Desmoplastic Melanoma Masquerading as Neurofibroma.

Desmoplastic melanoma (DMM) is a rare variant of melanoma that presents major diagnostic challenges. It can mimic both benign or other malignant tumors and may be easily confused by clinicians and pathologists. We report a patient who presented with a pink-colored papule on the left lateral neck. Histopathology revealed a nodular spindle cell tumor in the dermis resembling a neurofibroma at low power. However, higher-power evaluation and the use of immunohistochemical staining confirmed the diagnosis of DMM.We present this case to highlight the ongoing challenges of diagnosing DMM both clinically and histologically and to review the salient features of this often benign-appearing tumor. Advancing age, male gender, and head and neck location are associated with an increased risk of DMM-specific death. It is important that new or changing lesions in the correct cohort and location are biopsied promptly.

Cutaneous insulin-derived amyloidosis presenting as hyperkeratotic nodules.

Amyloidosis consists of approximately 30 protein-folding disorders in which a specific soluble precursor protein aggregates to form the insoluble fibrils of amyloid. Insulin is the hypothesized precursor protein in localized cutaneous insulin-derived (AIns) amyloidosis. Amyloid deposition at insulin injection sites can interfere with absorption, leading to poor glucose control. Despite the increasing prevalence of diabetes mellitus and insulin use, there is a paucity of published cases of AIns amyloidosis and a lack of awareness of this condition among both dermatologists and general practitioners. We report 2 patients with insulin-dependent diabetes who developed hyperkeratotic nodules at insulin injection sites. Our cases complement the current data on iatrogenic amyloidosis and provide insight into this likely underreported phenomenon.

Comparison of an automated confrontation testing device versus finger counting in the detection of field loss.

PURPOSE: The aim of this study was to compare an automated confrontation visual field testing (ACV) device with traditional finger-counting confrontation visual field testing (FCV). METHODS: Forty-five eyes of 45 subjects with glaucoma, 5 eyes of 5 subjects with neurologic disease and 15 eyes of 15 normal subjects (age matched to the subjects with glaucoma by frequency) were tested on both ACV and FCV. All subjects with glaucoma and neurologic disease had visual field loss on white-on-white Humphrey perimetry (HVF). The FCV was performed in 8 meridians in a normally lighted room, whereas ACV was performed in a darkened room. The ACV device consisted of a black rectangular box with 4 1.0-mm red light-emitting diodes at each corner and a fixation hole at the center. Four automated randomized presentations were presented, and the subject was asked to identify the number of red lights seen (from 1 to 4). Any point missed on any of the presentations on either test was recorded as a failure. RESULTS: All normal subjects passed both tests. FCV detected field loss in 33.0% of glaucomatous eyes, whereas ACV detected field loss in 58% of glaucomatous eyes (P < 0.001). Subjects with glaucoma who passed FCV but failed ACV had an average mean deviation of -7.77 dB on HVF, compared with subjects who failed both FCV and ACV, who had an average mean deviation of -19.74 dB on HVF (P < 0.001). All subjects with absolute visual field loss because of advanced glaucoma or neurologic disease failed both tests. No subject who passed ACV failed FCV. CONCLUSIONS: Gross confrontation visual field testing using an automated testing device has a greater sensitivity in the detection of moderate visual field loss than finger counting confrontation visual fields.