Ectomesenchymal Chondromyxoid Tumor of the Anterior Tongue: A Case Image.

Ectomesenchymal chondromyxoid tumor (ECT) is a rare soft tissue tumor with peculiar histogenesis, exhibiting a predilection for the dorsum of the tongue. Molecular evidence suggests that it may originate from the migration of ectomesenchymal pluripotent cells from the neural crest to the tongue, where these cells may eventually proliferate and undergo myxoid and chondroid differentiation. This article illustrates a case of a 16-year-old female patient who presented with a nodule on the dorsum of her tongue, which had been present for four years. Surgical excision was performed, and histopathological analysis revealed a myxoid neoplasia composed of polygonal and spindle cells within a loose stroma containing chondroid areas. Tumor cells were positive for GFAP and S-100 proteins on immunohistochemical study, confirming the diagnosis of ECT. After a 5-year follow-up, the patient has shown no evidence of recurrence. Although rare, ECT can be diagnosed straightforwardly due to its distinctive clinical, histopathological, and immunohistochemical features. Clinicians and pathologists should become familiar with this tumor in order to avoid misdiagnosis.

Malignant Epithelioid Mesenchymal Neoplasm with FUS::CREM Gene Fusion Arising in the Tongue: A Case Report Detailing Clinicopathological, Imaging, and Molecular Features.

FUS::CREM fusion is a distinct primary driver in rare neoplasms of the head and neck and other anatomic sites. Herein, we describe the clinicopathological, imaging, and molecular features of a malignant epithelioid mesenchymal neoplasm harboring FUS::CREM fusion, arising in the tongue of a 46-year-old male. Clinically, the patient presented with a left upper neck mass. Imaging revealed a 4.0 cm mass at the left base of tongue. Histologically, the tumor consisted of sheets of loosely cohesive, small round to ovoid cells with moderate cytoplasm, small nuclei with coarse chromatin, frequent nuclear pseudoinclusions, and dense peripheral lymphoplasmacytic and histiocytic infiltrates. Malignant features, including tumor necrosis, perineural invasion, and increased mitotic activity were observed; however, lymphovascular invasion was absent with no evidence metastatic disease in the examined lymph nodes. A comprehensive panel of immunohistochemical stains showed positivity for synaptophysin and ALK, with negative results for all other markers. RNA-based next-generation sequencing using anchored multiplex polymerase chain reaction (PCR) was performed and detected FUS::CREM fusion gene. The patient was treated by excision and postsurgical chemoradiation with no evidence of recurrence after four months. Additional cases supported by comprehensive clinical data collected over an extended period are necessary to precisely characterize epithelioid mesenchymal neoplasms harboring FUS::CREM fusion in the head and neck.

Fibrocartilaginous Mesenchymoma of the Spine: A Case Report.

CASE: A healthy, 19-year-old woman was incidentally found to have a large, destructive tumor of T11 without neurologic symptoms. Biopsy demonstrated fibrocartilaginous mesenchymoma (FCM). The patient was treated with resection including subtotal corpectomy and T8-L1 fusion with use of cage and allograft strut construct. The patient remained without recurrence over 3 years of follow-up. CONCLUSION: FCM arising from the spine is a rare tumor, of which this is the sixth report. FCM affects primarily young adults and is benign but locally aggressive, requiring complete excision to prevent recurrence.

Multimodality Imaging of Intimal Sarcoma Causing Both Severe Mitral Stenosis and Mitral Regurgitation.

Intimal sarcomas (IS) are rare, malignant, rapidly progressive mesenchymal tumors that typically occur in the tunica intima of larger vessels, and they rarely involve the heart. IS are frequently misdiagnosed during the initial clinical presentation. This case report describes an uncommonly located IS, highlighting specific findings obtained through multimodality imaging.

Intracranial Phosphaturic Mesenchymal Tumors: A Systematic Literature Review of a Rare Entity.

