Case Report Dermatology 1992; 185:291-295
Department of Dermatology. Catholic University of Louvain, Belgium
Key Words Dermatofibrosarcoma protuberans Myofibroblast Labyrinthic nucleus Ultrastructure
Dermatofibrosarcoma protuberans: Ultrastructural Investigation
Abstract The ultrastructural aspects of nucleus and cytoplasm of tumor cells and the inter stitial material of dermatofibrosarcoma protuberans are described in detail, especially the very peculiar labyrinthic nucleus. Opinions about its development are reviewed; some, such as melanocytic, neural, histiocytic and smooth muscle proliferation, might be discarded. The myofibroblast appears as the most prob able stem cell.
Introduction Surprisingly enough, the cytogcncsis of dermatofibro sarcoma protuberans (DFP) remains elusive despite the numerous publications dealing with histology, culture char acteristics and electron microscopic features; various hypo theses have been brought up on account of these findings. Circumstances allowed us to investigate 2 cases in great detail at the ultrastructural level and to comment on the lit erature.
Case Report Tiny hard nodules had developed very slowly for 50 years within the abdominal skin of a 70-year-old man. but more slowly during the last 2 years. Biopsy and surgical specimens disclosed intense ‘fibro blastic" proliferation, thick entangled fascicles of cells and storiform pattern, plenty of small vessels, heavy deposits of collagen and nuclei somewhat larger and less regular than usual. A 65-year-old female presented her first lesions 30 years ago but never accepted surgery; the tumor had invaded the whole scapular area and become cumbersome. Under the microscope, the material appears less homogenous: in infiltrated areas, the same pattern pre vails: in nodules, cells multiply more intensively and nuclei appear dark
er and irregular; elsewhere, a thorough remodelling is characterized by a low content of collagen fibers, myxoid pattern, fusiform or globu lar or stellate cells with large nucleus. There is extension within the underlying muscles: there is an impressive network of small vessels. Two other cases, with shorter evolution, provided similar but less impressive pictures, even under the electron microscope, and so far were not considered for description.
Material and Methods Pieces of tissue, duly trimmed, were fixed in glutaraldehydc (3%, pH 7.4. cacodylate buffer) and osmium tetroxide (1%. pH 7.4. phos phate buffer), embedded in Epon-812. cut on a Porter-Blum PT2 ultramicrotomc. contrasted with uranyl acetate and lead citrate and investigated with a Philips EM300 electron microscope.
Results Nucleus Some 25% of nuclei are those of active fibroblasts, elon gated and even ribbon-like, with smooth outlines and shal low depressions. Most nuclei display extreme convolution and even segmentation. There are large and deep infold-
Prof. A. Bourlond Department of Dermatology. Faculty of Medicine Catholic University of Louvain 52. avenue Li. Mourner Tour Vesalc B-1200 Brussels (Belgium)
© 1992 Karger AG. Basel 1018-8665/92/1854-0291 S 2.75/0
Downloaded by: Univ. of California Santa Barbara 128.111.121.42 - 3/6/2018 9:48:24 AM
A . Bourlond C. Marcoux
Fig. 1. Typical labyrinthic nucleus showing nuclear bridges (arrow) and pseudoinclusions (asterisk), x I8.(X)0.
Fig. 2. Intricate nuclear bridges (arrow) and pseudoinclusions (asterisk) are highly characteristic of the hyperconvoluted and hypersegmented nucleus, x 37.000.
292
Bourlond/Marcoux
ments, channels and bridges as well as cytoplasmic pscu doinclusions and pseudo-pseudoinclusions lead to the con struction of hyperconvoluted, hypersegmented. labyrinthic nuclei (fig. 2). Chromatin, of low density, condenses slightly beneath the nuclear membrane. Mitoses are occasional; nuclear pores remain scarce; the perinuclear cisterna is absolutely clear but of varying width. The nucleolus is apparently nor mal or quite large and muriform. In somes instances, it is localized at the level of symmetrical infolding and adheres to the opposite inner side of the nuclear membrane (fig. 3). Nuclear or virus-like inclusions, as described by Hcntzcr and Kobayasi [l], develop occasionally.
