Histiocytoid Melanoma.

While most melanomas display well-characterised and readily recognised architectural and cytomorphological features, unusual variants can create diagnostic difficulties. Variants which mimic benign or reactive processes are particularly problematic. We report 5 cases of melanoma characterised by a subtle microscopic appearance reminiscent of a benign dermal histiocytic infiltrate, which we refer to as "histiocytoid melanoma." These lesions are characterised clinically by ill-defined areas of cutaneous pigmentation, which in several cases reached large proportions. Microscopically, there is a subtle interstitial pattern of infiltration by predominantly single cells with a histiocytoid morphology, often resembling melanophages. Immunohistochemical confirmation was typically required, with the cells showing positive labelling for Sox-10 as well as Melan-A. In several examples, the proliferation extended to clinically uninvolved surgical margins, necessitating multiple excisions, and many of our patients have experienced locoregional recurrence. However, none have developed distant metastases or died of melanoma. While uncommon, this subtle variant is important to recognise in order to ensure adequate histological clearance is obtained.

Rare case of bladder chondroma causing lower urinary tract symptoms.

An extraosseous or soft tissue chondroma is a rare, benign cartilaginous tumour characterised by the formation of mature hyaline cartilage. The majority of osseous chondromas are located within the medullary cavity of long bones. Soft tissue chondromas are extremely rare with only five cases affecting the bladder being reported in the literature. Soft tissue chondroma of the bladder is a rare cause of lower urinary tract symptoms and abdominopelvic pain. All reported cases of soft tissue chondromas of the bladder have occurred in women in their fifth to seventh decades of life. We describe the case of a 65-year-old woman diagnosed with a soft tissue chondroma of her bladder while being investigated for lower urinary tract symptoms.

Pure small cell carcinoma of the prostate preceded by acute zonal occult outer retinopathy: A case report.

INTRODUCTION: Pure small cell prostate cancer (SCPC) cases are very rare. Acute zonal occult outer retinopathy (AZOOR) has been described as a non-neoplastic retinopathy. We report the first case of pure SCPC preceded by AZOOR in the literature. CASE REPORT: A 59year old gentleman presented with an obstructed infected urinary system. He had a diagnosis of AZOOR 6 months ago that was investigated with full body imaging without any suspicious findings. However, the most recent CT findings demonstrated extensive disease dissemination. The patient underwent rigid cystoscopy and resection that confirmed a diagnosis of pure SCPC. DISCUSSION: AZOOR is a clinical syndrome of photopsia and rapid zonal field loss. The exact aetiology remains unknown and its association with malignancy remains contentious. Paraneoplastic manifestations of unexplained visual loss in SCPC are rare with only 2 cases reported in the literature. There are no cases demonstrating an association between AZOOR and SCPC. CONCLUSION: Pure SCPC is an aggressive malignancy with most cases presenting with extensive disease dissemination on diagnosis. Early detection has a role in improving prognosis but is challenging. Further research is required to establish a standard treatment protocol.

Gastric intraepithelial neoplasia in a Western population.

BACKGROUND AND STUDY AIMS: Descriptions of the natural history and endoscopic appearances of gastric dysplasia/intraepithelial neoplasia (IEN) that originate mainly from Europe. Currently, there are no Australian data available. We aimed to document endoscopic appearances and progression rates of gastric IEN and to determine the significance of indefinite for IEN. PATIENTS AND METHODS: This is a retrospective study, in which cases diagnosed with gastric IEN were identified between 2000 and 2009. Endoscopic appearances, progression rates to more advanced IEN or cancer, and long-term outcomes were recorded. RESULTS: A total of 160 cases with IEN (26.9% high grade, 57.5% low grade, 15.6% indefinite) were identified. The mean age was 67.8 years and 53.8% were men. Endoscopic lesions were polypoid in 29.4% and nonpolypoid in 70.6%. The most common location was the antrum (58.7%). Forty patients had an intervention and 76 underwent endoscopic follow-up only. Twenty-two cancers were diagnosed; three who had an intervention were diagnosed within 12 months, one with low-grade intraepithelial neoplasia developing a cancer after 9.9 years, and 13 undergoing surveillance only, were diagnosed with cancer within 12 months of index endoscopy. Five cases had cancer after a mean of 2.6 years. Forty-seven cases initially labelled as indefinite; following rereview 25 remained unchanged, 11 reclassified as negative for IEN, 10 as low grade, and one as high grade. Three of these cases developed cancer over the study period. CONCLUSION: We concluded that (a) majority of gastric IEN are associated with endoscopic lesions, (b) high rate of early cancer diagnosis was observed (c) rates of progression to cancer were lower than reported rates, and (d) indefinite for IEN is not innocuous requiring an expert pathologist's review.