1/23. Angiomyofibroblastoma and aggressive angiomyxoma: two benign mesenchymal neoplasms of the female genital tract. An immunohistochemical study.We describe a rare case of angiomyofibroblastoma (AMF) of the vulva and one case of aggressive angiomyxoma (AAM) of the pelvic region and, with the help of an extensive revision of the literature, we attempt to define their histogenesis and peculiar biological behaviour by an immunohistological evaluation. Our results indicate that AAM, which is characterized by the presence of a high content of glycosaminoglycans in the stroma, expresses uniformly vimentin and hyaluronate receptor CD44, and heterogeneously muscle specific actin (MSA) and desmin, while AMF displays a positive reaction for vimentin, desmin and laminin, and only a weak and heterogeneous positivity for CD44. Both AMF and AAM showed no immunohistochemical reactivity for alpha-smooth muscle actin (ASMA), myoglobin, cytokeratin, collagen type iv, CD68 and S-100. The stromal cells of AAM were negative for laminin. These findings support the suggestion of an origin of the two entities by a common myofibroblastic progenitor, which normally occurs in the lower female genital tract and subsequently undergoes a neoplastic transformation. The expression of CD44 by AAM, which has never been reported before, could be responsible for its more aggressive behaviour, because this receptor is able to mediate migration of neoplastic cells on a hyaluronate rich extracellular matrix. It is speculated that the neoplastic cell of the AAM and AMF of the vulva is a specific myofibroblast which probably arises from undifferentiated mesenchymal cells normally occurring in the lower female genital tract.- - - - - - - - - - ranking = 1keywords = stromal (Clic here for more details about this article) |
2/23. Low-grade fibromyxoid sarcoma: clinicopathologic case report with review of the literature.Low-grade fibromyxoid sarcoma is a rare, benign-appearing soft tissue neoplasm with an aggressive clinical course characterized by multiple local recurrences over several years, with ultimate spread to lung and occasionally to bone. Thus far, a total of 24 cases of low-grade fibromyxoid sarcoma have been reported in the literature. The authors present an additional case that grossly and microscopically emphasizes a pronounced lobular pattern of contrasting areas of cellularity showing high proliferative activity, as demonstrated by a proliferation marker, Ki 67 with MIB-1, and hypocellular areas with prominent myxoid component and abundant collagen fibrils. There was predominance of delicate capillary-sized stromal vessels with collagenized walls in both cellular and myxoid areas. The unusual features in this case were osseous metaplasia, prominent intranuclear pseudoinclusions, dna tetraploidy, and membrane-bound intracytoplasmic fat vacuoles. The immunoprofile and cytologic and ultrastructural features are described. After the excision of the tumor, the patient was treated with radiotherapy without chemotherapy. The patient has been observed for 26 months and is alive without the evidence of disease. The postoperative follow-up with axial computed tomography at 24 months showed no evidence of disease, except postsurgical fibrotic changes.- - - - - - - - - - ranking = 1keywords = stromal (Clic here for more details about this article) |
3/23. Pelvic malignant mixed mesodermal tumor of uncertain origin: a case report.Extra-uterine, and especially extragenital, malignant mixed mesodermal tumors (MMMT) are very rare. A large intrapelvic tumor resected from a 56-year-old woman was investigated with morphological and immunohistochemical methods. A large, soft and fragile tumor was located in the pelvic space. The tumor showed high cellularity and was biphasic; it consisted of an admixture of adenocarcinoma and various kinds of sarcomas. The latter were comprised of high-grade endometrial stromal sarcoma, pleomorphic sarcoma, and chondrosarcoma. The pleomorphic sarcoma showed a storiform pattern. The periodic acid-Schiff-positive eosinophilic hyaline droplets and globules in multinucleated giant cells revealed a typical ring-like or peripheral staining for alpha-1-antitrypsin and alpha-1 antichymotrypsin. We considered this case to be pelvic MMMT of uncertain origin, heterologous type.- - - - - - - - - - ranking = 71.055783431848keywords = endometrial stromal, stromal (Clic here for more details about this article) |
4/23. Angiomyomatous hamartoma and associated stromal lesions in the right inguinal lymph node: a case report.Angiomyomatous hamartoma is a rare disease with a predisposition for the inguinal lymph nodes. A 51-year-old male patient visited a local hospital because of a right inguinal mass, measuring 3 x 4 cm in size, which was resected. The resected specimen showed irregularly distributed thick-walled vessels in the hilum, extending into the medulla and focally into the cortex of the node, eventually becoming more dispersed and associated with smooth muscle cells splaying into sclerotic stroma. These findings are compatible with an angiomyomatous hamartoma. Another tumor-like mass appeared shortly after the resection at the same location, but was not an angiomyomatous hamartoma, rather it was composed of edematous stromal tissue with proliferating smooth muscle cells. The stromal component included thick-walled blood vessels and lymphatics. Although it could not be determined whether these associated changes in the surrounding stroma are a cause or an effect of angiomyomatous hamartoma, they indicate the clinical difficulty in determining an appropriate area of resection and may provide clues to the pathogenesis of angiomyomatous hamartoma.- - - - - - - - - - ranking = 6keywords = stromal (Clic here for more details about this article) |
