Intervertebral disc degeneration in warmblood horses: Histological and biochemical characterization

Gross morphology of healthy and degenerated intervertebral discs (IVDs) is largely similar in horses as in dogs and humans. For further comparison, the biochemical composition and the histological and biochemical changes with age and degeneration were analyzed in 41 warmblood horses. From 33 horses, 139 discs and 2 fetal vertebral columns were evaluated and scored histologically. From 13 horses, 73 IVDs were assessed for hydration, DNA, glycosaminoglycans, total collagen, hydroxyl-lysyl-pyridinoline, hydroxylysine, and advanced glycation end-product (AGE) content. From 7 horses, 20 discs were assessed for aggrecan, fibronectin, and collagen type 1 and 2 content. Histologically, tearing of the nucleus pulposus (NP) and cervical annulus fibrosus (AF), and total histological score (tearing and vascular proliferation of the AF, and chondroid metaplasia, chondrocyte-like cell proliferation, presence of notochordal cells, matrix staining, and tearing of the NP) correlated with gross degeneration. Notochordal cells were not seen in IVDs of horses. Age and gross degeneration were positively correlated with AGEs and a fibrotic phenotype, explaining gross degenerative changes. In contrast to dogs and humans, there was no consistent difference in glycosaminoglycan content and hydration between AF and NP, nor decrease of these variables with age or degeneration. Hydroxylysine decrease and collagen 1 and AGEs increase were most prominent in the NP, suggesting degeneration started in the AP. In caudal cervical NPs, AGE deposition was significantly increased in grossly normal IVDs and total collagen significantly increased with age, suggesting increased biomechanical stress and likelihood for spinal disease in this part of the vertebral column.

Uterine Myxoid Leiomyosarcoma with Stromal Chondroid Metaplasia: A Rare Case Report

Background: Uterine leiomyosarcoma is a rare gynecological disease. Myxoid leiomyosarcoma (mLMS) is an aggressive and very uncommon type of leiomyosarcoma, with few cases reported in English literature. Stromal metaplasia is rare in leiomyosarcoma. Here we present huge uterine myxoid leiomyosarcoma with stromal chondroid metaplasia. Case Presentation: A 48–year–old single woman with lower abdominal pain and increased abdominal circumference. The detected mass on imaging was diagnosed as uterine mLMS with stromal chondroid metaplasia in the histopathological examination after surgery. Conclusion: Myxoid leiomyosarcoma should be considered in uterine mass with extensive myxoid change, infiltrative border, low mitotic count, and mild atypia. Stromal chondroid metaplasia can be seen in the myxoid leiomyosarcoma. [GMJ.2021;10:e1817]

Metaplastic carcinoma of the breast and BRCA1 germline mutation: a case report and review

Background Metaplastic carcinoma of the breast consists of both invasive ductal carcinoma and metaplastic carcinoma. This rare subtype of cancer has a poor prognosis. The development of metaplastic breast cancer and relationship with BRCA1 are not well known. Here, we report a rare case of germline BRCA1 mutation-positive breast cancer with chondroid metaplasia. Case presentation A 39-year-old Japanese woman with a family history of breast cancer in her mother and ovarian cancer in her maternal grandmother consulted at our hospital with a left breast mass. Needle biopsy for the mass was performed, leading to a diagnosis of invasive breast cancer with chondroid metaplasia. We performed left mastectomy + sentinel lymph node biopsy + tissue expander insertion and replaced with a silicone implant later. Pathological examination revealed that the patient had triple-negative breast cancer. Four courses of doxorubicin+ cyclophosphamide therapy were performed as adjuvant therapy after surgery. We performed genetic counseling and genetic testing, and the results suggested the germline BRCA1 mutation 307 T> A (L63*). She has currently lived without a relapse for 2 years post-surgery. Conclusions There have been only 6 cases of metaplastic breast carcinoma with germline BRCA1 mutations including our case. Patients with BRCA1 mutations may develop basal-like subtypes or M type of triple-negative breast cancer besides metaplastic breast cancers.

