Malignant glomus tumor arising in association with a fumarate hydratase-deficient leiomyoma: An unusual collision tumor

Collision tumors, defined as "two independent neoplasms that occur in close proximity to one another but maintain distinct boundaries," are quite rare. We report an exceptional collision tumor composed of a genetically confirmed malignant glomus tumor and a fumarate hydratase (FH)-deficient leiomyoma, presenting as a subcutaneous thigh mass in a 38-year-old male who was known to have hereditary leiomyomatosis and renal cell carcinoma syndrome. Microscopic examination identified a biphasic subcutaneous mass comprising sheets and nodules of glomus cells, with nuclear atypia and mitotic activity, and fascicles of mitotically inactive smooth muscle with variably pleomorphic nuclei and intracytoplasmic eosinophilic inclusions, features of FH-deficient leiomyoma. Immunohistochemistry demonstrated loss of FH and robust 2-succinocysteine expression in the smooth muscle, with a normal (FH-retained) expression pattern in the glomus tumor. Next-generation sequencing, performed on the glomus tumor component, identified CARMN::NOTCH2 fusion, characteristic of malignant glomus tumors. Awareness of the distinctive morphologic, immunohistochemical, and molecular genetic features of glomus tumors and FH-deficient leiomyomas is important for correct clinical management of patients with exceptional collision tumors of this type.

Infiltrative fibrous lesion of the facial nerve mimicking a facial nerve tumor

PURPOSE

To report three cases of facial nerve lesions that were clinically expected to be facial nerve tumors but showed fibrotic infiltration without any apparent signs of a specific tumor on histopathological findings. We also aimed to investigate the clinical characteristics of these cases.

METHODS

Medical records of patients who underwent surgery for facial nerve lesions were reviewed.

RESULTS

All three cases initially had House-Brackmann (HB) grade IV-V facial nerve palsy. On radiological imaging, schwannoma or glomus tumor originating from the facial nerve was suspected. All patients underwent complete surgical removal of the neoplasm followed by facial nerve reconstruction using the sural nerve. The lesions were histologically confirmed as infiltrative fibrous lesions without tumor cells. In two cases, facial nerve palsy improved to HB grade III by nine months post-surgery, and there were no signs of recurrence on follow-up MRI. The other case, after 1 year of follow-up, showed persistence of HB grade V facial nerve palsy without any evidence of recurrence.

CONCLUSION

Fibrotic lesions of the facial nerve could mimic primary facial nerve tumors. Clinicians should consider this condition even when a facial nerve tumor is suspected.

Lower extremity peripheral nerve pathology: Utility of preoperative ultrasound-guided needle localization before operative intervention

Historically, the use of ultrasound (US) in the management of peripheral nervous system (PNS) pathology has been limited to diagnostic confirmation or guidance for interventional injections. This technical case series will demonstrate the utility and versatility of preoperative US-guided needle localization for the excision of lower extremity neuromas and other pathology of the PNS. Five patients with symptomatic lower extremity PNS tumors were retrospectively reviewed. This case series corroborates the technical nuances of localizing lower extremity neuromas by US-guided needle and wire placement prior to operative excision. This was achieved by a multidisciplinary team that included plastic surgery, neurosurgery, and radiology. Five patients had US-guided needle localization of a lower extremity PNS target prior to operative intervention. Three patients had lower extremity neuromas of varying origins, including the lateral femoral cutaneous nerve (LFCN), saphenous nerve, and sural nerve. The remaining two patients had a sciatic nerve sheath Schwannoma and a femoral nerve glomus tumor. Under sonographic visualization, a needle was advanced to the target perimeter and withdrawn, leaving behind a percutaneous guidewire. This technique simplified the marking of the nerve course prior to dissection and led to efficient intraoperative identification of all five PNS tumors without any complications. Preoperative US-guided needle localization led to safe, accurate, and efficient perioperative and intraoperative identification of neuromas and other PNS tumors of the lower extremity prior to excision. By reducing the challenges of nerve identification in a scarred tissue bed, this multidisciplinary approach may decrease postoperative patient morbidity.