BACKGROUND: Phosphaturic Mesenchymal Tumors (PMTs) are rare mesenchymal neoplasms known for producing Tumor-induced Osteomalacia (TIO). TIO is an uncommon paraneoplastic syndrome characterized by radiographic evidence of inadequate bone mineralization and analytical abnormalites. METHODS: We sought to present a case of TIO caused by skull base PMT with intracranial extension, manifesting with pain, progressive weakness, and multiple bone fractures. Furthermore, a systematic review was performed, following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. A search was conducted in PubMed database with title/abstract keywords "Phosphaturic mesenchymal tumor" and "Osteomalacia." Search results were reviewed looking for intracranial or skull base tumors. RESULTS: Our systematic review included 29 reported cases of intracranial PMT. In the reviewed cases there was a significative female predominance with 22 cases (75,86%). Osteomalacia was presented in 25 cases (86,20%). Bone fractures were present in 10 cases (34,48%). The most common site of involvement was the anterior cranial fossa in 14 cases (48,27%). Surgery was performed in 27 cases (93,10%) with previous tumor embolization in 4 cases (13,79%). Total recovery of the presenting symptoms in the first year was achieved in 21 cases (72,41%). Recurrence of the disease was described in 6 cases (25%). CONCLUSIONS: Skull base PMTs with intracranial extension are extremely rare tumors. Most patients are middle-aged adults with a PMT predominantly located in anterior cranial fossa. Surgery is the current treatment of choice with optimal outcome at 1-year follow-up, although recurrence could be present in almost 25% of the cases.

A 50-Year-Old Man Presenting with Multiple Bone Lesions and a Diagnosis of Phosphaturic Mesenchymal Tumor of the Femur.

BACKGROUND Phosphaturic mesenchymal tumor (PMT) is an extremely rare mesenchymal neoplasm that is commonly seen in bone and soft tissue. It is associated with a paraneoplastic syndrome, oncogenic osteomalacia, due to tumor-induced urinary phosphate wasting. It is demonstrated to be predominantly mediated by fibroblast growth factor 23 (FGF23)/fibroblast growth factor receptor 1 (FGFR1) axis. Clinically, PMT usually presents as a solitary lesion in the bone. The diagnosis of PMT is challenging due to its non-specific clinical manifestation, radiologic findings, and morphological features. CASE REPORT We report the case of a 50-year-old man presenting with multiple lytic bone lesions and associated pathologic fracture of the right femur, clinically suspicious for multiple myeloma or other metastatic malignant process. Resection from the right femur showed a hypercellular lesion composed of oval-to-spindled cells infiltrating the native trabecular bone with admixed multinucleated giant cells. Immunohistochemical (IHC) staining and in situ hybridization (ISH) demonstrated the tumor cells were positive for SATB2, ERG, FGFR1, and FGF23 ISH. DNA and RNA next-generation sequencing showed marked increases in mRNA levels of FGF23 and FGFR1. The constellation of clinicoradiologic, histomorphologic, IHC, and molecular findings supported a diagnosis of primary benign PMT. CONCLUSIONS This case report discusses a patient with PMT presenting with multifocal lesions due to tumor-induced osteomalacia at initial presentation. We hope that this report will increase the awareness of clinician and pathologists of PMT as a differential diagnosis in patients presenting with multifocal lytic bone lesions. In turn, this will prevent misdiagnosis and overtreatment of a typically benign process.

Phosphaturic mesenchymal tumor: management and outcomes of ten patients treated at a single institution.

BACKGROUND: Phosphaturic mesenchymal tumor (PMT) is a rare tumor that causes tumor-induced osteomalacia. Patients present with non-specific symptoms secondary to renal phosphate wasting and decreased bone mineralization. We sought to assess: (1) What are the common presenting features, laboratory and imaging findings, histologic findings of phosphaturic mesenchymal tumors? (2) What are the available treatment strategies for phosphaturic mesenchymal tumors and their long-term outcomes in terms of local recurrence and symptom control after treatment? METHODS: We retrospectively identified patients with a histologic diagnosis of PMT located in the axial or appendicular skeleton, or surrounding soft tissues. A total of 10 patients were finally included in our study. RESULTS: Median tumor size was 1.9 cm (range, 1.1 to 6.1) and median time from symptom onset to diagnosis was 3 years (range, 0.5 to 15 years). All patients but one presented with hypophosphatemia (median 1.9 mg/dL, range 1.2 to 3.2). Pre-operative FGF-23 was elevated in all cases (median 423.5 RU/mL, range 235 to 8950). Six patients underwent surgical resection, three were treated percutaneously (radiofrequency ablation or cryoablation), and one refused treatment. Only one patient developed local recurrence and no patients developed metastatic disease. At last follow-up, nine patients showed no evidence of disease and one was alive with disease. CONCLUSION: Phosphaturic mesenchymal tumor is a rare tumor presenting with non-specific symptoms. Surgery is the standard treatment when negative margins can be achieved without significant morbidity. In patients with small tumors in surgically-inaccessible areas, radiofrequency ablation or cryoablation can be performed successfully.