Dermatofibrosarcoma protuberans
Downloaded by: Univ. of California Santa Barbara 128.111.121.42 - 3/6/2018 9:48:24 AM
ings of the nuclear membrane with constitution of the socalled cytoplasmic pscudoinclusions (fig. I). There are many outward projections of the nuclear membrane with or without ampullar dilatation; narrow ones deserve the deno mination of nuclear channels. Quite often adjacent mem branes come into close contact and constitute nuclear bridges; there is a dark central line (apposition if not fusion of the nuclear limiting zone), two adjacent thin lines (nuclear membrane), perinuclear cisterna and its cytoplas mic membrane. Sometimes adjacent projections isolate cytoplasmic areas, which are considered by contrast as pseudo-pseu doinclusions. Multiplication of nuclear projections, seg
Fig. 3. a Large nucleolus seals the nuclear space between opposite infold ing of the plasmalemma. x 19.000. b Some tumor cells contain a well developed cilium associated with the Golgi apparatus, x 24.000.
Cytoplasm Most of the cells arc elongated, they develop in ribbon like slender processes. Generally, cells and extensions are established in somewhat laminated and parallel bundles. Plasmalemma appears smooth and wavy and supports only pinocytic vesicles in a low number. Very discrete condensation of extracellular amorphous or finely granular material is observed here and there along the membrane. Never impressive or regular, it can hardly be considered as a primitive basement membrane (fig. 4). Close contacts of adjacent cells in the way of tight junctions are exceptional. Cytoplasm is scanty and densities slightly around the nucleus. It shows few profiles of rough surfaced endoplasmic reticulum. Golgi apparatus is never developed; mitochondrias arc few but dilated. Dense bodies remain inconspicuous. Vacuoles and lipid inclusions exist only in some areas. Quite often in the first case, but rarely in the sec ond case, there are centrioles and even cilia at various stages of development (fig.3). Filaments are few, dispersed or loosely tight in tiny bundles, without densification and with out evident adherence plaques to the cell membrane - a fea ture quite distinct from that of smooth muscle cells.
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Fig. 4. a Capillary showing normal-looking endothelial (E) and pcrithelial (P) cells; outside of it. another cell might be considered ‘transitional’, x 11.2(H). b Tumor cells with a labyrinthic nucleus pre sent sometimes dark inclusions and 'basement membrane-like' mate rial (arrow), x 16.500.
Discussion Labyrinthic nuclei have already been described in detail by Aubôck [2]; they appear quite common in DFP [2. 3] and giant cell fibroblastoma [4]. However, they have been observed also in other aggressive fibroblastic proliferations [2, 3] and low-grade malignant tumors with low mitotic index [4], The nuclear appendages, the so-called nucleotesimals, might represent a peculiar type of amitosis [5]. The present observation does not provide any clues in favor of the melanocytic origin (or participation); even in desmoplastic melanotic lesions, melanosomes ought to be seen even in low number. The finding of melanocytes in one instance [6] remains puzzling. Labyrinthic nuclei, almost nonexisting basement mem brane, poorly structured lamellar extensions of the cyto plasm. absence of pseudocorpuscular bodies, extreme dis persion if not absence of nerve fibers, exceptionally long spacing collagen fibrils represent cumulative evidence against the neural theory; Fisher and Vuzevski [7], as well as Zina and Bundino [8]. reach similar conclusions. On the other hand, Hashimoto et al. [6] note a great number of long spacing collagen fibrils and Alguacil-Gar d a et al. [9] hold that tumor cells have marked ultrastruc tural similarities with the perineural cells. Such discrepancies result most probably from the level and quality of differentiation of tissues and the poor relia bility of microscopic samples. Histiocytic proliferations may be doubted; in such instances, cells appear more globular and loaded with a
294
B outiond/M arcoux