[Paraganglioma (glomus tumour) of the head and neck, a rare and demanding diagnosis]

Paragangliomas of the head and neck are rare tumours arising from extraadrenal ganglia. They are highly vascular lesions and are normally benign and not hormone secreting. Symptoms are usually discreet and the tumours often present as a lump in the neck or are diagnosed incidentally. Evaluation of paragangliomas of the head and neck, and surgery when indicated, is highly specialized care to be performed at two hospitals nationwide (in Region Uppsala and Region Skåne). Historically, treatment has mainly been surgical. However, with a multidisciplinary evaluation of each case recommendations can be individualized and treatment options may include surgery, radiotherapy or watchful waiting (wait-and-scan). When surgery is recommended for paragangliomas of the neck, it is best performed in collaboration between head-neck surgeons and vascular surgeons. Follow up in benign cases is mainly done through imaging.

Tumour-induced osteomalacia due to residual benign glomangioma

Tumour-induced osteomalacia (TIO) is a rare paraneoplastic syndrome. The constellation of findings of unprovoked fractures, hypophosphataemia, urinary phosphate wasting and a negative genetic evaluation suggest a TIO diagnosis. Tumours leading to TIO are often small and difficult to localise using standard imaging studies. The 68Ga-DOTATATE CT/positron emission tomography, a somatostatin receptor imaging modality, is the radiographical study of choice for localisation. It is highly sensitive and specific since tumours that cause oncogenic osteomalacia have been shown to express somatostatin receptors. Complete surgical resection is the treatment of choice; however, it may not always be feasible. Burosumab, a human anti-fibroblast growth factor-23 monoclonal antibody, is a therapeutic option in cases of unresectable TIO to normalise phosphorus levels and improve fracture healing. Our patient was initiated on burosumab, which led to healing of his fractures and profound symptomatic improvement of his pain. TIO is often undiagnosed for many years, leading to significant patient morbidity.

[Nail disorders in daily practice]

Familiarity with common nail disorders enables the clinician to diagnose and treat nail disorders and to recognize red-flag conditions. Knowledge of the anatomy of the nail unit is essential to understand the origin of nail disorders. This article focuses on neoplasms, abnormalities of nail color and shape, infections, and inflammatory conditions of the nail unit. There are various neoplasms of and around the nail unit, like squamous cell carcinoma (in situ), melanoma, and benign neoplasms such as mucous cyst, subungual exostosis, glomus tumor, onychopapilloma and fibro(kerato)ma. The most common deviating colors of the nail are red, white and brown-black. Abnormalities of nail color and shape may indicate an underlying systemic disease. Infections of the nail unit include onychomycosis, acute paronychia, pseudomonas nail infection and verruca vulgaris. The inflammatory conditions we discuss in this article are chronic paronychia, psoriasis, alopecia areata and lichen planus.

GLI1 Gene Alterations in Neoplasms of the Genitourinary and Gynecologic Tract

We report 4 neoplasms of the kidney (2 cases) and uterus (2 cases) harboring rearrangements or amplifications of the GLI1 gene, which because of their unusual clinical presentation, morphology, and immunoprofile mimicked other neoplasms, causing significant diagnostic challenge. The neoplasms occurred in 4 female patients ages 33 to 88 years. Histologically they all demonstrated nodular growth, solid architecture, bland epithelioid to ovoid-spindle cells with pale cytoplasm set in a variably myxoid or hyalinized stroma. One uterine tumor also demonstrated a focal round cell pattern, while another demonstrated focal pleomorphism. Unlike most previously reported neoplasms with these genetic abnormalities, the neoplasms in the current series were negative for S100 protein and minimally reactive for actin. All labeled for CD10 and cyclin D1, while 2 labeled for estrogen receptor and BCOR and 1 labeled for desmin, raising consideration of endometrial stromal sarcoma, myxoid leiomyosarcoma, metastatic breast carcinoma, and glomus tumor. One renal neoplasm demonstrated a GLI1-FOXO4 gene fusion and the other harbored a GLI1 gene rearrangement (unknown partner). The 2 uterine neoplasms exhibited GLI1 gene amplifications. GLI1-altered neoplasms (particularly those with GLI1 amplification) show variable morphology and lack a consistent immunophenotype, and thus may trigger diagnostic challenges which can be resolved by molecular testing.

[Changes in treatment paradigm for neurosurgical patients in the era of stereotactic irradiation. By the 15th anniversary of the Neuroradiosurgery in Russia]

INTRODUCTION

Stereotactic method and new irradiation techniques ensured radiosurgical treatment with high precision and conformity and significantly expanded the indications for stereotactic irradiation in neurosurgery.

MATERIAL AND METHODS

Over 15-year period, 29 976 patients underwent irradiation in various modes of fractionation on linear accelerators and Gamma Knife system at the first national radiosurgery center.

