Myoepithelial carcinoma of the parotid gland with a novel CTCF::NCOA2 fusion.

We describe a case of a myoepithelial carcinoma of the superficial parotid gland in a 46-year-old male harboring a novel CTCF::NCOA2 gene fusion. To our knowledge, this novel gene fusion has not been described previously in myoepithelial carcinoma. A 46-year-old male patient presented with a mass involving the superficial left parotid gland with extension into the external auditory canal (EAC) and erosion of the conchal cartilage. Histologically, the neoplasm was composed of uniform spindled, epithelioid/ovoid cells arranged in cords and nests within hyalinized to myxoid stroma. On immunohistochemistry (IHC), the tumor cells demonstrated patchy and variable staining for low molecular weight cytokeratin (CAM5.2), pan-cytokeratin (OSCAR), and S-100. Overall, the morphological and immunohistochemical attributes supported a locally aggressive tumor of myoepithelial differentiation consistent with myoepithelial carcinoma. Molecular analysis using a custom 115-gene gene panel by targeted RNA sequencing, showed an in-frame CTCF::NCOA2 fusion. In addition to reporting this novel fusion in myoepithelial carcinoma, we also discuss relevant differential diagnosis, and provide a brief review of NCOA2 gene function in both normal and neoplastic contexts.

Primary thyroid hemangioma, a rare diagnosis in a patient with a painless neck mass.

The aim of this case report is to demonstrate a case of primary thyroid hemangioma in a 62-year-old female who presented with a painless neck mass, treated with right hemithyroidectomy and diagnosed by surgical biopsy. Thyroid hemangiomas are rare, benign lesions which present a diagnostic challenge given the lack of specific imaging findings and clinical manifestations associated with them. However, accurate recognition of these lesions is important and can facilitate conservative, rather than surgical, management strategies. In this report, we discuss a case in a patient whose laboratory assessment raised concern for a thyroid paraganglioma, leading to surgical resection of what was ultimately a benign thyroid hemangioma. We also review the pathophysiology, clinical manifestations, differential diagnostic considerations, and imaging characteristics of thyroid hemangiomas across multiple modalities and discuss strategies for accurately diagnosing these lesions.

Droplet Digital PCR (ddPCR) as a Novel Technology in Detecting CTNNB1 Mutations in Desmoid Fibromatosis.

Desmoid fibromatosis (DF) is a locally aggressive soft tissue neoplasm with frequent recurrences. DF is characterized by alterations in the Wnt/ß-catenin pathway, with the majority showing sporadic mutations in CTNNB1 , whereas others have germline mutations in APC . Immunohistochemical staining for ß-catenin is often difficult to interpret and can be negative in up to 30% of cases. Prior studies have shown that some DFs lacking nuclear expression of ß-catenin may carry activating CTNNB1 mutations. Droplet digital polymerase chain reaction (ddPCR) has been used effectively in detecting mutations in formalin-fixed, paraffin-embedded (FFPE) samples of various cancer types. In this study, we assess the diagnostic utility of ddPCR to detect CTNNB1 mutations in DF with ß-catenin expression on immunohistochemistry (IHC), as well as in diagnostically challenging cases. Of the 28 DFs with nuclear ß-catenin expression by IHC, 24 cases showed a CTNNB1 mutation by ddPCR using primers against the most common point mutations in CTNNB1 . The most frequent mutation was T41A (n=14; 50%), followed by S45F (n=8; 33%) and S45P (n=3;12%). We identified 8 additional (myo)fibroblastic lesions of uncertain classification, which were negative for nuclear ß-catenin expression by IHC. We detected CTNNB1 mutations in 3 unknown lesions, including S45F (n=2) and S45P (n=1). ddPCR is a sensitive, rapid and cost-efficient methodology to detect common CTNNB1 mutations in DF, especially in diagnostically challenging cases.

Fédération Nationale Des Centres de Lutte Contre Le Cancer (FNCLCC) Grading, Margin Status and Tumor Location Associate With Survival Outcomes in Malignant Peripheral Nerve Sheath Tumors.

