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S F Cramer

Publications and source records attributed to S F Cramer.

At least 55 records · Page 3Linked to original sources
PubMed1989

Signet-ring squamous cell carcinoma.

Among carcinomas, signet-ring morphologic characteristics have been regarded as pathognomonic of adenocarcinoma. This report presents the case of a poorly differentiated cutaneous squamous cell carcinoma with a monodispersed, invasive signet-ring component. Kreyberg stains had negative results for mucin. Immunohistochemical analysis demonstrated that concentric rings in the signet-ring cells were composed of keratin. To the best of the authors' knowledge, this is the first report of signet-ring squamous cell carcinoma. Another feature that bears emphasis is that this squamous cell carcinoma led to the death of the patient, even though it originated in a field of actinic keratosis.

Adenocarcinoma, Mucinous↗
PubMed1989

Impact of diagnostic immunohistochemistry on the recognition and management of two cases of thyroid cancer with protracted courses.

This report presents two cancer cases with protracted courses in which diagnostic immunohistochemistry for thyroglobulin and/or calcitonin was performed several years after the original light microscopic interpretation. In both cases, diagnostic immunohistochemistry suggested significant changes in tumor classification. In light of current controversies and interpretive problems in this area, confirmatory tests for serum calcitonin and serum thyroglobulin and scans for iodine 131 uptake were performed. These confirmed the immunohistochemical evidence, and led to major changes in patient management. Several similar cases were found in the literature. In cancer cases with a protracted course, but with atypical or discordant clinical and/or pathologic features, diagnostic immunohistochemistry for thyroid markers may merit consideration because of the potential for meaningful changes in clinical management.

Adenocarcinoma↗
PubMed1988

Benign glandular inclusions in parotid nerve.

Benign salivary ductular and acinar structures were demonstrated within an enlarged, disorderly intraparotid nerve in association with a mucoepidermoid carcinoma that did not, itself, manifest perineural invasion. Salivary gland can thus be added to the growing list of tissues in which "perineural invasion" by noncancerous epithelium has been observed. The proliferative features of the neural tissue in this case support the notion that neural elements may play an active role in the establishment of intimate neural-epithelial relationships. The mechanism for this phenomenon in the present case is postulated to be proliferation and ingrowth of the nerve tissue, possibly mediated by nerve growth factor or some related substance.

Aged↗
PubMed1988

The melanocytic differentiation pathway in congenital melanocytic nevi: theoretical considerations.

It is suggested that the melanocytic series is characterized by a differentiation pathway (MDP) that has four discrete stages during normal development and in postnatal tissue maintenance--nerve sheath precursor (nsp), dermal migratory, junctional migratory, and dendritic--and that congenital melanocytic nevi (CMN) derive from cells in the nsp stage of the MDP. This concept accounts satisfactorily for morphologic variations and clinicopathologic correlations in CMN. It also permits a unified explication of both similarities and differences between congenital and acquired melanocytic nevi (AMN), which are thought to arise by transformation of nsp cells in the MDP during postnatal tissue maintenance. This perspective suggests that answers to many basic questions about CMN may require meticulous study of the interrelations of CMN with peripheral nerve elements. Such research may be necessary to resolve current controversies about optimal criteria for distinguishing small CMN from AMN, thereby permitting an accurate assessment of the risk of malignant melanoma in association with small CMN.

Cell Differentiation↗
PubMed1987

Accuracy of frozen section diagnosis of the salivary gland.

Three hundred and one salivary gland lesions (162 benign, 72 malignant, and 67 benign non-neoplastic) of 677 cases were evaluated by use of intraoperative frozen sections by 66 pathologists. In seven patients, the diagnosis was deferred for permanent sections. In four cases (1.3%), the diagnosis at permanent section changed from one category of benign tumor to another, and in five cases (1.7%), from one category of malignant tumor to another. In four tumors, a frozen section diagnosis of benign was changed to malignant on permanent sectioning; all four involved acinic cell carcinomas. Only two tumors were incorrectly diagnosed as malignant. We conclude that diagnoses of most salivary gland lesions based on frozen section examination are reliable and accurate. However, the literature does indicate that caution should be exercised when malignant tumors are dealt with.

Diagnosis, Differential↗
PubMed1987

Evaluation of the reproducibility of the World Health Organization classification of common ovarian cancers. With emphasis on methodology.