Phosphaturic mesenchymal tumor: Clinicopathological features with outcomes in 10 patients with review of literature.

BACKGROUND: Phosphaturic mesenchymal tumors (PMTs) are rare mesenchymal tumors, associated with long-standing, non-specific but often debilitating symptoms in the affected patients. These tumors display characteristic histopathological features and in case, identified timely, can be a boon for patients, given an excision is completely curative. AIMS: To evaluate the clinical and histopathological features of 10 PMTs, diagnosed at our institution, along with clinical outcomes in those patients. MATERIALS AND METHODS: This was a retrospective study, wherein 10 PMTs, diagnosed from January 2013 to July 2022, were included. RESULTS: The average age at the time of diagnosis was 40 years with an M:F ratio of 4:1. Clinical features included lumps, weakness, bone pain, difficulty in moving and walking, and pathologic fractures. The biochemical analysis showed normal serum calcium levels (average = 9.5 mg/dL), with low serum phosphorus (average = 2.2 mg/dL) and raised serum fibroblast growth factor 23 (FGF23) levels, in all the cases, wherever available. On histopathology, all tumors showed cells arranged in a hemangiopericytomatous pattern, including oval to short spindle forms. Multinucleate giant cells were present in nine tumors, and characteristic "grungy calcifications" was observed in eight tumors. Prominent pseudo cystic spaces were seen in eight tumors. A significant number of mitotic figures and tumor necrosis were not seen in any tumor. In five cases where follow-up was available, there was complete resolution of symptoms post-resection with no recurrence or metastasis. All those patients were free of disease until the last follow-up. CONCLUSION: This constitutes the first largest comprehensive study on these rare tumors from our country. PMTs can be diagnosed based on certain histopathological features and correlation with clinicoradiological and biochemical findings. These are invariably benign neoplasms. Patients are relieved of their debilitating symptoms after adequate surgical tumor resection. Therefore, their correct and timely diagnosis is crucial.

Intracranial Phosphaturic Mesenchymal Tumor Detected by 68 Ga-DOTATATE PET/CT.

ABSTRACT: A 68 Ga-DOTATATE PET/CT scan was conducted to locate the causative tumor responsible for suspected tumor-induced osteomalacia in a 56-year-old woman. The PET/CT images showed a focus in the right occipital region. Subsequent MRI showed an extra-axial nodule in the right occipital region, mimicking a meningioma. Although rare, an intracranial phosphaturic mesenchymal tumor was still suspected because of the typical clinical settings. Finally, phosphaturic mesenchymal tumor was confirmed by the postoperative pathology.

Treatment and Diagnose of Spinal Phosphaturic Mesenchymal Tumor: A Case Report and a Systematic Literature Review.

BACKGROUND: Spinal phosphaturic mesenchymal tumor (PMT) is a rare disorder but can be cured once the diagnosis is clear and a complete removal by surgery is performed. To the best of our knowledge, only 22 cases in the spine have been described, and we report a case with the largest number of spinal segments (T12-L5) affected among spine PMT cases. METHODS: A comprehensive literature search was performed until May 23, 2023, following the Preferred Reporting Items for Systematic Reviews guidelines. Studies were chosen through relevant PubMed, Web of Science, and EMBASE searches to prioritize obtaining the largest studies. The Medical Subject Headings and Boolean operators employed for this search were ("PMT" or "TIO" or "Tumor-induced osteomalacia" or "phosphaturic mesenchymal tumor") and ("spine" or "spinal"). Two researchers (L.S.Z. and D.B.C) independently reviewed and evaluated the included articles. Any differing opinions were discussed until a consensus was reached. A total of 18 studies were included. A case report is also presented. RESULTS: We report a case of spinal PMT. The full text of the relevant articles was construed. A total of 18 studies were reviewed and consolidated. These articles are roughly divided into the following 5 subcategories: 1) clinical features and baseline distribution, 2) laboratory and imaging findings, 3) pathological manifestations, and 4) surgical methods and treatment options. CONCLUSIONS: Spinal PMT is very rare with a high rate of misdiagnosis and debilitating complications, so it is of significance to increase awareness of the disease among spine surgeons consulted by patients with spinal PMT. 68Ga-DOTATOC-PET/CT shows very high sensitivity to the spinal PMT but there is no way to exactly determine the location of the tumor. PMT has unique immunohistochemical characteristics and malignant PMT is rare. Once diagnosed, complete surgical excision is the recommended treatment. Burosumab is one of the available options, especially in cases that are recurrent and difficult to surgically resect.