BACKGROUND: Histologic grading using the Fédération Nationale des Centres de Lutte Contre Le Cancer (FNCLCC) system is not universally accepted as applicable to malignant peripheral nerve sheath tumor (MPNST), as its prognostic value is not well established. METHODS: We retrospectively evaluated 99 cases of MPNST to investigate any association between the outcomes overall survival (OS) and progression-free survival (PFS), and predictor variables FNCLCC grade, clinical setting, tumor location, and tumor size at diagnosis using multivariable Cox proportional hazard analysis. RESULTS: Univariable and multivariable analysis demonstrate a statistically significant association between FNCLCC grade and both OS and PFS when comparing tumors by histologic grade. Of note, no deaths were observed in patients with grade 1 MPNST. Other variables associated with unfavorable outcomes include fragmented resection and primary site, with tumors in the extremities having favorable OS, but not PFS, when compared with those in truncal locations. Tumors in the head and neck had favorable PFS, but not OS, compared with those in the trunk. No statistically significant differences in OS or PFS were observed when comparing patient age and sex, tumor size at diagnosis, clinical setting (primary vs. type-1 neurofibromatosis vs. radiation associated) or history of neoadjuvant therapy. Interobserver agreement for FNCLCC grading of these tumors was considered good (S*=0.77, 95% confidence interval: 0.71-0.84). CONCLUSIONS: Association between FNCLCC grading and survival outcomes in MPNST suggests potential value to routinely grading these neoplasms. However, the subjectivity of the grading system, particularly when assigning a tumor differentiation score, may pose a challenge, especially in low and intermediate grade lesions.

Initial Presentation of Granulomatosis with Polyangiitis as Progressive Skull Base Osteomyelitis.

A healthy man in his 30s presented with a 2-week history of severe bitemporal pain and pressure. He was initially treated for presumed acute rhinosinusitis, but his symptoms continued to worsen and underwent endoscopic sinus surgery at an outside community facility. He developed left abducens nerve palsy postoperatively, and magnetic resonance imaging (MRI) demonstrated evidence of extensive skull base osteomyelitis. He was initiated on intravenous (IV) broad-spectrum antibiotics but was subsequently found to have prostatic and submandibular sterile fluid collections. The patient subsequently developed new right abducens and left vagal nerve palsies and underwent revision endoscopic sinus surgery. Pathology revealed extensive inflammation, necrotizing granulomas, and evidence of small and medium vessel vasculitis. Extensive laboratory workup was negative, except for anti-PR-3 antibody positivity. Given the characteristic findings on pathology and laboratory findings, the patient was diagnosed with granulomatosis with polyangiitis (GPA). High-dose glucocorticoid therapy as well as rituximab infusion were promptly initiated. He had marked improvement in his symptoms and resolution of his right CN VI palsy but left-sided CN VI and CN X palsies persisted. This patient presented without the typical rhinologic manifestations of GPA, and rather presented with progressive sinusitis, skull base osteomyelitis with associated cranial neuropathies, and aseptic systemic abscesses. Prompt diagnosis of GPA is particularly important in those with otorhinolaryngological manifestations, as early initial immunosuppressive therapy has been linked to lower relapse and mortality rates. Vigilance and early differentiation between GPA and other forms of sinusitis is of critical importance, particularly when symptoms are refractory to standard rhinosinusitis therapies.

Fatal infection with enterocolitis from methicillin-resistant Staphylococcus aureus and the continued value of culture in the era of molecular diagnostics.

MRSA enterocolitis is under-recognized in the setting of PCR testing. In this case report, we describe risk factors, the importance of stool culture, and the third published case of MRSA enterocolitis in a patient with leukemia. In addition, we performed a retrospective analysis of all stool cultures at our institution that have grown Staphylococcus aureus, and we describe an additional five cases. We also report the diagnostic yield of organisms detected by culture, but not on the FilmArray panel. While rare, these cases demonstrate that MRSA in stool may indicate a severe and potentially life-threatening infection, particularly in immunocompromised persons.

Massive exophytic malignant peripheral nerve sheath tumor.

We present a case of a solitary neurofibroma involving the right posterior shoulder of a 69-year-old man with degeneration into a massive, malignant peripheral nerve sheath tumor measuring more than 3 times the average reported size. The radiographic, magnetic resonance imaging, and computed tomographic features are compared with the gross appearance and pathology.

A clinico-epidemiological study of macular amyloidosis from north India.

BACKGROUND: Macular amyloidosis (MA) is the most subtle form of cutaneous amyloidosis, characterized by brownish macules in a rippled pattern, distributed predominantly over the trunk and extremities. MA has a high incidence in Asia, Middle East, and South America. Its etiology has yet to be fully elucidated though various risk factors such as sex, race, genetic predisposition, exposure to sunlight, atopy and friction and even auto-immunity have been implicated. AIM: This study attempts to evaluate the epidemiology and risk factors in the etiology of MA. MATERIALS AND METHODS: Clinical history and risk factors of 50 patients with a clinical diagnosis of MA were evaluated. Skin biopsies of 26 randomly selected patients were studied for the deposition of amyloid. RESULTS: We observed a characteristic female preponderance (88%) with a female to male ratio of 7.3:1, with a mean age of onset of MA being earlier in females. Upper back was involved in 80% of patients and sun-exposed sites were involved in 64% cases. Incidence of MA was high in patients with skin phototype III. Role of friction was inconclusive CONCLUSION: Lack of clear-cut etiological factors makes it difficult to suggest a reasonable therapeutic modality. Histopathology is not specific and amyloid deposits can be demonstrated only in a small number of patients. For want of the requisite information on the natural course and definitive etiology, the disease MA remains an enigma and a source of concern for the suffering patients.