larger amount of lipid and phagocytic inclusions and pos sibly Langerhans granules. Alguacil-Garcia et al. [9] dis card also this hypothesis; on the contrary, Ozzcllo and Hamels [10] and Yoshida ct al. [II] present impressive arguments from their observations of cultured tumoral tis sues but technical procedures might have modified the met abolic behavior of cells. A pure fibromatous tumor does not fit easily, even if Zina and Bundino [8] and Escalona-Zapata ct al. [12] accept the fibroblastic nature of the tumor cells. The colla gen content is too low, even for myxoid stroma, and the cytoplasm does not appear really active as commonly observed in young fibroblasts. The pilo-angioleiomyoma origin appeals at first but proves definitively unacceptable: there arc no characteristic smooth muscle cells, myofibril lar differentiation, axial localization of organelles, base ment membrane or satellite nerve fibers. It might be hypothesized that perithelial cells, heavily irritated, might participate as transitional elements; it seems more sensible to consider them as comparse pcrithelial cells, parallel to the circumference of the vessels, provided with slender and clear cytoplasm, loaded with few organelles and con voluted nucleus. It must be stressed that tumor cells never impinge upon the vessel wall and do not blend with the perithelial apparatus; on the contrary, a thick layer of amorphous or microfibrillar material separates them clearly. The myofibroblast has been proposed as a reactive fibroblast [13-16]; its main characteristics arc: elongated nucleus with infoldings, ribbon-like cytoplasm with a lot of organelles and bundles of (myo)-filaments, pinocytic vesi cles, tight junctions and some basement-like material. Even if considered as a hypothetical cell, it nevertheless represents a highly convenient tool to look at fibroblastic hyperplasias and tumors [17-19], A reappraisal of the functions and histochemical pro perties of such a cell in scleroderma has been recently pre sented by Sappino et al. [21]. Even if it has been described with a larger component of organelles and filaments, the myofibroblast fits as the stem cell of DFP. if we accept that it loses part of its character istics while engaged in intense or wild proliferation. At least, striking similarities make this hypothesis the most appealing one. Schmoeckel ct al. [20] propounded the fibroblastic nature at large of dermatofibrosarcoma protuberans; nevertheless they added, interestingly enough, that ‘the presence of basal membranes and intracytoplasmic filaments in case 6 suggested that myofibroblasts were the origin of this tumor’. Further enzymatic and immunological studies are needed to ascertain this theory.
Dermatofibrosarcoma protuberans
Downloaded by: Univ. of California Santa Barbara 128.111.121.42 - 3/6/2018 9:48:24 AM
Intercellular Space It is characterized by amorphous material, tangles of collagen fibrils and fibers, exceptionally long spacing colla gen fibers or Luse bodies. Unmyelinated fibers, quite rare and devoid of perineural sheath, do not come into contact with the tumor cells. Melanocytes, mast cells, Langerhans cells are definitively absent; inflammatory cells and histio cytes arc exceedingly rare. Especially in the second case, capillaries proliferate. Their lumen stays wide open but is often filled with erythrocytes. Turgescent endothelial cells contain numerous organelles such as Wcibcl-Paladc cigar bodies and filaments. Prominent pcrithelial cells contain a high-density cyto plasm and a large dark nucleus. Pcripherically to these cells, there are others that might be considered transitional because they show elongated and wavy outline, moderate load of organelles, indented nucleus, segmental basement membrane (fig.4). Their significance is discussed below.
References 9 Alguacil-Garda A. Unni K. Goellncr JR: Histogenesis of dermatofibrosarcoma protube rans. An ultrastructural study. Am J Clin Pathol 1978;69:427-434. 10 Ozzello L. Hamels J: The histiocytic nature of dermatofibrosarcoma protuberans. Tissue cul ture and electron microscopy study. Am J Clin Pathol 1976:65:136-148. 11 Yoshida H. Malsui K. Hashimoto K. Yumoto T. Mihara M: Dermatofibrosarcoma protube rans and its tissue culture study. Acta Pathol Jpn 1982:32:83-91. 12 Escalona-Zapata J. Fernandez EA. Escuin FL: The fibroblastic nature of dermatofibrosar coma protuberans. A tissue culture and ultrastructural study. Virchows Arch 1981:391: 165-175. 13 Gabbiani G. Ryan GB. Majno G: Presence of modified fibroblasts in granulation tissue and their possible role in wound contraction. Experientia 1971:27:549-550. 14 Gabbiani G. Majno G: Dupuytren’s contrac ture: Fibroblast contraction? An ultrastruc tural study. Am J Pathol 1972:66:131-146. 15 Roland J : Fibroblaste et myofibroblaste dans le processus granulomateux. Ann Allât Pathol (Paris) 1976:21:37-44.
