Intranodal palisaded myofibroblastoma with overexpression of cyclin D1

Parotid's Intranodal Palisaded Myofibroblastoma: A Very Rare Tumour

Intranodal palisaded myofibroblastoma is a rare benign tumor of the lymph nodes, that arises from smooth muscle cells or myofibroblast, chiefly in the inguinal lymph nodes. Intranodal palisaded myofibroblastoma of the parotid gland is exceedingly scarce, even more, its recurrent characteristic; which underlines the grave importance of a long, strict monitoring and surveillance plan. Alongside these salient points in this unusual case, we also aim to highlight the peculiar difficulties inevitably faced, given the unfortunate lack of typical pathognomonic clinical and radiological features. We therefore, report a rare case of recurrent intranodal palisaded myofibroblastoma, arising in the felt parotid gland in a 53-year-old male patient, diagnosed by anatomopathological and immunopathological analysis. Described as benign tumor intranodal palisaded myofibroblastoma is a scarce myofibroblastic neoplasm of the lymph nodes. Histological and immunopathological features represent the determining factors for the diagnosis, of this favorable prognosis tumor.

Intranodal Palisaded Myofibroblastoma in a Submandibular Lymph Node

Intranodal palisaded myofibroblastoma (IPM), also known as "intranodal hemorrhagic spindle cell tumor with amianthoid fibers," is a rare benign mesenchymal tumor originating from smooth muscle cells and myofibroblasts, often with the presence of amianthoid fibers. Usually IPM affects inguinal lymph nodes, but three cases have been described in the submandibular and cervical lymph nodes. We report a new case of a 44-year-old women with submandibular mass. Cervical ultrasound showed a suspect right submandibular adenomegaly. The patient underwent an excision of the submandibular mass. Histological features of the tumor include an encapsulated fusocellular proliferation, with nuclear palisading, amianthoid fibers, hemosiderin pigment, and extravasated erythrocytes. In the light of these results, we made the diagnosis of IPM. No recurrence was found 5 years after surgery.

Lymph node stromal and vascular proliferations

The recognition and reporting of stromal and vascular lesions of the lymph node is rife with difficulties including relative rarity, a lack of familiarity with lesions and the challenges of using ancillary studies appropriately. In this manuscript, we highlight a range of benign stromal and vascular abnormalities that can be identified in nodal specimens.

Intranodal Palisaded Myofibroblastoma: Radiological and Cytological Overview

Background

Intranodal palisaded myofibroblastoma is a benign and very rare mesenchymal neoplasm of the lymph nodes originating from differentiated smooth muscle cells and myofibroblasts.

Case Report

We report a case of intranodal palisaded myofibroblastoma in an 84-year-old woman with Parkinson’s disease that presented as a left inguinal mass. The diagnosis was made using ultrasound-guided fine needle aspiration biopsy and consequent cytopathological examination that included immunohistochemical analysis. Herein, we discuss the presentation of a rare intranodal palisaded myofibroblastoma with emphasis on its ultrasonographic and cytopathologic features.

Conclusions

Intranodal palisaded myofibroblastoma should be considered in the differential diagnosis of inguinal lymphadenopathy and the diagnosis is possible with cytopathologic exam and immunohistochemical analysis using ultrasound-guided FNA biopsy, guiding the clinician to nodal excision rather than aggressive measures.

Intranodal palisaded myofibroblastoma: a case report from an unusual site

Intranodal palisaded myofibroblastoma is a rare lymph node benign tumor, of unknown pathogenesis. Although benign, this lesion is frequently confused with metastatic lesions, especially in atypical sites. We report a 39-year-old man with a history of testicular malignant mixed germ cell tumor, presented with abdominal painless mass. The computed tomography of the abdomen confirmed the presence of 180 × 140 mm2 mass in the retroperitoneum with lympadenopathy on the right measuring 20 x 15 mm. The patient underwent exploratory laparotomy, and a surgical exerese of the retroperitoneeum lymph node was made. Histological and immunohistochemical examination confirmed the diagnosis of intranodal palissaded myofibroblastoma. This entity has been previously described, only once, in retroperitoneal region. Despite to the rarity of this neoplasm, we discuss clinicopathologic features and differential diagnosis.

Diagnostic clues for FNA diagnosis of intranodal palisaded myofibroblastoma, a rare benign lesion, an introspective case report

Intranodal palisaded myofibroblastoma (IPM) is a benign entity, characterized by intranodal proliferation of cells of myofibroblastic origin. It has five distinct histologic features: compressed remnants of lymphoid tissue at the periphery, spindle cells with nuclear palisading, intralesional hemorrhage, amianthoid fibers, and intracellular and extracellular fuchsinophilic bodies. The spindle cells are SMA and vimentin (IHC) positive and are negative for S 100, and has a low proliferative index. Cytologic diagnosis of this lesion is a diagnostic challenge and has to be differentiated from other stroma rich lesions including schwannoma. The FNA smears were reviewed after histopathology to look for any specific features. This report highlights the variable character of spindle cells, presence of unique "amanthiod fibers" and blood vessel within cell clusters in MGG stained FNA smears, which can be a useful diagnostic clue. This observation is being reported for the first time.