Cutaneous Richter syndrome: report of 3 cases from one institution.

BACKGROUND: Richter syndrome (RS) is large-cell transformation of chronic lymphocytic leukemia (CLL). It commonly involves lymph nodes and bone marrow, but may rarely manifest in skin. Certain triggering factors, such as Epstein-Barr virus infection and p53 overexpression, have been implicated in the pathogenesis of RS. Here, we present 3 cases of cutaneous RS from our institution with a follow-up period of up to 8 years. OBJECTIVE: We present a series of cutaneous RS from a single institution with the longest follow-up period (up to 8 years) to date. METHODS: Clinical characteristics were collected and histopathological findings of skin biopsy specimens were analyzed. RESULTS: All 3 patients had prior CLL and later developed cutaneous RS lesions. The mean age at the diagnosis of cutaneous RS was 67 years old. The time intervals between CLL and cutaneous RS were 3 to 8 years. Skin biopsy specimens demonstrated dermal nodular or perivascular infiltrates of large B cells, showing similar immunophenotypes to the lesional cells in the original CLL. Overexpression of p53 and positive stain for Epstein-Barr virus--encoded small RNA was found in one patient. One patient remained alive 8 years after the diagnosis whereas the other two died of the disease at 5 years and 3 weeks, respectively, after the onset of cutaneous RS. LIMITATIONS: Three patients with RS were followed up for up to 8 years. CONCLUSIONS: Our findings suggested that, in contrast to extracutaneous RS, cutaneous RS generally has a less aggressive course with longer survival unless other worse prognostic factors are present.

Adverse host factors exacerbate occult HIV-associated nephropathy.

In the present study, we hypothesized that HIV-1-induced occult HIV-associated nephropathy (HIVAN) would become apparent in the presence of adverse host factors. To test our hypothesis, Vpr mice (which display doxycycline-dependent Vpr expression in podocytes) with two, three, and four copies of the angiotensinogen (Agt) gene (Vpr-Agt-2, Vpr-Agt-3, and Vpr-Agt-4) were administered doxycycline for 3 weeks (to develop clinically occult HIVAN) followed by doxycycline-free water during the next 3 weeks. Subsequently, renal biomarkers were measured, and kidneys were harvested for renal histology. Vpr-Agt-2 developed neither proteinuria nor elevated blood pressure, and displayed minimal glomerular and tubular lesions only, without any microcyst formation. Vpr-Agt-3 showed mild glomerular and tubular lesions and microcyst formation, whereas Vpr-Agt-4 showed moderate proteinuria, hypertension, glomerular sclerosis, tubular dilation, microcysts, and expression of epithelial mesenchymal transition markers. Vpr-Agt-4 not only displayed enhanced renal tissue expression of Agt, renin, and angiotensin-converting enzyme, but also had higher renal tissue concentrations of angiotensin II. Moreover, renal cells in Vpr-Agt-4 showed enhanced expression of transforming growth factor-ß, connective tissue growth factor, and vascular endothelial growth factor. These findings indicate that adverse host factors, such as the activation of the renin-angiotensin system, promote the progression of occult HIVAN to apparent HIVAN.

Perivascular epithelioid cell tumors (PEComas) of the head and neck: report of three cases and review of the literature.

PEComas are a family of neoplastic lesions that share overlapping morphology, immunohistochemistry, and ultrastructure that include angiomyolipoma, lymphangioleiomyomatosis, clear cell "sugar" tumor of the lung as well as similar tumors occurring in a variety of visceral, cutaneous and soft tissue sites throughout the body. The defining histopathological features are epithelioid cells with a perivascular distribution containing clear to pale eosinophilic granular cytoplasm and a round-to-oval centrally located nucleus with an inconspicuous nucleolus. Immunohistochemically, coexpression of melanocytic (HMB-45 and/or Melan-A) and myoid markers are characteristic. In the present study, we describe three PEComas occurring in the head and neck (nasal cavity and larynx) and discuss the behavior of these distinctive tumors and review the literature of head and neck PEComas. The importance of recognizing this entity will ensure its consideration in the differential diagnosis of tumors of the head and neck with a similar morphology. The histogenesis of PEComas still remains elusive and additional cases with a prolonged follow up remain important to accurately determine the behavior of these distinctive tumors. Complete surgical excision still remains the treatment of choice for histologically benign PEComas.