Seven pathologists independently classified 50 slides of ovarian tumors using category I of the World Health Organization classification (WHO I), each case being seen twice under different random code numbers. Intraobserver reproducibility and interobserver reproducibility, based on consistent interpretations, were both suboptimal. However, scrutiny suggested that no pathologist was a source of excessive variability, nor was suboptimal interobserver reproducibility simply due to intraobserver variability. Neither could excessive variability be attributed to skewing of results by a subgroup of unclassifiable cases. However, clearcut sources of variability were identified among the categories of WHO I, namely, mixed epithelial, unclassified epithelial, and undifferentiated carcinoma. There was also considerable variability in distinguishing serous and endometrioid neoplasms, and in identifying tumors of low malignant potential. These findings should not be misconstrued as implying that pathologists in routine practice cannot diagnose common ovarian cancers reproducibly for patient care purposes. Availability of clinical and macroscopic data, extensive sampling, histochemistry, and consultation combine, in an uncontrolled and highly individualistic fashion, to render routine service work very different from this highly controlled formal exercise. Furthermore, at the current state of the therapeutic art, many of the taxonomic problems identified in this study may have little clinical significance. Nonetheless, this study has strengthened the evidence that there may be important problems in classifying common ovarian cancers reproducibly using WHO I, and that WHO I may require greater clarity to enhance reproducibility. Current emphasis on quality assurance dictates reconsideration of the literature on reproducibility of histopathologic taxonomy, which has tended to inculpate pathologists as sources of variability. Virtually all of this literature is subject to some degree of skepticism due to deficiencies in methodology. Consideration of the question of how to measure reproducibility in anatomic pathology leads us to suggest that the community of pathologists should address the need to decrease ambiguity in classification systems as an important step toward optimizing reproducibility.

Female↗
PubMed1986

Squamous differentiation in colorectal adenomas. Literature review, histogenesis, and clinical significance.

Patterns of stratified squamous epithelium have been recognized recently in colorectal adenomas. Light microscopic and keratin immunohistochemical analysis of four cases in the present report suggested origin from large intestinal reserve cells, with impaired and disorderly maturation in the squamous foci. One case had an invasive adenocarcinoma separately in the same polyp, bringing the reported incidence of malignant transformation in these adenomas to seven of 48 (15 percent). Evidence is presented to support the notion that squamous differentiation may be an inherently neoplastic phenomenon in colorectal adenomas, which may be added to the list of markers for colorectal polyps at higher risk for malignant transformation.

Adenocarcinoma↗
PubMed1985

Growth potential of human uterine leiomyomas: some in vitro observations and their implications.

Tissue culture techniques commonly applied to the study of human vascular smooth muscle were used to evaluate in vitro survival and proliferation of normal and neoplastic human myometrial cells. Despite their growth advantage in vivo, leiomyoma cells displayed a growth disadvantage in vitro compared with normal myometrium from the same patient. Hormonal supplementation with alpha-estradiol, progesterone, and insulin-stimulated myometrial proliferation, whereas beta-estradiol appeared ineffective at the doses tested. Hormonal supplementation also stimulated leiomyoma proliferation in vitro, but there appeared to be heterogeneity in hormonal responsiveness. Heterogeneity in the host hormonal milieu and in the ability of uterine leiomyomas to respond to various hormones may be important factors contributing to the wide variation in growth potential observed in leiomyomas.

Adult↗
PubMed1984

The histogenesis of acquired melanocytic nevi. Based on a new concept of melanocytic differentiation.

A new concept of melanocytic differentiation during normal development is presented, suggesting that 1) normally developing melanocytes and Wagner-Meissner bodies are both derived from primitive, pluripotential precursors in the perineural region of fetal cutaneous nerves; and 2) melanocytes, like keratinocytes and many other cell series, have a differentiation pathway with discrete stages. The proposed stages of the melanocytic differentiation pathway are: the nerve-sheath precursor stage, the dermal migratory stage, the junctional migratory stage, and the dendritic stage. This theory is consistent with current knowledge of human embryology, present understanding of the biology of cells derived from the neural crest, and modern concepts of stem cells and differentiation. Based on this concept, it is proposed that the commonly encountered types of acquired melanocytic nevi derive from pluripotential cells in the nerve-sheath precursor stage of the melanocytic differentiation pathway. As the progeny of these precursors attempt to mature along the pathway, they may produce various patterns that may be interpreted as caricatures of the stages in the pathway. In particular, maturation of most elements to the dendritic stage may produce the pattern of lentigo simplex; predominance of maturation to the junctional migratory stage may produce the pattern of junctional nevi; predominance of maturation to the dermal migratory stage may produce the pattern of intradermal nevi; and failure of progeny to mature along the melanocytic differentiation pathway may produce the pattern of neuroid nevi. This histogenetic model accounts satisfactorily for morphologic variations and clinicopathologic correlations in acquired melanocytic nevi.

Cell Differentiation↗
PubMed1984

The neoplastic development of malignant melanoma. A biological rationale.

It is suggested that melanocytes may be characterized by a differentiation pathway with four distinct stages during normal tissue maintenance: the nerve-sheath precursor stage, the dermal migratory stage, the junctional migratory stage, and the dendritic stage. Carcinogenic action on cells in these four stages may produce four classes of lesions: neurotropic melanoma, invasive malignant melanoma, epidermal melanocytic precursors of invasive malignant melanoma, and isolated atypical epidermal melanocytes. Morphologic variations within a class are interpretable as reflecting varying degrees of aberration from the behavior of normal cells in the corresponding stage. This theory accounts for morphologic variations and salient clinicopathologic correlations during the neoplastic development of malignant melanoma. It is consistent with fundamental principles of carcinogenesis, modern ideas about stem cells and differentiation, and current understanding of the pathogenesis of metastasis. It may be of some value in resolving present controversies and may contribute to the development of improved methods of diagnosis and management of malignant melanoma. Further study is necessary before these concepts may be prudently applied in clinical practice.

Cell Differentiation↗