Intranodal palisaded myofibroblastoma: another mesenchymal neoplasm with CTNNB1 (β-catenin gene) mutations: clinicopathologic, immunohistochemical, and molecular genetic study of 18 cases

Intranodal palisaded myofibroblastoma is a benign, lymph node-based myofibroblastic tumor of unknown pathogenesis. We report the clinicopathologic, immunohistochemical, and molecular genetic features of this rare entity. The study cohort consisted of 14 men and 4 women ranging in age from 31 to 65 (mean, 47; median 49) years with tumors arising in inguinal lymph nodes (n=15), a neck lymph node (n=1), and undesignated lymph nodes (n=2). Most individuals presented with a painless mass or lump. Possible trauma/injury to the inguinal region was documented in 4 cases. Tumors ranged in size from 1.0 to 4.2 (mean, 3.1; median; 3.0) cm. Microscopically, the process presented as a well-circumscribed, oftentimes pseudoencapsulated nodule (n=17) or nodules (n=1). Tumors consisted of a cellular proliferation of cytologically bland, spindled cells arranged in short fascicles and whorls within a finely collagenous (n=11) or myxocollagenous (n=7) matrix. In 12 tumors, scattered fibromatosis-like fascicles of spindled cells were noted. Histologic features characteristic of the process included nuclear palisades (n=16 cases), collagenous bodies (n=15), and perinuclear intracytoplasmic hyaline globules (n=10). Mitotic activity ranged from 0 to 8 (mean, 2; median, 1) mitotic figures/50 high-powered fields with no atypical division figures identified. Immunohistochemically, all tumors tested expressed smooth muscle actin and/or muscle-specific actin (n=5, each), and nuclear β-catenin and cyclin D1 (n=8, each). The latter 2 results prompted a screening for mutations in the β-catenin gene glycogen synthase kinase-3 β phosphorylation mutational "hotspot" region in exon 3 using polymerase chain reaction amplification and Sanger sequencing. Single nucleotide substitutions leading to missense mutations at the protein level were identified in 7 of 8 (88%) analyzed tumors and are responsible for the abnormal expression of β-catenin and cyclin D1. These results demonstrate that mutational activation of the β-catenin gene is likely a pivotal event in the pathogenesis of intranodal palisaded myofibroblastoma.

Axillary intranodal palisaded myofibroblastoma: report of a case associated with chronic mastitis

Intranodal palisaded myofibroblastoma is a rare tumour of the lymph node that may be derived from myofibroblasts. The most usual area of presentation is the inguinal lymph nodes, but occurrence within other areas has also been reported. It is characterised by spindle cells, amianthoid-like fibres, and by the proliferation of hemosiderin-containing histiocytes in the lymph node. Although intranodal palisaded myofibroblastoma is benign, it is frequently confused with metastatic lesions, especially when it occurs in atypical sites. We herein report the second case of axillary intranodal palisaded myofibroblastoma occurring in a woman with a granulomatous chronic mastitis. The salient clinicopathological features of this unusual tumour are presented with emphasis to the pathogenesis of the tumour as well as to its histological and immunohistochemical characteristics. Clinicians and pathologists must be aware of this rare tumour to avoid a misdiagnosis of malignancy and assure patient a correct therapeutic management.

Intranodal palisaded myofibroblastoma: a review of the literature

Intranodal palisaded myofibroblastoma is a rare benign primary mesenchymal neoplasm originating from differentiated smooth muscle cells and myofibroblasts. The precise etiology and pathogenesis has not been adequately explained as yet. Very few series and cases have been reported in the literature. Though inguinal region is the commonest site of this rare tumor, but the tumor at other diverse sites have been reported. Because of its rarity, it can be often misdiagnosed and confused with other disorders and more commonly with metastasis. We report an extensive review of literature about intranodal palisaded myofibroblastoma--its characteristics, presentations, features, and management.

Vaginal superficial myofibroblastoma: a rare mesenchymal tumor of the lower female genital tract and a study of its association with viral infection

Superficial myofibroblastoma is a rare mesenchymal tumor in the lower female genital tract. The exact etiology of superficial myofibroblastoma remains unclear. The association of viral infection and mesenchymal tumors has been well established in some particular types of soft tissue tumors. In the lower female genital tract, the intimate correlation of viral infection and tumor pathogenesis has been also proposed. We present a 59-year-old woman with postcoital bleeding for 1 month. The pelvic examination revealed a 2-cm polypoid mass mimicking leiomyoma at the vaginal fornix. Local excision was performed, and the pathological examination revealed a superficial myofibroblastoma. No tumor recurrence was noted during the 12-month follow-up. Pathological differential diagnosis of this tumor from other mesenchymal tumors is essential because of its distinct clinicopathological features. Furthermore, fluorescence in situ hybridization of human papilloma virus (HPV) and Epstein-Barr virus (EBV), as well as immunohistochemical staining of human herpesvirus 8 (HHV8), was negative in tumor cells. To the best of our knowledge, we are the first group to study the possible relationship of viral infection and the occurrence of this mesenchymal tumor. Our results suggested no association of vaginal superficial myofibroblastoma and infection with HPV, EBV, or HHV8.