A Phosphaturic Mesenchymal Tumor Presenting as Reversible Metabolic Myopathy.

Tumor-induced osteomalacia (TIO) is a disorder in which the clinical signs and symptoms of osteomalacia and the biochemical abnormalities of hypophosphatemia, phosphaturia, and low serum levels of 1,25(OH)2 Vitamin D3 are secondary to a neoplasm. A 33-year-old woman presented with musculoskeletal pain and proximal myopathy with a duration of 2.5 years which was treated with Vitamin D supplements. On the basis of the biochemical tests and histopathology, she was reevaluated and found to have TIO secondary to a phosphaturic mesenchymal tumor. The tumor was resected (limb salvage with endoprosthesis), and she had no pain or weakness at followup. The case reminds the readers to consider the possibility of TIO when evaluating patients with isolated hypophosphatemia, which may lead to long-term disability and prolonged morbidity if untreated. Early recognition and diagnosis of TIO is crucial since resection of the tumor usually reverses its manifestations.

Tumor mesenquimático fosfatúrico de pelvis: abordaje multidisciplinario / Phosphaturic mesenchymal tumor of the pelvis: A multidisciplinary approach

El tumor mesenquimático fosfatúrico es una entidad clinicopatológica sumamente infrecuente. Además de provocar dolor óseo insidioso y polimialgias, se acompaña de alteraciones del metabolismo fosfocálcico de difícil manejo clínico. El abordaje multidisciplinario resulta la clave del éxito en esta enfermedad. Presentamos una paciente de 52 años de edad con antecedente de tumor mesenquimático fosfatúrico en la hemipelvis derecha con extensión a la cadera homolateral de 10 años de evolución. Clínicamente presentaba osteomalacia oncogénica (hipofosfatemia e hiperfosfaturia) que no se corregía, pese a un agente de última generación, el burosumab, un inhibidor del factor de crecimiento fibroblástico 23, que aumenta la reabsorción tubular renal de fosfatos. En un comité multidisciplinario, se decidió la resección con márgenes oncológicos y se logró una mejoría clínica franca. Comunicamos este caso, debido a que es un cuadro infrecuente. Nivel de Evidencia: IV

Phosphaturic mesenchymal tumor (PMT) is an infrequent clinicopathological entity. It presents insidious bone pain and polymyalgia, accompanied by alterations in calcium and phosphorus metabolism that are difficult to resolve clinically. A multidisciplinary approach is a key to success in this pathology. We present the case of a 52-year-old female patient with a 10-year history of PMT in the right hemipelvis with ipsilateral hip extension. From the clinical point of view, she presented oncogenic osteomalacia (hypophosphatemia and hyperphosphaturia) that did not correct despite being administered the latest generation medication, burosumab, an FGF-23 inhibitor that increases renal tubular phosphate reabsorption. Resection with oncological margins was decided by a multidisciplinary committee resolving her clinical condition. Due to the rarity of this pathology, we decided to report the case. Level of Evidence: IV

Angiomixoma agresivo postrasplante renal / Aggresive angiomyxoma after renal transplantation

La condición de inmunosuprimido aumenta el riesgo de cáncer en trasplantados renales, en comparación a la población general. La mejor supervivencia de esta población en los últimos años ha convertido a las neoplasias y a la enfermedad cardiovascular en las principales causas de morbi-mortalidad. Presentamos el caso de un paciente trasplantado renal que desarrolló cuatro años después del trasplante una forma inusual de tumor mesenquimatoso, el angiomixoma agresivo, que requirió resección quirúrgica amplia.

