Gene expression profiling of perineural invasion in head and neck cutaneous squamous cell carcinoma

Perineural invasion (PNI) is frequently associated with aggressive clinical behaviour in head and neck cutaneous squamous cell carcinoma (HNcSCC) leading to local recurrence and treatment failure. This study evaluates the gene expression profiles of HNcSCC with PNI using a differential expression analysis approach and constructs a tailored gene panel for sensitivity and specificity analysis. 45 cases of HNcSCC were stratified into three groups (Extensive, Focal and Non PNI) based on predefined clinicopathological criteria. Here we show HNcSCC with extensive PNI demonstrates significant up- and down-regulation of 144 genes associated with extracellular matrix interactions, epithelial to mesenchymal transition, cell adhesion, cellular motility, angiogenesis, and cellular differentiation. Gene expression of focal and non PNI cohorts were indistinguishable and were combined for further analyses. There is clinicopathological correlation between gene expression analysis findings and disease behaviour and a tailored panel of 10 genes was able to identify extensive PNI with 96% sensitivity and 95% specificity.

Altered axonal excitability properties in facial palsy

INTRODUCTION

Axonal excitability measures give insight into the biophysical properties of peripheral nerve axons. In this study we applied these techniques to the study of facial palsy.

METHODS

Thirty patients with established facial palsy due to unresolved Bell's palsy or herpes zoster (>6 months duration), tumor invasion of the facial nerve, or traumatic facial nerve injury were assessed using facial nerve excitability techniques.

RESULTS

Full recordings were obtained in 23 patients (15 unrecovered Bell's palsy or herpes zoster, 5 trauma, 3 tumor-related). Compared with normal controls, the facial palsy group demonstrated changes in stimulus response properties, threshold electrotonus, refractoriness, superexcitability, and I/V slope. Depolarizing threshold electrotonus distinguished between viral and non-viral etiologies on subgroup analysis.

DISCUSSION

In this cross-sectional study, established facial palsy demonstrated findings similar to those seen in studies of regenerated axons. The improved understanding of underlying axonal characteristics offered by the technique may guide future treatment. Muscle Nerve 57: 268-272, 2018.

Salivary duct carcinoma: Clinicopathologic features, morphologic spectrum, and somatic mutations

BACKGROUND

Accurate diagnosis of salivary duct carcinoma requires a high index of suspicion and clinicopathologic correlation. Hallmark genetic changes that may provide novel therapeutic options are being explored.

METHODS

One hundred ninety salivary gland malignancies at Royal Prince Alfred Hospital (from 1989-2014) were reviewed. Human epidermal growth factor receptor 2 (HER2) and androgen receptor status were determined along with multigene profiling.

RESULTS

Twenty-three salivary duct carcinomas were identified, predominantly in men in their fifth to ninth decades of life. Facial nerve palsy (12%) and cervical lymph node metastases (82%) were present, and 96% received postoperative adjuvant therapy. Histologically, the tumors resembled high-grade invasive and in situ ductal carcinoma of the breast. Micropapillary, papillary, sarcomatoid, oncocytic, and mucinous variants were seen. The tumors showed androgen receptor (70%), HER2 amplification (30%), and HRAS, AKT1, PIK3CA, and NRAS mutations (22%; cumulative). The 5-year disease-free survival was 36%.

CONCLUSION

Salivary duct carcinoma demonstrates a wide histopathologic spectrum. Treatment strategies need to take androgen receptor, HER2 amplification, and PIK3CA mutation into account. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1838-E1847, 2016.

Bell's palsy: aetiology, clinical features and multidisciplinary care

Bell's palsy is a common cranial neuropathy causing acute unilateral lower motor neuron facial paralysis. Immune, infective and ischaemic mechanisms are all potential contributors to the development of Bell's palsy, but the precise cause remains unclear. Advancements in the understanding of intra-axonal signal molecules and the molecular mechanisms underpinning Wallerian degeneration may further delineate its pathogenesis along with in vitro studies of virus-axon interactions. Recently published guidelines for the acute treatment of Bell's palsy advocate for steroid monotherapy, although controversy exists over whether combined corticosteroids and antivirals may possibly have a beneficial role in select cases of severe Bell's palsy. For those with longstanding sequaelae from incomplete recovery, aesthetic, functional (nasal patency, eye closure, speech and swallowing) and psychological considerations need to be addressed by the treating team. Increasingly, multidisciplinary collaboration between interested clinicians from a wide variety of subspecialties has proven effective. A patient centred approach utilising physiotherapy, targeted botulinum toxin injection and selective surgical intervention has reduced the burden of long-term disability in facial palsy.

Mammary analogue secretory carcinoma: an evaluation of its clinicopathological and genetic characteristics

Mammary analogue secretory carcinoma (MASC) is a recently described salivary gland malignancy. We evaluate the clinicopathological characteristics and long-term clinical behaviour of MASCs. A total of 190 primary salivary gland malignancies at a single institution were reviewed along with relevant immunohistochemical and fluorescent in situ hybridisation (FISH) studies to identify MASCs. Nine MASCs were identified predominantly in the parotid with an equal incidence in men and women and mean age of 36 years. The tumour size ranged from 14 to 50 mm (mean 22 mm). MASCs were composed of monotonous cells with vacuolated eosinophilic cytoplasm and a small nucleus with a distinctive nucleolus. All cases showed immunoreactivity with S-100, MUC4, CK7 and mammoglobin, and lacked immunoreactivity with DOG1, p63, CK5/6 and calponin. ETV6 rearrangement was seen in all cases. No mutations were identified using the OncoCarta Panel v1.0 Kit. Follow up was available for 0.4 to 22 years (median 4 years). Intraparotid lymph node involvement and local recurrence were seen in one patient each. There were no distant metastases. MASCs have specific histopathological features and immunohistochemical profile that distinguish them from their mimics. FISH plays a confirmatory role. An indolent long-term clinical course was observed in this cohort despite involvement of intraparotid lymph node and microscopically involved/close margins.