Intracellular "fibrous long spacing" collagen in morbus dupuytren (Dupuytren's contracture)

Ultrastructural study of a perineurioma with ribosome-lamella complexes

The participation of the perineurial cell in peripheral nerve tumors is the subject of much debate. The case of a 75-year-old female with a soft tissue tumor on her left shoulder is presented. The tumor had histological, ultrastructural, and immunohistochemical characteristics of a pure perineurial cell neoplasm. Ultrastructurally, distinctive ribosome-lamella complexes were found in the cytoplasm of the perineurial cells. This may be the first time that these structures have been described in perineurioma.

Clinical and cellular effects of colchicine in fibromatosis

The proliferating cells in fibromatoses are myofibroblasts that produce abundant stromal collagen and contain intracellular native and widely spaced collagen fibers. To assess the clinical and cellular effects of colchicine in such tumors, this drug was administered to three patients, one with musculoaponeurotic desmoid fibromatosis, one with Dupuytren's palmar fibromatosis, and one with Peyronie's disease. All three patients had an excellent clinical response, with reduction of tumor size and improvement of contracture. Two cases were studied ultrastructurally; the main cellular changes detected were collapse of the rough endoplasmic reticulum cisternae, reduction of myofilaments, and disappearance of intracellular widely spaced collagen. The findings from this study indicate another probable application for colchicine and support the concept that collagen fibers can be formed intracellularly.

Soft tissue tumor with prominent leptomeric fibrils and complexes

A recurrent soft tissue tumor from the groin in a 37-year-old male is described. The tumor cells contain many leptomeric structures, both fibrils and complexes, but none of the other characteristic features of striated muscle: alternating parallel thick and thin myofilaments with Z-line material. A review of one rhabdomyoma and six rhabdomyosarcomas demonstrates that leptomeric structures are present in large amounts in the rhabdomyoma but are very infrequent in only three of the six rhabdomyosarcomas. A careful search for leptomeric structures is indicated when the ultrastructural diagnosis of either rhabdomyoma or rhabdomyosarcoma is being considered.

Dupuytren type fibromatoses. A clinicopathologic study of 62 cases

This clinicopathologic study concerns 62 patients with one of the Dupuytren type fibromatoses. Of the 62 patients, 42 had the lesion in the palm (palmar fibromatosis), 12 in the sole (plantar fibromatosis), 2 in the penis (penile fibromatosis), and 6 in the ectopic locations, the dorsal aspect of the hand in 3 patients, the dorsum of the fingers in 2, and the forearm in 1. The clinically palpable nodules were histologically classified into those of the following three phases, according to LUCK'S classification: proliferative phase (27), involutional phase (23), and residual phase (12). In addition to fibroblastic proliferation, the lesion of the proliferative phase exhibited vascular features consisting of one or more layers of cells with oval nuclei around the vessels within the nodule. In the lesions of the late proliferative and involutional phase, the intracytoplasmic fine filaments were visible in cells compatible with myofibroblasts by Masson's trichrome stain. The nuclei of the elemental fibroblasts in the same phases were often crossed transversely by one or more fine basophilic lines.

Intracellular collagen fibers in the capsule around silicone expanders in guinea pigs

Ultrastructural studies of fibrous capsules surrounding silicone tissue expanders in guinea pigs revealed a number of fibroblasts containing collagen fibers inside cytoplasm with typical periodicity. These fibers were single or multiple, appeared straight, coiled, or bent, and lay in narrow, undulating membrane spaces. These intracellular collagen fibers were found in as many as 15% of the cells in capsules between 7 and 12 weeks of expansion. These observations suggest that during capsule development there is some imbalance between the synthesis of collagen fibers and their degradation. It is possible that increased synthesis of collagen fibers as well as their phagocytosis by fibroblasts may exist simultaneously.

Multiple cutaneous fibromyxomas: a light and electron microscopic study

A 27-year-old woman developed many nodular lesions, ranging in diameter from 3 mm to 15 mm and clinically indistinguishable from dermatofibromas. Light microscopic examination showed large amounts of mucin, fibroblasts and histiocytes throughout the dermis. Electron microscopic study revealed wide electron lucent areas and long branching winding electron dense threads occupying the ground substance. While dilated cisternae of endoplasmic reticulum containing a finely granular material characterized the fibroblasts, banded structures, intracellular collagen and myelinoid figures were prominent in the histiocytes. The term fibromyxoma is introduced to designate this tumor.

Palmar fibromatosis-"Dupuytren's contracture". A comparison of light electron and immunofluorescence microscopic findings

A comparison of light, immunofluorescence and electron microscopic findings in palmar fibromatosis (Dupuytren's disease) revealed that the three morphologic phase of Luck; I. proliferative, 2. involutional, and 3. residual, corresponded for the most part to I. fibroblastic, 2. myofibroblastic or 3. fibrocytic lesions, respectively. The spectrum between proliferative phase and residual phase appeared immunohistochemically as a decrease in collagen type III, and an increase of collagen type I. Myosin was found in substantial quantities only during the involutional phase, distinguished by myofibroblasts, presumably with contractile capabilities. Thus, the clinical presence of contractures with palmar fibromatosis might also be explained in the absence of distinct fiber formation.

The ultrastructure of mycobacterium marinum granuloma in man

3 biopsies of 3-5 week-old nodular lesions in 2 patients with so-called swimming-pool (aquarium-) granuloma have been examined by electron microscopy. The cytohistological spectrum simultaneously comprises acute exudative as well as chronic proliferative phenomena. Epithelioid cells and collagen producing fibroblasts are already conspicious in 3 week-old granuloma. According to the cytological composition the Mycobacterium marinum granuloma represents a high-turnover granuloma with immunogenic origin. It is comparable to mycobacterial diseases in the presence of well developed cell mediated immunity (Lupus vulgaris, tuberculoid leprosy). Degrading mycobacteria have been rarely detected in phagocytes and are compared with viable bacilli in macrophages of experimentally infected mice. Curved and annular parallel membranes ("worm-like structures") in the cytoplasm of transformed macrophages and in fibroblasts presumably originate from the membranes of endoplasmic reticulum. Cord-like structures with transverse bands (periodicity 170-180 A) in the lumen of RER of some fibroblasts are interpreted as intracellularly aggregated collagen precursors.

Occurrence of myofibroblasts in the different phases of morbus Dupuytren (Dupuytren's contracture)

Twenty-one surgically removed specimens of Morbus Dupuytren (M. D.) were studied by light and electron microscopy. The cell type observed in the proliferative phase shows the basic ultrastructural features of fibroblasts, while the majority of the cells in the involutional phase resemble myofibroblasts. Myofibroblasts exhibit ultrastructural characteristics of both smooth muscle cells and fibroblasts and are said to behave functionally like smooth muscle cells. In the residual phase, typical fibrocytes of connective tissue are found. These findings confirm the concept that fibroblasts are capable of converting into myofibroblasts and demonstrate the myofibroblasts represent an intermediate cell type of transitional cellular differentiation. The significance of myofibroblasts for the development of the contracture of M. D. is discussed.