A Case Report of Subcutaneous Ossifying Fibromyxoid Tumour of the Back.

Ossifying fibromyxoid tumour (OFMT) is a rare subcutaneous soft tissue neoplasm, with unclear lineage and intermediate differentiation. Typically presenting as a benign growth, however it can recur locally, and malignant variants have been reported. We present an unusual case of OFMT occurring as a subcutaneous mass on the right upper back. A 29-year-old gentleman presented with one-year history of a painless, slowly enlarging mass on his right upper back. He had no relevant medical history, was not on any medications, and had no family history of skin cancer. Physical examination revealed a 25mm x 25mm skin-coloured, stony-hard, well circumscribed mass. The initial clinical diagnosis was a calcified epidermoid cyst. The lesion was excised and sent for histopathology, which revealed well-circumscribed cellular spindle cells with low mitotic index. Immunohistochemistry showed variable S100 positivity. Due to its rarity, the diagnosis was delayed as the biopsy required a second opinion from a tertiary hospital. The final pathological diagnosis confirmed OFMT. This case describes the very rare presentation of OFMT in a dermatology clinic, highlighting the importance of recognising this neoplasm due to its potential for recurrence and metastasis. This unusual case of OFMT broadens the dermatological differential diagnosis for a subcutaneous mass.

A Solitary Fibrofolliculoma in Close Proximity to the Medial Canthus.

Fibrofolliculomas are benign connective tissue tumours of the hair follicle that typically present as multiple lesions over the head and neck. A solitary fibrofolliculoma is a rare entity and has not been previously described in the canthal region. The authors report an unusual case of a 43-year-old female who was found to have a solitary fibrofolliculoma located in close proximity to the medial canthus following an excision biopsy. Whilst rare, fibrofolliculomas should be considered in the differential diagnosis of an eyelid lesion.

Duchenne muscular dystrophy gene expression is an independent prognostic marker for IDH mutant low-grade glioma.

Alterations in the expression of the Duchenne muscular dystrophy (DMD) gene have been associated with the development, progression and survival outcomes of numerous cancers including tumours of the central nervous system. We undertook a detailed bioinformatic analysis of low-grade glioma (LGG) bulk RNAseq data to characterise the association between DMD expression and LGG survival outcomes. High DMD expression was significantly associated with poor survival in LGG with a difference in median overall survival between high and low DMD groups of over 7 years (P = < 0.0001). In a multivariate model, DMD expression remained significant (P = 0.02) and was an independent prognostic marker for LGG. The effect of DMD expression on overall survival was only apparent in isocitrate dehydrogenase (IDH) mutant cases where non-1p/19q co-deleted LGG patients could be further stratified into high/low DMD groups. Patients in the high DMD group had a median overall survival time almost halve that of the low DMD group. The expression of the individual DMD gene products Dp71, Dp71ab and Dp427m were also significantly associated with overall survival in LGG which have differential biological effects relevant to the pathogenesis of LGG. Differential gene expression and pathway analysis identifies dysregulated biological processes relating to ribosome biogenesis, synaptic signalling, neurodevelopment, morphogenesis and immune pathways. Genes spanning almost the entirety of chromosome 1p are upregulated in patients with high overall DMD, Dp71 and Dp427m expression which worsens survival outcomes for these patients. We confirmed dystrophin protein is variably expressed in LGG tumour tissue by immunohistochemistry and, overall, demonstrate that DMD expression has potential utility as an independent prognostic marker which can further stratify IDH mutant LGG to identify those at risk of poor survival. This knowledge may improve risk stratification and management of LGG.

Pyogenic Granuloma of the Penis: An Uncommon Lesion with Unusual Presentation.

We present the case of a 37-year-old man who presented with a penile lesion that engorged on erection. Ultrasound examination demonstrated vascularity of the lesion and the decision was made to perform a complete excision. Histological analysis confirmed the diagnosis of a pyogenic granuloma of the penis. Follow-up demonstrated no recurrence at 3 months.

Malignant Peripheral Nerve Sheath Tumor With Rhabdomyosarcomatous and Glandular Elements: Rare Epithelial Differentiation in a Triton Tumor.

Divergent differentiation occurs in a subset of malignant peripheral nerve sheath tumors (MPNST), but differentiation toward epithelial elements is unusual. MPNST with both heterologous rhabdomyosarcomatous differentiation (malignant Triton tumor), and glandular epithelial differentiation is exceedingly rare, with only 11 cases reported since 1973, and only 1 with histologically proven metastasis. We describe a case occurring in the mediastinum (between the ascending aorta and the main pulmonary artery) of a 40-year-old man with neurofibromatosis type-1. Despite treatment, the tumor metastasized to the right frontal lobe 16 months after diagnosis. Histologically, the primary neoplasm comprised cellular fascicles of atypical spindle cells, with discrete foci of well-formed or more primitive glandular epithelial structures, while the metastases comprised spindle cell sarcoma, including rhabdomyosarcoma, without epithelial elements. We review and discuss the literature on these little characterized neoplasms, including histology and clinical features, adding to the spectrum of documented cases of divergent epithelial differentiation in Triton tumor.