5/23. Endometrial stromal sarcoma: objective response to letrozole.BACKGROUND: Low-grade endometrial stromal sarcoma is generally an indolent tumor rich in estrogen and progesterone receptors. Objective responses to hormonal therapy, most commonly with megestrol acetate, have been reported. CASE: The patient is a 51-year-old woman who presented with low-grade endometrial stromal sarcoma confined to the uterus in 1991 and was treated with total abdominal hysterectomy and bilateral salpingo-oophorectomy. Approximately 5 years later, the patient had recurrent pelvic disease treated with radiation therapy, followed by an attempt at resection. She was treated with megestrol acetate during the period she received radiation therapy with poor tolerance. tamoxifen was then given with no tumor response. megestrol acetate was restarted with progression of disease in the pelvis and abdomen. Letrozole was then given at a daily dose of 2.5 mg with partial response for a duration of 9 months. CONCLUSION: Letrozole at a daily dose of 2.5 mg may be effective in low-grade endometrial stromal sarcoma with positive estrogen receptors.- - - - - - - - - - ranking = 217.16735029554keywords = endometrial stromal, stromal (Clic here for more details about this article) |
6/23. Metastatic epithelioid gastrointestinal stromal tumor: yet another tumor with anemone cell features.Since 1980 when Sibley and coworkers first described a nodal neoplasm of unknown histogenesis with striking surface microvilli for which they introduced the term "anemone cell," a series of reports have appeared in the literature illustrating tumors with similar ultrastructural features. While most reported cases showed differentiation along a particular line, rare cases remained histogenetically unclear. In this report a case is described of epithelioid gastric gastrointestinal stromal tumor metastatic to the liver, showing conspicuous long microvillus-type cell processes partially or circumferentially coating the cell surfaces, thus qualifying as yet another tumor type with anemone cell features.- - - - - - - - - - ranking = 5keywords = stromal (Clic here for more details about this article) |
7/23. Gastrointestinal stromal tumor presenting as a pelvic mass.gastrointestinal stromal tumors (GISTs) are c-kit-positive tumors that may arise anywhere in the tubular gastrointestinal tract. Around 5% of the cases arise elsewhere in the abdominal cavity. Tumors originating in the omentum and mesentery have been reported.A 31-year-old woman presented with pelvic pain, a palpable pelvic mass, and elevated CA-125. Imaging showed innumerable pelvic and abdominal masses. Histopathology showed a GIST that was positive for c-kit and vimentin and negative for desmin and smooth muscle actin. The patient was started on imatinib mesylate. Six months after diagnosis the tumor has remained stable.GI stromal tumors (GIST) may initially present as pelvic mass with elevated CA-125. Imatinib mesylate is the current mainstay therapy for GISTs after surgery.- - - - - - - - - - ranking = 6keywords = stromal (Clic here for more details about this article) |
8/23. Aggressive angiomyxoma. A report of four cases occurring in men.Aggressive angiomyxoma is a distinctive, locally aggressive but nonmetastasizing soft tissue tumor of the pelvic soft tissues and perineum. This rare tumor occurs almost exclusively in adult women. We report four cases occurring in adult men, one each located in the scrotum, inguinal region, spermatic cord, and pelvis. The tumors were infiltrative, and were composed of fibromyxoid matrix sparsely populated by bland-looking spindled and stellate cells with delicate cytoplasmic processes. There were haphazardly scattered small and large blood vessels, some of which exhibited hypertrophy or hyalinization of the wall. Immunohistochemically, the stromal cells stained consistently for vimentin and variably for muscle-specific actin, but not alpha-smooth muscle actin, desmin, and S-100 protein. None of the four tumors recurred in follow-up times from 11 months to 6 years, although two previously reported cases in men recurred. This uncommon tumor occurring around the genital region in men merits wider recognition because of its potential for recurrence. It should be distinguished from benign tumors with low risk of recurrence on one hand, and from malignant myxoid tumors with metastatic potential on the other.- - - - - - - - - - ranking = 1keywords = stromal (Clic here for more details about this article) |
9/23. An unusual case of ectopic or "parasitic" leiomyoma excised by laparoscopic surgery.A 47-year-old woman underwent a laparoscopic resection of a large ectopic or "parasitic" fibroid filling the pelvis and placed within the rectosigmoid mesentery. The tumor was excised completely without a need for hysterectomy. Immunohistochemical and ultrastructural studies confirmed a "parasitic" leiomyoma, excluding sarcoma or a gastrointestinal stromal tumor. Because of its bizarre location in relation to the large bowel, a combined general surgical and gynecological approach was used successfully. The pathology of this rare tumor is reviewed.- - - - - - - - - - ranking = 1keywords = stromal (Clic here for more details about this article) |
10/23. The value of c-kit mutational analysis in a cytokeratin positive gastrointestinal stromal tumour.The expression of cytokeratins in gastrointestinal stromal tumours (GISTs) is rare and may lead to diagnostic confusion when it occurs. This report describes a metastatic GIST that stained strongly for cytokeratins, CD117, and CD34 in a patient who was previously diagnosed with gastric epithelioid angiosarcoma. A review of both tumours showed the same histological and immunohistochemical profiles, and c-kit molecular analysis revealed an insertional mutation at codon 558 of exon 11 in both tumours. Thus, pathologists should be aware that GISTs can occasionally express cytokeratins, and that c-kit mutational investigations may have a key diagnostic role and may prevent diagnostic mistakes that could have important clinical implications.- - - - - - - - - - ranking = 35.354038263571keywords = stromal tumour, stromal (Clic here for more details about this article) |
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