The condition of immunosuppressed increases the risk of cancer in kidney transplant patients, as compared to the general population. The best survival of inmunosupressed patients in recent years has turned both neoplasms and cardiovascular diseases into the main causes of morbidity and mortality. We present the case of a renal transplanted patient who developed an unusual form of mesenchymal tumor such as the aggressive angiomyxoma, four years after the implant and requiring wide surgical resection.

Endoscopic Ultrasonography in the Diagnosis and Treatment Strategy Choice of Esophageal Leiomyoma

OBJECTIVES: Esophageal leiomyoma is the most common benign tumor of the esophagus, and it originates from mesenchymal tissue. This study analyzed the clinicopathological characteristics of esophageal leiomyoma and aimed to evaluate the role of endoscopic ultrasonography in the diagnosis and treatment selection for these lesions. METHODS: Two hundred and twenty-five patients who had suspected esophageal leiomyomas in endoscopic ultrasonography were enrolled at the Endoscopy Center of The First Affiliated Hospital, Zhejiang University from January 1st, 2009 to May 31th, 2015. The main outcomes included the demographic and morphological characteristics, symptoms, comparisons of diagnosis and treatment methods, adverse events, and prognosis. RESULTS: One hundred and sixty-seven patients were diagnosed as having an esophageal leiomyoma by pathological examination. The mean patient age was 50.57±9.983 years. In total, 62.9% of the lesions originated from the muscularis mucosa, and the others originated from the muscularis propria. The median distance to the incisors was 30±12 cm. The median diameter was 0.72±0.99 cm. As determined by endoscopic ultrasonography, most existing leiomyomas were homogeneous, endophytic, and spherical. The leiomyomas from the muscularis mucosa were smaller than those from the muscularis propria and much closer to the incisors (p<0.05). SMA (smooth muscle antibody) (97.2%) and desmin (94.5%) were positive in the majority of patients. In terms of treatments, patients preferred endoscopic therapies, which led to less adverse events (e.g., intraoperative bleeding, local infection, pleural effusion) than surgical operations (p<0.05). The superficial leiomyomas presented less adverse events and better recovery (p<0.05) than deep leiomyomas. CONCLUSION: Endoscopic ultrasonography has demonstrated high accuracy in the diagnosis of esophageal leiomyomas and provides great support in selecting treatments; however, EUS cannot completely avoid misdiagnosis, so combining it with other examinations may be a good strategy to solve this problem.

Primary osteosarcoma of the breast: pathological and imaging findings / Osteossarcoma primário da mama: achados patológicos e de imagem

SUMMARY Primary osteosarcoma of the breast (POB) is an extremely rare and aggressive tumor. Differential diagnosis of POB includes osteosarcoma of the chest wall and metaplastic breast carcinoma. Imaging tests that exclude the existence of a direct connection between the tumor and chest wall, as well as histopathological and immunohistochemical studies that rule out the presence of an epithelial component are required for the diagnosis of POB. We report a case of a 69-year old woman with POB. Imaging and pathological findings are presented. Therapeutic approach is discussed in the light of current knowledge, including potential complications.

RESUMO O osteossarcoma primário da mama (OPM) é um tumor extremamente raro e agressivo. O diagnóstico diferencial do OPM inclui o osteossarcoma da parede torácica e o carcinoma metaplásico da mama. Exames de imagem que excluam a existência de uma conexão direta entre o tumor e a parede torácica, e estudos histopatológico e imuno-histoquímico que descartem a presença de um componente epitelial são necessários para o diagnóstico de OPM. Relatamos um caso de OPM em uma mulher de 69 anos de idade. Os achados de imagem e patológicos são apresentados. A abordagem terapêutica é discutida à luz do conhecimento atual, incluindo potenciais complicações.

Mesenquimoma fibrocartilaginoso de húmero proximal: reporte de un caso / Fibrocartilaginous mesenchymoma of the proximal humerus: case report

El mesenquimoma fibrocartilaginoso (MFC) es un tumor raro, que afecta principalmente a los huesos largos. Se han reportado pocos casos desde su descripción. Presentamos un caso de un niño de 4 años de edad con MFC situado en el húmero. Las radiografías mostraron una lesión lítica expansiva situada en la región metafisaria del húmero proximal. La resonancia magnética objetivó expansión del tumor a partes blandas. La anatomía patológica fue confirmatoria de MFC. El paciente fue tratado con curetaje, fenolización adyuvante y sustituto óseo mezclado con aspirado de médula ósea. A los dos años de seguimiento, no se evidenció recidiva. El MFC debe ser tenido en cuenta entre los diagnósticos diferenciales en lesiones óseas líticas en niños y adolescentes.