16 Ryan GB. Cliff WJ. Gabbiani G. Irle C, Monlandon D. Statkov PR. Majno G: Myofibro blasts in human granulation tissue. Hum Pathol 1974:5:55-67. 17 Bhawan J. Bacchetta C. Joris I. Majno G: A myofibroblastic tumor. Infantile digital fibroma (recurrent digital fibrous tumor of childhood). Am J Pathol 1979:94:19-36. 18 Kalcnkamp D. Stiller D: Cellular composition of the so-called dermatofibroma (histiocytoma cutis). Virchows Arch 1975;367:325-336. 19 Wirman JA: Nodular fasciitis, a lesion of myo fibroblasts. An ultrastructural study. Cancer 1976.38:2378-2389. 20 Schmoeckcl C. Albini A. KriegT. Stets R: The fibroblastic nature of dermatofibrosarcoma protuberans: Morphological investigations in vivo and in vitro. Arch Dermatol Res 1985; 278:138-147. 21 Sappino AP. Masouye I. Saurat JH. Gabbiani G: Smooth muscle differentiation in scler oderma fibroblastic cells. Am J Pathol 1990: 137:585-591.
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1 1ionizer B. KobayasiT: Nuclear bodies in cells of normal human skin. Acla Derm Venercol 1976:56:429-434. 2 Auböck L: Zur Ultrastruktur fibröser und histiocytärer Hauttumoren (Dermatofibrom. Dermatofibrosarcoma protuberans. Fibroxanthom und Histiocytom). Virchows Arch 1975;368:253-274. 3 Auböck L: 'Labyrinthkerne' bei einem Der matofibrosarcoma protuberans und einem Fibroxanlhom. F.xp Pathol 1976;12:1-18. 4 Shmooklcr li. Enzingcr F. Weiss S: Giant cell Hbroblastoma. Cancer 1989;64:2154-2161. 5 Elias II. Fong BB: Nuclear fragmentation in colon carcinoma cells. Hum Pathol 1978:9: 679-684. 6 Hashimoto K. Brownstein MH. Jakobiec FA: Dermatofibrosarcoma protuberans. A tumor with perineural and endoneural cell features. Arch Dermatol 1974:110:874-885. 7 Fisher ER. Vuzcvski VD: Cylogenesis of schwannoma (neurilemoma), neurofibroma, dermatofibroma, and dermatofibrosarcoma as revealed by electron microscopy. Am J Clin Pathol 1968:49:141-154. 8 Zina AM. Bundino S: Dermatofibrosarcoma protuberans. An ultraslructural study of five cases. J Cutan Pathol 1979:6:265-271.
Department of Dermatology. Catholic University of Louvain, Belgium
Key Words Dermatofibrosarcoma protuberans Myofibroblast Labyrinthic nucleus Ultrastructure
Dermatofibrosarcoma protuberans: Ultrastructural Investigation
Abstract The ultrastructural aspects of nucleus and cytoplasm of tumor cells and the inter stitial material of dermatofibrosarcoma protuberans are described in detail, especially the very peculiar labyrinthic nucleus. Opinions about its development are reviewed; some, such as melanocytic, neural, histiocytic and smooth muscle proliferation, might be discarded. The myofibroblast appears as the most prob able stem cell.
Introduction Surprisingly enough, the cytogcncsis of dermatofibro sarcoma protuberans (DFP) remains elusive despite the numerous publications dealing with histology, culture char acteristics and electron microscopic features; various hypo theses have been brought up on account of these findings. Circumstances allowed us to investigate 2 cases in great detail at the ultrastructural level and to comment on the lit erature.
Case Report Tiny hard nodules had developed very slowly for 50 years within the abdominal skin of a 70-year-old man. but more slowly during the last 2 years. Biopsy and surgical specimens disclosed intense ‘fibro blastic" proliferation, thick entangled fascicles of cells and storiform pattern, plenty of small vessels, heavy deposits of collagen and nuclei somewhat larger and less regular than usual. A 65-year-old female presented her first lesions 30 years ago but never accepted surgery; the tumor had invaded the whole scapular area and become cumbersome. Under the microscope, the material appears less homogenous: in infiltrated areas, the same pattern pre vails: in nodules, cells multiply more intensively and nuclei appear dark
er and irregular; elsewhere, a thorough remodelling is characterized by a low content of collagen fibers, myxoid pattern, fusiform or globu lar or stellate cells with large nucleus. There is extension within the underlying muscles: there is an impressive network of small vessels. Two other cases, with shorter evolution, provided similar but less impressive pictures, even under the electron microscope, and so far were not considered for description.
Material and Methods Pieces of tissue, duly trimmed, were fixed in glutaraldehydc (3%, pH 7.4. cacodylate buffer) and osmium tetroxide (1%. pH 7.4. phos phate buffer), embedded in Epon-812. cut on a Porter-Blum PT2 ultramicrotomc. contrasted with uranyl acetate and lead citrate and investigated with a Philips EM300 electron microscope.
