Histopathology reporting of temporal artery biopsy specimens for giant cell arteritis: results of a modified Delphi study.

The temporal artery biopsy (TAB) is regarded as the gold-standard test in the diagnosis of giant cell arteritis (GCA). There is a lack of agreement among experienced pathologists regarding the diagnostic features and classification of inflammation observed in TAB sections in the diagnosis of GCA. AIMS: The aim of this research study was to establish consensus on the key parameters which should be included in a standardised reporting proforma for TAB specimens. We specifically investigated factors pertaining to clinical information, specimen handling and microscopic pathological features. METHODS: A modified Delphi process, comprising three survey rounds and three virtual consensus group meetings, was undertaken by 13 UK-based pathology or ophthalmology consultants, with a 100% response rate across the three rounds. Initial statements were formulated after a literature review and participants were asked to rate their agreement using a nine-point Likert scale. Consensus was defined a priori as an agreement of ≥70% and individual feedback was provided after each round, together with data on the distribution of group responses. RESULTS: Overall, 67 statements reached consensus and 17 statements did not. The participants agreed on the core microscopic features to be included in a pathology report and felt that a proforma would facilitate consistent reporting practices. CONCLUSIONS: Our work revealed uncertainty surrounding the correlation between clinical parameters (eg, laboratory markers of inflammation and steroid therapy duration) and microscopic findings, and we propose areas for future research.

Clinical digital neuropathology: experience and observations from a departmental digital pathology training programme, validation and deployment.

AIM: To train and individually validate the neuropathologists in digital primary diagnosis and frozen section reporting using a novel protocol endorsed by the Royal College of Pathologists. The protocol allows early exposure to live digital reporting in a risk mitigated environment. METHODS: Two specialist neuropathologists completed training in the use of a digital microscopy system for primary neuropathological diagnosis and frozen section assessment. Participants were exposed to training sets of 20 histology cases and 10 frozen sections designed to help them identify their personal digital diagnostic pitfalls. Following this, the pathologists viewed 340 live, complete neuropathology cases. All primary diagnoses were made on digital slides with immediate glass slide reconciliation before final case sign-out. RESULTS: There was 100% clinical concordance between the digital slide and glass slide assessment of frozen section cases for each pathologist, and these assessments corresponded with the ground truth diagnoses obtained from examination of definitive histology. For primary diagnosis, there was complete clinical concordance between digital slide and glass slide diagnosis in 98.1% of cases. The majority of discordances were related to grading differences attributable to mitotic count differences. CONCLUSION: Neuropathologists can develop the ability to make primary digital diagnosis competently and confidently following a course of individual training and validation.

Thoracic Intradural Extramedullary Ependymoma with Anaplastic Transformation: Case Report and Discussion.

BACKGROUND: Intradural extramedullary spinal ependymomas arising from outside the region of the conus medullaris are rare clinical entities, and anaplastic transformation of these lesions is even more exceptional. CASE DESCRIPTION: We report on a case of an intradural extramedullary T5-T6 ependymoma that underwent gross total resection. Histologic analysis of the initial tumor revealed a World Health Organization grade 2 ependymoma. Two years after initial surgical resection, there was radiologic recurrence and a re-do resection was performed with subsequent spinal stabilization. Histologic analysis of the recurrent tumor revealed a World Health Organization grade 3 ependymoma. After surgery the patient received radiotherapy, and he remains disease free at 2 years following his second surgery. In addition, we employed carbon fiber screws and rods for stabilization in his second operation to reduce artefact on follow-up imaging. CONCLUSIONS: We advocate that primary spinal ependymomas should be within the differential of intradural extramedullary lesions arising outside the region of the conus medullaris.

Diagnostic surprise in an evisceration specimen.

AIMS AND PURPOSE: To report a rare ocular tumor discovered incidentally after evisceration of a painful blind eye. METHODS: Observational case report. RESULTS: A 67-year-old Caucasian lady presented for elective evisceration of chronically irritable phthisical right eye. A history of bilateral retinal detachment surgery 34 years prior followed by phthisis of the right eye was noted. The patient was a smoker but otherwise fit and well. Intra-operatively, the ocular contents were felt to be unusual with hard deeply pigmented lumps being present in the eviscerated tissue. The specimen was sent for histopathology. This was reported as a primary adenocarcinoma of the retinal pigment epithelium after expert histological opinion. The possibilities of a secondary adenocarcinoma with possible primary sites as lung, breast or kidney were ruled out by immuno-histochemical techniques. The patient underwent extensive systemic screening including a whole body CT scan. Exhaustive investigations have not found any other tumor site. CONCLUSION: In the absence of a recognizable source of metastasis, a diagnosis of primary ocular adenocarcinoma has been made with retinal pigment epithelium being the possible site of origin. Literature review shows that primary ocular adenocarcinoma arising from neuroepithelium is a rare but recognized occurrence especially in longstanding blind eyes. This case highlights the importance of routine histopathological examination of eviscerated ocular contents, especially in long standing blind eyes.