Showing papers by "Saul Suster published in 1991"

Thymic carcinoma. A clinicopathologic study of 60 cases.

Abstract: The clinicopathologic features of 60 patients with thymic carcinoma were studied. Patients ranged in age from 10 to 76 years (mean, 46), of whom 24 were females and 36 were males. Overall survival at 1, 3, and 5 years was 56.6%, 40%, and 33.3%, respectively. The following morphologic features were correlated with survival: type of tumor margins; presence or absence of a lobular growth pattern; nuclear atypia; necrosis; mitotic activity; and histologic tumor type and grade. Eighty eight percent of patients with poorly circumscribed/infiltrating neoplasms died of their tumors as compared with 16.6% of patients with well-circumscribed neoplasms (P less than 0.0000). Of patients whose tumors had mitotic counts exceeding 10/10 high-power fields (HPF), 84.3% died, as compared with 21.4% of patients with lower mitotic counts (P less than 0.0000). Of patients whose tumors showed lack of lobular growth pattern, 91.6% died, as compared with 29% of those whose tumors had a lobular growth pattern (P less than 0.0000). Finally, 84.6% of patients whose tumors displayed a high-grade histology (lymphoepithelioma-like carcinoma, small cell/neuroendocrine carcinoma, clear cell carcinoma, sarcomatid carcinoma, and anaplastic/undifferentiated carcinoma) died of tumor, as compared with 0% of patients whose tumors were of low-grade histology (well-differentiated squamous carcinoma, mucoepidermoid carcinoma, and basaloid carcinoma) (P less than 0.0000). Evaluation of the various treatment modalities used to treat these patients did not yield any statistically significant correlations with survival. Two clinically distinct groups of patients were identified: one after a relatively favorable clinical course with long survival, and one after a rapidly fatal outcome. The morphologic features of the tumors in these patients correlated well with their clinical behavior; histologic type (and the grade to which it was assigned) constituted the most reliable and important predictor of prognosis.

Multilocular Thymic Cyst: An Acquired Reactive Process Study of 18 Cases

Abstract: The clinical and pathologic features in 18 cases of multilocular thymic cyst (MTC) of the anterior mediastinum unassociated with Hodgkin's disease or seminoma were studied. The majority of cases were asymptomatic and discovered incidentally on routine chest x-ray. Several patients presented with acute symptoms of chest pain or discomfort, sometimes associated with dyspnea. Two cases had an incidental thymoma, and two had an incidental thymic carcinoma. The main histologic features of MTC included the following: multiple cystic cavities partially lined by squamous, columnar, or cuboidal epithelium (some having features of Hassall's corpuscles); scattered nests and islands of non-neoplastic thymic tissue within the cyst walls, often continuous with the cyst lining; severe acute and chronic inflammation accompanied by fibrovascular proliferation, necrosis, hemorrhage, and cholesterol granuloma formation; and reactive lymphoid hyperplasia with prominent germinal centers. These features suggest that MTC most likely results from the cystic transformation of medullary duct epithelium-derived structures (including Hassall's corpuscles) induced by an acquired inflammatory process. The changes are similar to those sometimes seen in association with thymic Hodgkin's disease and thymic seminoma, which are also probably due to the inflammation that accompanies these tumors rather than to the tumors themselves. We believe that MTC is pathogenetically analogous to a variety of cystic conditions of the head and neck region, for which the common denominator seems to be the induction of cystic transformation in ductular epithelial formations of branchial pouch or related derivation by an acquired inflammatory process.

Induction of different morphologic features of malignant melanoma and pigmented lesions after transformation of murine melanocytes with bFGF-cDNA and H-ras, myc, neu, and E1a oncogenes.

Abstract: Malignant melanomas show a remarkable degree of heterogeneity because of different morphologic features, biologic behavior, and prognosis. In this communication, the authors attempted to correlate morphologic heterogeneity of melanomas with transformation by different activated oncogenes; they studied the histologic features of melanocytic lesions induced by murine melanocytes transformed by basic fibroblast growth factor (b-FGF-cDNA) or H-ras, neu, myc, and E1a oncogenes, and the lesions were compared with those observed in human pathology. Tumors formed after grafting onto syngenic mice or subcutaneous injections in nude mice were studied. In syngenic mice, benign melanocytic lesions reminiscent of intradermal nevus were observed with melanocytes transformed with b-FGF-cDNA, and myc and E1a oncogenes. Benign lesions were also formed by neu-transformed melanocytes when they were grafted concomitantly with keratinocytes, whereas malignant tumors were formed by the same cells when grafted alone or together with fibroblasts. In contrast, H-ras melanocytes always formed malignant tumors. In nude mice, b-FGF-transformed melanocytes induced benign lesions, whereas transformed melanocytes by the other oncogenes formed malignant tumors with distinctive and homogeneous morphologic features that depended on the transforming oncogene. Melanomas with either epithelioid cell, spindle cell, small round cell, and anaplastic cell growth patterns could be distinguished after transformation with H-ras, neu, E1a, and myc oncogenes, respectively. These various histologic types are analogous to those that may be observed in human melanomas, even within the same tumor. These studies suggest a possible molecular mechanism for tumor heterogeneity in which distinct oncogenes or oncogenelike activities can be activated in different tumors or discrete parts of the same tumor.