Results Nucleus Some 25% of nuclei are those of active fibroblasts, elon gated and even ribbon-like, with smooth outlines and shal low depressions. Most nuclei display extreme convolution and even segmentation. There are large and deep infold-
Prof. A. Bourlond Department of Dermatology. Faculty of Medicine Catholic University of Louvain 52. avenue Li. Mourner Tour Vesalc B-1200 Brussels (Belgium)
© 1992 Karger AG. Basel 1018-8665/92/1854-0291 S 2.75/0
Downloaded by: Univ. of California Santa Barbara 128.111.121.42 - 3/6/2018 9:48:24 AM
A . Bourlond C. Marcoux
Fig. 1. Typical labyrinthic nucleus showing nuclear bridges (arrow) and pseudoinclusions (asterisk), x I8.(X)0.
Fig. 2. Intricate nuclear bridges (arrow) and pseudoinclusions (asterisk) are highly characteristic of the hyperconvoluted and hypersegmented nucleus, x 37.000.
292
Bourlond/Marcoux
ments, channels and bridges as well as cytoplasmic pscu doinclusions and pseudo-pseudoinclusions lead to the con struction of hyperconvoluted, hypersegmented. labyrinthic nuclei (fig. 2). Chromatin, of low density, condenses slightly beneath the nuclear membrane. Mitoses are occasional; nuclear pores remain scarce; the perinuclear cisterna is absolutely clear but of varying width. The nucleolus is apparently nor mal or quite large and muriform. In somes instances, it is localized at the level of symmetrical infolding and adheres to the opposite inner side of the nuclear membrane (fig. 3). Nuclear or virus-like inclusions, as described by Hcntzcr and Kobayasi [l], develop occasionally.
Dermatofibrosarcoma protuberans
Downloaded by: Univ. of California Santa Barbara 128.111.121.42 - 3/6/2018 9:48:24 AM
ings of the nuclear membrane with constitution of the socalled cytoplasmic pscudoinclusions (fig. I). There are many outward projections of the nuclear membrane with or without ampullar dilatation; narrow ones deserve the deno mination of nuclear channels. Quite often adjacent mem branes come into close contact and constitute nuclear bridges; there is a dark central line (apposition if not fusion of the nuclear limiting zone), two adjacent thin lines (nuclear membrane), perinuclear cisterna and its cytoplas mic membrane. Sometimes adjacent projections isolate cytoplasmic areas, which are considered by contrast as pseudo-pseu doinclusions. Multiplication of nuclear projections, seg
Fig. 3. a Large nucleolus seals the nuclear space between opposite infold ing of the plasmalemma. x 19.000. b Some tumor cells contain a well developed cilium associated with the Golgi apparatus, x 24.000.
Cytoplasm Most of the cells arc elongated, they develop in ribbon like slender processes. Generally, cells and extensions are established in somewhat laminated and parallel bundles. Plasmalemma appears smooth and wavy and supports only pinocytic vesicles in a low number. Very discrete condensation of extracellular amorphous or finely granular material is observed here and there along the membrane. Never impressive or regular, it can hardly be considered as a primitive basement membrane (fig. 4). Close contacts of adjacent cells in the way of tight junctions are exceptional. Cytoplasm is scanty and densities slightly around the nucleus. It shows few profiles of rough surfaced endoplasmic reticulum. Golgi apparatus is never developed; mitochondrias arc few but dilated. Dense bodies remain inconspicuous. Vacuoles and lipid inclusions exist only in some areas. Quite often in the first case, but rarely in the sec ond case, there are centrioles and even cilia at various stages of development (fig.3). Filaments are few, dispersed or loosely tight in tiny bundles, without densification and with out evident adherence plaques to the cell membrane - a fea ture quite distinct from that of smooth muscle cells.
293
Downloaded by: Univ. of California Santa Barbara 128.111.121.42 - 3/6/2018 9:48:24 AM
Fig. 4. a Capillary showing normal-looking endothelial (E) and pcrithelial (P) cells; outside of it. another cell might be considered ‘transitional’, x 11.2(H). b Tumor cells with a labyrinthic nucleus pre sent sometimes dark inclusions and 'basement membrane-like' mate rial (arrow), x 16.500.