Fibrocartilaginous mesenchymoma (FCM) is a rare tumor that primarily affects the long bones. Few cases have been reported since its description. A case of a 4-year-old boy with FCM located in the humerus is presented. Radiological examination showed an expansive lytic lesion located in the metaphyseal proximal humerus. Magnetic resonance imaging showed soft tissue expansion. Histopathological diagnosis was confirmatory of FCM. Curettage, adjuvant phenolization, and bone grafting with bone substitute, and autologous bone marrow was performed. During a follow-up period of 2 years, there was no evidence of disease progression. FCM should be considered in the differential diagnosis of lytic bone lesions in children and adolescents.

Tumor mesenquimatoso fosfatúrico de fosa nasal con compromiso intracraneano: reporte de un caso y revisión de la literatura / Nasal fossa phosphaturic mesenchymal tumor with intracraneal compromise: case report and review of the literature

El tumor mesenquimatoso fosfatúrico (TMF) es una enfermedad extremadamente rara. Según evidencia reciente es causado por la sobreexpresión del factor de crecimiento fibroblástico 23 (FGF23), el cual genera hipofosfemia y osteomalacia. A continuación presentamos el caso de un paciente de 42 años con un tumor mesenquimatoso fosfatúrico de fosa nasal izquierda con extenso compromiso intracraneano. Cabe destacar que hasta la fecha hay 142 casos reportados de TMF en la literatura de los cuales solo 11 se ubican en fosa nasaly cavidades sinusales, y sólo dos de ellos ubicados en fosa nasal¹. El paciente tuvo una exitosa resolución quirúrgica con la consecuente normalización de parámetros analíticos (incluido el FGF23), mejoría sintomática y ausenia de recidiva hasta la fecha.

The phosphaturic mesenchymal tumor (PMT) is an extremely rare disease. According to recent evidence is caused by overexpression of fibroblast growth factor 23 (FGF23) which generates hypophosphatemia and osteomalacia. We report the case of a 42 year old patient with a left nasal fossa phosphaturic mesenchymal tumor with intracranial involvement. Should be noted that to date there are 142 reported cases of PMT in the literature of which only 11 are located in nasal fossa and sinus cavities, two of them located in nasal fossa¹. The patient had a successful surgical resolution with consequent normalization of analytical parameters (including FGF23), absence of symptoms and no recurrence to date.

Osteomalacia por tumor secretor de FGF-23 / Ostemalacia due to a tumor secreting FGF-23

Se presenta un caso de osteomalacia oncogénica en un varón de 50 años, con fuertes dolores óseos y gran debilidad muscular durante 4 años. Tenía varias deformidades vertebrales dorsales en cuña, fracturas en ambas ramas iliopubianas y en una rama isquiopubiana, y una zona de Looser en la meseta tibial derecha. Se localizó un tumor de 2 cm de diámetro en el hueco poplíteo derecho mediante centellograma con octreótido marcado con tecnecio. El tumor fue extirpado quirúrgicamente. La microscopía mostró un tumor mesenquimático fosfatúrico, de tejido conectivo mixto. La inmunotinción demostró FGF-23. Hubo rápida mejoría, con consolidación de las fracturas pelvianas y de la pseudofractura tibial y normalización de las alteraciones bioquímicas.

A case of oncogenic osteomalacia in a 50-year-old male is here presented. He suffered severe bone pain and marked muscular weakness of 4 years' duration. There were several vertebral deformities in the thoracic spine, bilateral fractures of the iliopubic branches, another fracture in the left ischiopubic branch, and a Looser's zone in the right proximal tibia. An octreotide-Tc scan allowed to identify a small tumor in the posterior aspect of the right knee. It was surgically removed. Microscopically, it was a phosphaturic mesenchymal tumor-mixed connective tissue (PMT-MCT). Expression of FGF-23 was documented by immune-peroxidase staining. There was rapid improvement, with consolidation of the pelvic fractures and the tibial pseudo-fracture. The laboratory values returned to normal.