Myoepithelial differentiation in basal cell carcinoma.

Abstract: Five cases of basal cell carcinomas (BCC) of the skin are described showing morphologic and immunohistochemical features of myoepithelial differentiation. Histologically, they were characterized by a dermal proliferation of tumor cells connected with the epidermis by areas showing the features of conventional BCC, with the deeper portions of the lesion showing a population of oval to spindle cells with eccentric nuclei and homogeneous, ground-glass, or hyaline eosinophilic cytoplasm characteristic of the so-called hyaline cell of myoepithelial tumors of salivary glands. Additionally, scattered cells showing a signet ring configuration were present, and in two cases, focal areas displaying chondromyxoid elements were also seen that appeared to merge imperceptibly with the surrounding spindle cell population. By immunohistochemistry, the tumor cells in the spindle cell component showed strong, diffuse positivity for CAM 5.2 and muscle specific actin, and variable expression of keratin AE1/AE3, vimentin, glial fibrillary acidic protein, and S-100 protein, these findings being consistent with the immunostaining pattern of myoepithelial cells and their neoplasms. A brief review of the literature on the topic is presented, along with a discussion of the possible pathogenesis of this process.

Syringomatous squamous tumors of the breast

Abstract: Four cases are reported of syringomatous squamous tumors of the breast occurring in women aged 37 to 70 years. The lesions were characterized histologically by relatively well-circumscribed tumor-like nodules composed of a proliferation of teardrop or comma-shaped islands of squamous epithelium. The squamous epithelial islands contained central lumens lined by eosinophilic cuticles and were surrounded by a densely cellular fibrous matrix, thus closely resembling the growth pattern of dermal eccrine syringomas. The lesions appeared to arise de novo from breast parenchyma without evidence of transitions with the surrounding normal or hyperplastic mammary epithelium and were not associated with the overlying skin or nipple epidermis. In all cases, the surrounding breast tissue showed fibrocystic and benign proliferative changes, and in one case, the lesion was found in the vicinity of a large cyst surrounded by microcalcifications. All patients were treated by local surgical excision and have shown no evidence of recurrence over a follow-up period of 1 to 6 years. The histologic differential diagnosis and the possible pathogenesis of these lesions are discussed.

Primary thymic epithelial neoplasms in children.

Abstract: Primary epithelial neoplasms of the anterior mediastinum in children are very rare. We have studied 10 cases of thymic epithelial neoplasms in children aged 16 years or less and correlated their histologic features with the clinical outcome. The patients' ages ranged from one to 16 years (mean: 10.2); with a male:female ratio of 1.5:1. Nine patients had symptoms attributable to their tumors; one was asymptomatic. Four patients presented in clinical stage I, one in stage IIb, and five in stage IVb. Histologically, the tumors comprised a heterogenous group displaying a range of morphologic appearances: one tumor had the classic features of lymphocyte-rich thymoma of the adult; four were of the lymphocyte-rich type with associated unusual stromal features; two were spindle cell thymomas with cytologic and architectural atypia; and three displayed obvious cytologic features of malignancy (i.e., thymic carcinoma); two in the last group showed features of small cell carcinoma, and the other was an undifferentiated/anaplastic carcinoma. The epithelial nature of the tumors was supported in six cases by positive staining of the tumor cells with keratin antibodies and in two cases by electron microscopic demonstration of desmosomes and intracytoplasmic bundles of tonofilaments within the tumor cells. The prognosis for these patients correlated well with the degree of atypicality exhibited by the epithelial components; it was very poor in patients with small cell and undifferentiated/anaplastic carcinoma (8 months average survival), better for those with atypical spindle cell thymomas (multiple recurrences and metastases but no fatalities over a 15- to 72-month period), and best in those with lymphocyte-rich thymomas without cytologic atypia (no recurrences or metastases over an 8-month to 3-year follow-up).