Morphological Changes in the Ligamentum Flavum in Degenerative Lumbar Canal Stenosis: A Prospective, Comparative Study

Study Design: Prospective, comparative.Purpose: To compare the histopathological and electron microscopic changes in the ligamentum flavum (LF) between degenerative lumbar canal stenosis (LCS) and lumbar disk herniation (LDH).Overview of Literature: The LF has been implicated as a key structure in the pathogenesis of LCS. With aging, the LF undergoes morphological changes–a decrease in the elastic component and an increase in the collagen component, in addition to other focal changes. By comparing the histopathological and electron microscopic picture of the LF in elderly patients with LCS with that in young patients with LDH, the role of this ligament in the pathogenesis of LCS may be clarified.Methods: Forty patients were prospectively recruited and divided into two groups: group 1 included 20 patients with degenerative LCS aged >55 years and group 2 included patients with LDH aged <35 years. The ligament flava were collected during the patients’ surgery. The features noted on histopathological examination included the fibrosis score, the loss of elastic fibers, calcification, chondroid metaplasia, mucinous degeneration, vascularization, long septa, clefts, granulation tissue, and ganglion-like cysts. The features noted on electron microscopic examination included the elastic fiber thickness, the quality of elastic fibers, the elastic:collagen ratio, calcification, melanin fibers, remnants of necrotic cells, and electron-dense material in the LF. All parameters were compared between group 1 and group 2.Results: On histopathological examination, the two groups exhibited significant differences regarding three parameters: chondroid metaplasia, long septa, and ganglion-like cysts. On electron microscopy examination, significant differences were observed between the two groups regarding two parameters: the quality of elastic fibers and the elastic:collagen ratio.Conclusions: Characteristic morphological changes may be noted on histopathological and electron microscopic examination that mark the degenerative changes in the LF that contribute to the occurrence and pathogenesis of degenerative LCS.

Chondro-Osseous Metaplasia in Ependymoma: A Rare Histopathological Finding

Ependymoma is a circumscribed glioma composed of uniform glial cells with bland nuclei in a fibrillary matrix. It is characterized by the presence of perivascular pseudorosettes. Unusual histopathological findings have rarely been reported in ependymomas, 0.5% of all diagnosed cases. Such unusual and exceedingly rare histological findings include osseous or chondroid metaplasia. To the best of our knowledge, only 15 cases of osseocartilaginous ependymomas have been reported in English literature. We report a 3-year-old boy who presented with ataxia, vomiting, and headache for three months. Radiological imaging revealed a posterior fossa lesion. Histopathological examination of the lesion confirmed a posterior fossa ependymoma with chondro-osseous metaplasia. The present case outlines the clinical presentation, histopathological findings, and outcome of chondro-osseous metaplasia in ependymomas. To date, the etiology of chondro-osseous metaplasia in ependymomas remains uncertain. Further research exploring such phenomenon is of paramount importance to explain how these tumors develop.

Metaplastic breast carcinoma with chondrosarcomatous differentiation: an unusual disease with a worse prognosis

Metaplastic breast carcinoma (MBC) has an incidence of <1% of all breast cancers and MBC with chondrosarcomatous differentiation is even more rare, <0.1% of all cases. The World Health Organization have classified MBC into pure epithelial-type and mixed epithelial and mesenchymal type. The epithelial-type MBC is sub-classified into squamous cell carcinoma, adenosquamous carcinoma and adenocarcinoma with spindle cell differentiation; mixed type MBC is sub-classified into carcinosarcoma and carcinoma with osseous and chondroid metaplasia. Metaplastic carcinomas of the breast are characterized by large tumour size and rapid growth, and they are usually estrogen receptor, progesterone receptor, and HER2/neu negative and tend to have a worse prognosis than other triple negative breast cancers. There is a noteworthy increased risk of tumour recurrence and a worse prognosis with MBC compared with invasive lobular carcinoma and infiltrating duct carcinoma. We report a case of metaplastic carcinoma with extensive chondroid differentiation that is chondrosarcoma and chondroid metaplasia along with classic infiltrating duct carcinoma with involvement of ipsilateral axillary lymph nodes.