Discussion Labyrinthic nuclei have already been described in detail by Aubôck [2]; they appear quite common in DFP [2. 3] and giant cell fibroblastoma [4]. However, they have been observed also in other aggressive fibroblastic proliferations [2, 3] and low-grade malignant tumors with low mitotic index [4], The nuclear appendages, the so-called nucleotesimals, might represent a peculiar type of amitosis [5]. The present observation does not provide any clues in favor of the melanocytic origin (or participation); even in desmoplastic melanotic lesions, melanosomes ought to be seen even in low number. The finding of melanocytes in one instance [6] remains puzzling. Labyrinthic nuclei, almost nonexisting basement mem brane, poorly structured lamellar extensions of the cyto plasm. absence of pseudocorpuscular bodies, extreme dis persion if not absence of nerve fibers, exceptionally long spacing collagen fibrils represent cumulative evidence against the neural theory; Fisher and Vuzevski [7], as well as Zina and Bundino [8]. reach similar conclusions. On the other hand, Hashimoto et al. [6] note a great number of long spacing collagen fibrils and Alguacil-Gar d a et al. [9] hold that tumor cells have marked ultrastruc tural similarities with the perineural cells. Such discrepancies result most probably from the level and quality of differentiation of tissues and the poor relia bility of microscopic samples. Histiocytic proliferations may be doubted; in such instances, cells appear more globular and loaded with a
294
B outiond/M arcoux
larger amount of lipid and phagocytic inclusions and pos sibly Langerhans granules. Alguacil-Garcia et al. [9] dis card also this hypothesis; on the contrary, Ozzcllo and Hamels [10] and Yoshida ct al. [II] present impressive arguments from their observations of cultured tumoral tis sues but technical procedures might have modified the met abolic behavior of cells. A pure fibromatous tumor does not fit easily, even if Zina and Bundino [8] and Escalona-Zapata ct al. [12] accept the fibroblastic nature of the tumor cells. The colla gen content is too low, even for myxoid stroma, and the cytoplasm does not appear really active as commonly observed in young fibroblasts. The pilo-angioleiomyoma origin appeals at first but proves definitively unacceptable: there arc no characteristic smooth muscle cells, myofibril lar differentiation, axial localization of organelles, base ment membrane or satellite nerve fibers. It might be hypothesized that perithelial cells, heavily irritated, might participate as transitional elements; it seems more sensible to consider them as comparse pcrithelial cells, parallel to the circumference of the vessels, provided with slender and clear cytoplasm, loaded with few organelles and con voluted nucleus. It must be stressed that tumor cells never impinge upon the vessel wall and do not blend with the perithelial apparatus; on the contrary, a thick layer of amorphous or microfibrillar material separates them clearly. The myofibroblast has been proposed as a reactive fibroblast [13-16]; its main characteristics arc: elongated nucleus with infoldings, ribbon-like cytoplasm with a lot of organelles and bundles of (myo)-filaments, pinocytic vesi cles, tight junctions and some basement-like material. Even if considered as a hypothetical cell, it nevertheless represents a highly convenient tool to look at fibroblastic hyperplasias and tumors [17-19], A reappraisal of the functions and histochemical pro perties of such a cell in scleroderma has been recently pre sented by Sappino et al. [21]. Even if it has been described with a larger component of organelles and filaments, the myofibroblast fits as the stem cell of DFP. if we accept that it loses part of its character istics while engaged in intense or wild proliferation. At least, striking similarities make this hypothesis the most appealing one. Schmoeckel ct al. [20] propounded the fibroblastic nature at large of dermatofibrosarcoma protuberans; nevertheless they added, interestingly enough, that ‘the presence of basal membranes and intracytoplasmic filaments in case 6 suggested that myofibroblasts were the origin of this tumor’. Further enzymatic and immunological studies are needed to ascertain this theory.
Dermatofibrosarcoma protuberans
Downloaded by: Univ. of California Santa Barbara 128.111.121.42 - 3/6/2018 9:48:24 AM
Intercellular Space It is characterized by amorphous material, tangles of collagen fibrils and fibers, exceptionally long spacing colla gen fibers or Luse bodies. Unmyelinated fibers, quite rare and devoid of perineural sheath, do not come into contact with the tumor cells. Melanocytes, mast cells, Langerhans cells are definitively absent; inflammatory cells and histio cytes arc exceedingly rare. Especially in the second case, capillaries proliferate. Their lumen stays wide open but is often filled with erythrocytes. Turgescent endothelial cells contain numerous organelles such as Wcibcl-Paladc cigar bodies and filaments. Prominent pcrithelial cells contain a high-density cyto plasm and a large dark nucleus. Pcripherically to these cells, there are others that might be considered transitional because they show elongated and wavy outline, moderate load of organelles, indented nucleus, segmental basement membrane (fig.4). Their significance is discussed below.
