibited central cystic change. Microscopically, they all displayed similar features and were composed of fibromyxoid regions, with areas of hyalinization in two tumors and focal ossification in one tumor. Scattered throughout each of the tumors were rosette-like structures in which neoplastic cells were arranged around a central collagenous core. Ultrastructurally, the neoplastic cells demonstrated the features of fibroblasts. In all tumors, there was abundant extracellular collagen fibers and in one there were large aggregates of amorphous extracellular external lamina-like material. The center of the rosette-like structures was composed of banded collagen fibers and the cells at the periphery of the rosettes had ultrastructural features similar to the neoplastic spindle cells located elsewhere in the tumor. Immunohistochemically, the tumor cells stained for vimentin. There was focal staining of the widely distributed spindle cells and cells that formed the rosettes for Leu-7, S-100 protein, and CD34. In one tumor, there was faint diffuse staining of the spindle cells for neuron-specific enolase. One tumor (with the amorphous extracellular material) stained for type IV collagen. There was no staining for desmin, muscle actin, smooth muscle actin, keratin, or epithelial membrane antigen. These results demonstrate that hyalinizing spindle cell tumor with giant rosettes is composed of fibroblasts. We did not demonstrate any ultrastructural or immunohistochemical differences between the spindle cells that comprised the majority of the mass and those that surrounded the rosette-like structures. There was no ultrastructural evidence of neural differentiation to explain the focal S-100 protein and Leu-7 staining of the tumor cells.

A pancreatic endocrine tumor arising within a serous cystadenoma of the pancreas.

We report a pancreatic endocrine tumor arising within an otherwise benign pancreatic serous cystadenoma in a 47-year-old woman with a history of lupus treated by steroids. She presented 10 years before resection with epigastric pain and intermittent jaundice. Histologic and immunohistochemical studies showed that the solid endocrine component was composed of small, uniform cells with stippled nuclei, which were chromogranin A positive. The surrounding cystic component was lined by periodic acid Schiffs-positive, diastase-digestible cells containing glycogen. To the best of our knowledge, this is the first case of a serous cystadenoma of the pancreas that contains a well defined pancreatic endocrine tumor reported in the English literature.

Hemorrhagic epithelioid and spindle cell hemangioma: a newly recognized, unique vascular tumor of bone.

Epithelioid vascular tumors of bone are uncommon and include epithelioid hemangioma, epithelioid hemangioendothelioma, and epithelioid angiosarcoma. It is important to distinguish among them because they have significantly different biologic potential and require different forms of therapy. In the current study the authors describe six cases of a distinct benign epithelioid and spindle cell vascular tumor of bone that, because of their unusual morphology, were confused with aggressive vascular neoplasms.

Fine-needle aspiration of dedifferentiated chondrosarcoma of the larynx.

We present a case of dedifferentiated chondrosarcoma of the larynx in which the dedifferentiated component was initially diagnosed by fine‐needle aspiration (FNA). The patient was a 74‐yr‐old man who presented with difficulty breathing and an anterior neck mass. A CT scan demonstrated a 4.5‐cm cartilaginous lesion involving the left thyroid cartilage, with an anterior soft‐tissue component. Nine years prior, the patient had an incomplete resection of a low‐grade chondrosarcoma at the same site. FNA was performed on the current lesion, demonstrating a high‐grade spindle‐cell sarcoma with a storiform pattern. The cytomorphology together with immunocytochemistry and electron microscopy were diagnostic of malignant fibrous histiocytoma (MFH), and synthesis of the clinical, radiographic, and cytomorphologic features resulted in a diagnosis of dedifferentiated chondrosarcoma. The cytologic diagnosis was histologically confirmed by laryngectomy. Although rare, dedifferentiated chondrosarcoma should be included in the differential diagnosis of high‐grade sarcomas of bone and cartilage assessed by FNA. Diagn. Cytopathol. 2000;22:288–292.