Merkel Cell Carcinosarcoma With a Bland Sarcomatous Component.

Merkel cell carcinoma with a sarcomatous component is very rare, with only 12 cases reported in the literature, often with overtly malignant myoid differentiation. We report a case of metastatic Merkel cell carcinosarcoma presenting in a lymph node 6 months after a diagnosis of cutaneous Merkel cell carcinoma with conventional histologic features. The metastatic lesion showed a unique biphasic appearance with admixed populations of neuroendocrine epithelial cells and fascicles of mitotically active spindle cells with mild cytological atypia.

Metastatic Melanoma to a Neurofibroma.

We present an extraordinary case of metastatic cutaneous melanoma to a pre-existing neurofibroma in a 75-year-old man with a history of primary invasive melanoma in an anatomically close vicinity. Histological examination of the metastatic melanoma showed a well-circumscribed intradermal nodule of frankly malignant epithelioid melanocytes without an intraepidermal component, surrounded and sharply demarcated from a diffuse spindle cell proliferation with morphological features of a neurofibroma. The spindle cell component showed bland cytologic features, with no mitotic activity or lymphocytic inflammation and no features of malignancy.

An Atypical Deep Penetrating Nevus With Mutations in Beta Catenin , BRAFV600E , and IDH1R132C in an 8-Year-Old Boy.

Deep penetrating nevus (DPN) is a pigmented melanocytic tumor which typically displays a wedge-shaped deep penetrating architecture. Some cases show a coexisting component resembling conventional melanocytic nevus. These morphological attributes are correlated with the acquisition of genomic alterations in the Wnt pathway on a background of underlying activating MAPK pathway mutations.

Factors in Psychiatric Admissions: Before and During the Covid-19 Pandemic.

Objective: The COVID-19 pandemic has impacted community mental health, but the effect on psychiatric admissions is unknown. We investigated factors contributing to acute psychiatric admissions, and whether this changed during the first UK lockdown.

Method: A retrospective case-note review study with an exploratory mixed-methods design to examine factors for psychiatric admissions following the first UK 2020 lockdown compared to the same time periods in 2019 and 2018.

Laboratory validation studies in Ki-67 digital image analysis of breast carcinoma: a pathway to routine quality assurance.

Ki-67 proliferative index (PI) has prognostic and predictive value in invasive breast carcinoma (IBC), but clinical uptake has been hampered by suboptimal accuracy, reproducibility and standardisation. Published guidelines have addressed pre-analytical and analytical factors to improve Ki-67 PI utility; however, practicalities of ongoing monitoring of Ki-67 PI quality in IBC reporting have not been established. We aimed to evaluate the internal and external quality of our established digital Ki-67 PI IBC reporting practice at a tertiary institution.

Unusual paediatric spinal myxopapillary ependymomas: Unique molecular entities or pathological variations on a theme?

Ependymomas are the commonest type of spinal glioma which represent a group of relatively benign tumours. Myxopapillary ependymoma (MPE) is a common variant found within the distal spinal cord around the conus. These two entities are clearly differentiated on the basis of their characteristic histological and molecular features.

Paediatric cutaneous adnexal tumours: a study of 559 cases.

Cutaneous adnexal tumours encompass a wide group of lesions with apocrine, eccrine, follicular, sebaceous and mixed differentiation. The large majority are benign and represent sporadic lesions, though malignant forms are occasionally encountered and some cases develop in the setting of inherited tumour syndromes. Accurate histological classification can be difficult as there are numerous histological appearances, many of which are individually uncommon, and complex, overlapping and historically variable nomenclature is typical.

Low risk, but not no risk, of umbilical hernia complications requiring acute surgery in childhood.

Aims: Umbilical hernias are a common finding in the paediatric community, with a preponderance to affect Afro-Caribbean and premature children. The rate of incarceration varies greatly between populations. Therefore, it is valuable to obtain some Australian data on this topic.