References 9 Alguacil-Garda A. Unni K. Goellncr JR: Histogenesis of dermatofibrosarcoma protube rans. An ultrastructural study. Am J Clin Pathol 1978;69:427-434. 10 Ozzello L. Hamels J: The histiocytic nature of dermatofibrosarcoma protuberans. Tissue cul ture and electron microscopy study. Am J Clin Pathol 1976:65:136-148. 11 Yoshida H. Malsui K. Hashimoto K. Yumoto T. Mihara M: Dermatofibrosarcoma protube rans and its tissue culture study. Acta Pathol Jpn 1982:32:83-91. 12 Escalona-Zapata J. Fernandez EA. Escuin FL: The fibroblastic nature of dermatofibrosar coma protuberans. A tissue culture and ultrastructural study. Virchows Arch 1981:391: 165-175. 13 Gabbiani G. Ryan GB. Majno G: Presence of modified fibroblasts in granulation tissue and their possible role in wound contraction. Experientia 1971:27:549-550. 14 Gabbiani G. Majno G: Dupuytren’s contrac ture: Fibroblast contraction? An ultrastruc tural study. Am J Pathol 1972:66:131-146. 15 Roland J : Fibroblaste et myofibroblaste dans le processus granulomateux. Ann Allât Pathol (Paris) 1976:21:37-44.
16 Ryan GB. Cliff WJ. Gabbiani G. Irle C, Monlandon D. Statkov PR. Majno G: Myofibro blasts in human granulation tissue. Hum Pathol 1974:5:55-67. 17 Bhawan J. Bacchetta C. Joris I. Majno G: A myofibroblastic tumor. Infantile digital fibroma (recurrent digital fibrous tumor of childhood). Am J Pathol 1979:94:19-36. 18 Kalcnkamp D. Stiller D: Cellular composition of the so-called dermatofibroma (histiocytoma cutis). Virchows Arch 1975;367:325-336. 19 Wirman JA: Nodular fasciitis, a lesion of myo fibroblasts. An ultrastructural study. Cancer 1976.38:2378-2389. 20 Schmoeckcl C. Albini A. KriegT. Stets R: The fibroblastic nature of dermatofibrosarcoma protuberans: Morphological investigations in vivo and in vitro. Arch Dermatol Res 1985; 278:138-147. 21 Sappino AP. Masouye I. Saurat JH. Gabbiani G: Smooth muscle differentiation in scler oderma fibroblastic cells. Am J Pathol 1990: 137:585-591.
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1 1ionizer B. KobayasiT: Nuclear bodies in cells of normal human skin. Acla Derm Venercol 1976:56:429-434. 2 Auböck L: Zur Ultrastruktur fibröser und histiocytärer Hauttumoren (Dermatofibrom. Dermatofibrosarcoma protuberans. Fibroxanthom und Histiocytom). Virchows Arch 1975;368:253-274. 3 Auböck L: 'Labyrinthkerne' bei einem Der matofibrosarcoma protuberans und einem Fibroxanlhom. F.xp Pathol 1976;12:1-18. 4 Shmooklcr li. Enzingcr F. Weiss S: Giant cell Hbroblastoma. Cancer 1989;64:2154-2161. 5 Elias II. Fong BB: Nuclear fragmentation in colon carcinoma cells. Hum Pathol 1978:9: 679-684. 6 Hashimoto K. Brownstein MH. Jakobiec FA: Dermatofibrosarcoma protuberans. A tumor with perineural and endoneural cell features. Arch Dermatol 1974:110:874-885. 7 Fisher ER. Vuzcvski VD: Cylogenesis of schwannoma (neurilemoma), neurofibroma, dermatofibroma, and dermatofibrosarcoma as revealed by electron microscopy. Am J Clin Pathol 1968:49:141-154. 8 Zina AM. Bundino S: Dermatofibrosarcoma protuberans. An ultraslructural study of five cases. J Cutan Pathol 1979:6:265-271.