Intranodal palisaded myofibroblastoma originating from retroperitoneum: an unusual origin

BACKGROUND

Intranodal palisaded myofibroblastoma is one of the primary mesenchymal tumours. The inguinal region is the commonest site of this rare tumour. As there are only about 55 such cases reported in the literature, the precise aetiology and pathogenesis have yet to be explained adequately. Here we report a case of a 72 year old man presented with incidental finding of intranodal palisaded myofibroblastoma in the retroperitoneal region.

CASE PRESENTATION

A 72-year old man presented with abdominal pain in right upper quadrant with an incidental finding of abdominal mass in the right flank. The computerised tomogram scan of abdomen confirmed acute cholecystitis with a 5 x 5 cm retroperitoneal mass. He underwent cholecystectomy with excision of this mass. He recovered well following his operation and was discharged from the hospital. Histological examination confirmed the diagnosis of intranodal palisaded myofibroblastoma.

CONCLUSION

To our knowledge, this is the first case of intranodal palisaded myofibroblastoma originating from retroperitoneum. Along with the rarity of this case, we also discussed its typical histopathological findings, aetiology and pathogenesis.

Intranodal palisaded myofibroblastoma (intranodal hemorrhagic spindle cell tumor with amianthoid fibers): a case report and literature review

Intranodal palisaded myofibroblastoma (IPM) is a benign mesenchymal neoplasm originating from smooth muscle cells and myofibroblasts. It is characterized by spindle cells, amianthoid fibers, and by the proliferation of hemosiderin-containing histiocytes in the lymph node. A nodular lesion was excised from the inguinal region of an 80-year-old male patient. Macroscopic examination of a section of the lesion demonstrated a solid appearance with hemorrhagic areas. Microscopic examination revealed spindle cell proliferation, amianthoid fibers, hemosiderin pigment, and extravasated erythrocytes. Nuclei of the spindle cells displayed a palisaded appearance. Compressed lymphoid tissue was observed around the lesion. With Masson's trichrome, spindle cells stained as smooth muscle, whereas collagen staining was observed in homogeneous eosinophilic accumulations. Neoplastic cells were identified by the presence of vimentin and SMA. The Ki67 index was less than 1%. In light of these results, the case was diagnosed as "intranodal palisaded myofibroblastoma." IPM is an uncommon neoplasm originating from the stromal component of the lymph node. Although IPM is benign, it is frequently confused with metastatic lesions.

Intranodal palisaded myofibroblastoma: a case report

Intranodal palisaded myofibroblastoma is a rare benign soft tissue tumor, almost always arising from inguinal lymph nodes. It usually presents as a painless, slow-growing inguinal mass. We report herein a case of an intranodal palisaded myofibroblastoma occurring in a 36-year-old man. The salient clinicopathologic features of this unusual tumor are presented and the literature is briefly reviewed.

Intranodal palisaded myofibroblastoma; a case report and review of the literature

Intranodal palisaded myofibroblastoma (IPM) also called as intranodal hemorrhagic spindle cell tumor with amianthoid fibers is a distinctive and rare mesenchymal neoplasm of lymph nodes. This entity generally misdiagnosed as intranodal Kaposi's sarcoma or schwannoma in past. In contrast to Kaposi's sarcoma, it behaves in a benign fashion and does not need any further therapy except total surgical resection of the mass. This neoplasm has a great predilection for the inguinal region. The lesion presents typically as a unilateral, painless, solitary mass. To our knowledge, approximately 53 cases of IPM have been reported in the English-language literature. We present a 43-year-old-male patient with IPM and discuss histological, immunohistochemical features and pathogenesis of this rare benign neoplasm.

Intranodal palisaded myofibroblastoma

Intranodal palisaded myofibroblastoma (IPM) usually presents as a painless, slow-growing inguinal mass. Our review of 42 cases from 13 publications indicates that two thirds of IPMs occur between the ages of 45 and 55 years, the male-female ratio is 2:1, and there is a lack of ethnic predilection. Grossly, the IPM cut surface shows areas of hemorrhage. Five microscopic features are seen: (a) compressed remnants of lymphoid tissue at the periphery; (b) spindle cells with nuclear palisading; (c) intraparenchymal hemorrhage and erythrocyte extravasation; (d) so-called amianthoid fibers; and (e) intracellular and extracellular fuchsinophilic bodies that stain positive for smooth muscle actin. Immunohistochemically, IPM is positive for smooth muscle actin and cyclin D1 and negative for S100, glial fibrillary acidic protein, CD34, and desmin, and it shows a low proliferative index of Ki-67. Electron microscopy demonstrates features of myofibroblasts and smooth muscle cells. Excellent prognosis is seen after surgical treatment, with an approximately 6% recurrence rate and no malignant transformation.