RESULTS

Stereotactic radiotherapy and radiosurgery are followed by minimal number of complications and side reactions. At the same time, 5-year control of tumor growth for skull base meningioma was 96.8%, neuroma - 97%, glomus tumor - 94%, pituitary adenoma - 96-98%, craniopharyngioma - 95% in overall 10-year survival 86%, pilocytic astrocytoma - 97.5% in overall 5-year survival 99%. In intracranial metastases, median overall survival after radiosurgery was 10.1 months, 24- and 36-month overall survival - 25.9% and 19.2%, respectively. In patients with recurrent high-grade glioma, overall survival was 27.4 months. In case of metastatic spine lesions, control of tumor growth within 1 year was achieved in 90% of patients, pain relief - in more than 50% of cases. Obliteration of AVM and dural fistula was found in more than 80% of patients in years after treatment. Reduction or disappearance of pain was also observed in 80% of patients with trigeminal neuralgia.

CONCLUSION

Stereotactic irradiation is effective and safe in patients with various pathologies of the central nervous system and characterized by high socio-economic indicators. Our own data indicate more significant role of stereotactic irradiation in the treatment of neurosurgical patients and make it possible to revise the existing treatment standards.

Considerazioni Sui Tumori Glomici Con Particolare Riguardo Alla Localizzazione Gastrica

The glomic tumours of the stomach are exceedingly unfrequent, occur in the middle age, have a slow or very slow evolution and are small in size. Histologically, they must be distinguished from the more frequent haemangiopericytomas. Clinically, they are characterized by gastralgiae of ulcerous and haemorrhagic type. A personal case, which adds to the 7 ones referred to in the literature, is exposed. It concerns a woman aged 45, who has been suffering for 4 months from anorexia, vomit and postprandial pain. She was operated upon 2 years ago, and at present she is well.

Glomus tumour of the deltoid muscle. A case report

Glomus tumours around the shoulder are very rare. To the best of our knowledge, seven cases have been reported to date. We present a case with special emphasis on its localization and time of appearance. Contrary to the related reports in the literature, the lesion was of short duration and it became symptomatic just 6 months before referral. Complete pain relief was achieved with surgical treatment.

Pediatric hand tumors. A review of 349 cases

Ganglion cysts, foreign bodies and vascular malformations are some of the most common causes of a palpable mass in the pediatric hand. There are other rarer tumors, such as digital fibromas, which are unique to the pediatric population. Malignant tumors are exceedingly rare. An awareness of both the common and unusual tumors seen in the pediatric population is essential for the hand surgeon evaluating these patients.

Vascular tumors in children

Tumors with a vascular component are the most common masses seen in children. Malformations and hemangiomas predominate. Hemangiomas have a biphasic natural history consisting of initial proliferation followed by spontaneous involution; these tumors rarely require surgical intervention. Malformations present at birth or shortly after birth and have a wide spectrum of clinical presentations depending upon their predominant cell type and rheology. Physical examination and MR imaging will effectively define most of these anomalies. Surgery is reserved for very symptomatic lesions and is effective in all but the fast-flow, Type C group of malformations. Glomus tumors, pyogenic granulomas and both traumatic and iatrogenic aneurysms are also seen in the pediatric age group. All are benign and effectively treated surgically. Malignant vascular tumors are rare in this age group.

Benign and malignant vascular tumors of the upper extremity

Vascular tumors of the upper extremity comprise a wide and varied group of pathologies. A variety of benign and malignant tumors exist. Proper diagnosis is imperative for the proper management of these lesions. On occasion, diagnosis can be made by a careful history and physical examination. However, the differentiation of benign from malignant tumors often requires permanent histologic section analysis by an experienced tumor specialist. The malignant vascular lesions, although rare, are aggressive in their behavior and require prompt diagnosis and treatment for patient survival.

[Glomus cell clusters of the lymph node]

Nine lymph nodes with so-called benign nevus cell nevi were studied by light microscopy. In three cases the lymph nodes were also examined by electron microscopy. The solitary or multiple cell clusters were 35-645 mu in diameter and were usually found in the lymph node capsule or cortex. They were more frequent in the older patients. There was no predisposition for either sex. Specific morphologic features allowing clear cytologic identification of the cells were not evidient. In particular, there was no indication that they represented nevus cells. However, they showed a great morphologic similarity to glomus cells. In addition, they were usually found near blood vessels. We assume that the cell clusters were hamartias related to glomangiomas. We call them glomus cell clusters.