Sudipta Sinnya

Automated Detection of Actinic Keratoses in Clinical Photographs

Background Clinical diagnosis of actinic keratosis is known to have intra- and inter-observer variability, and there is currently no non-invasive and objective measure to diagnose these lesions. Objective The aim of this pilot study was to determine if automatically detecting and circumscribing actinic keratoses in clinical photographs is feasible. Methods Photographs of the face and dorsal forearms were acquired in 20 volunteers from two groups: the first with at least on actinic keratosis present on the face and each arm, the second with no actinic keratoses. The photographs were automatically analysed using colour space transforms and morphological features to detect erythema. The automated output was compared with a senior consultant dermatologist’s assessment of the photographs, including the intra-observer variability. Performance was assessed by the correlation between total lesions detected by automated method and dermatologist, and whether the individual lesions detected were in the same location as the dermatologist identified lesions. Additionally, the ability to limit false positives was assessed by automatic assessment of the photographs from the no actinic keratosis group in comparison to the high actinic keratosis group. Results The correlation between the automatic and dermatologist counts was 0.62 on the face and 0.51 on the arms, compared to the dermatologist’s intra-observer variation of 0.83 and 0.93 for the same. Sensitivity of automatic detection was 39.5% on the face, 53.1% on the arms. Positive predictive values were 13.9% on the face and 39.8% on the arms. Significantly more lesions (p<0.0001) were detected in the high actinic keratosis group compared to the no actinic keratosis group. Conclusions The proposed method was inferior to assessment by the dermatologist in terms of sensitivity and positive predictive value. However, this pilot study used only a single simple feature and was still able to achieve sensitivity of detection of 53.1% on the arms.This suggests that image analysis is a feasible avenue of investigation for overcoming variability in clinical assessment. Future studies should focus on more sophisticated features to improve sensitivity for actinic keratoses without erythema and limit false positives associated with the anatomical structures on the face.

Noninvasive methods for the assessment of photoageing

Although histopathological dermal elastosis is the current gold standard for the diagnosis of photoageing, noninvasive methods for quantifying the amount of photodamage to skin are clearly preferable. This study is the first to survey five noninvasive methods of assessing photoageing (clinical examination, spectrophotometry, skin surface topography, reflectance confocal microscopy and fluorescence lifetime imaging microscopy) in the same individual. Measurements for each noninvasive method were compared across nine individuals from three participant groups (‘younger’, ‘older’ and ‘photodamaged’) in UV‐protected volar and UV‐exposed dorsal forearm skin. Overall, participants in the younger group had the lowest measures of photodamage, while those in the photodamaged group had the highest, as indicated by each modality. The five noninvasive strategies surveyed in this study may demonstrate potential as a suitable methodology for the quantification of photoageing. The advantage of such noninvasive methods is that they allow for skin visualisation in vivo and repeated assessments of the same site. The main limitation of this study was its small sample size, which may have precluded many findings of statistical significance.

A randomized, phase IIa exploratory trial to assess the safety and preliminary efficacy of LEO 43204 in patients with actinic keratosis.

LEO 43204 is a novel ingenol derivative in development for the treatment of actinic keratosis.

Histopathology and reflectance confocal microscopy features of photodamaged skin and actinic keratosis

Actinic keratosis (AK) usually co‐exists in areas of severe photodamage, but the clinical applicability of reflectance confocal microscopy (RCM) in diagnosing AK currently depends on a set of parameters yet to be defined in comparison to photodamaged skin (PD).

RNA-seq reveals more consistent reference genes for gene expression studies in human non-melanoma skin cancers

Identification of appropriate reference genes (RGs) is critical to accurate data interpretation in quantitative real-time PCR (qPCR) experiments. In this study, we have utilised next generation RNA sequencing (RNA-seq) to analyse the transcriptome of a panel of non-melanoma skin cancer lesions, identifying genes that are consistently expressed across all samples. Genes encoding ribosomal proteins were amongst the most stable in this dataset. Validation of this RNA-seq data was examined using qPCR to confirm the suitability of a set of highly stable genes for use as qPCR RGs. These genes will provide a valuable resource for the normalisation of qPCR data for the analysis of non-melanoma skin cancer.

The ratio of non-hyperkeratotic and hyperkeratotic actinic keratosis in a high-risk non-melanoma skin cancer cohort in Queensland.

References 1 Swift JA. Fine details on the surface of human hair. Int J Cosmet Sci 1991; 13: 143–159. 2 Tomes C, Jones JT, Carr CM, Jones D. Three-dimensional imaging and analysis of the surface of hair fibres using scanning electron microscopy. Int J Cosmet Sci 2007; 29: 293–299. 3 Ferreira O, Baudrier T, Mota A et al. Onychotrychia?: subungual hair follicle as another cause of longitudinal melanonychia or pigmentation – hair follicle as cause of melanononychia. J Eur Acad Dermatol Venereol 2010; 24: 1238–1239. 4 C erman AA. Subungual ectopic hair. J Eur Acad Dermatol Venereol 2011; 25: 1115–1116. 5 Emeksiz MC, Uzar KM. Subungual ectopic hair (Onychotrychia). J Eur Acad Dermatol Venereol 2014; 28: 1263–1264. 6 Nagtzaam IF, van der Velden JJ, Kelleners-Smeets NW, Frank J. Onycholysis associated with subungual manifestation of barber’s hair sinus. Int J Dermatol 2007; 46(Suppl 3): 48–49.

Verruciform xanthoma of the penis: a rare Australian case

We present a case of verruciform xanthoma ((VX) of the penis in an elderly man in whom an asymptomatic papule on his foreskin was noted during a routine clinical examination. VX is a rare, benign condition with a predilection for the oral cavity and clinically presents as isolated, painless mucosal lesions with a verrucoid surface. Accurate diagnosis is important in avoiding aggressive surgical management of this relatively rare condition.

High incidence of primary melanomas in an MC1R RHC homozygote/CDKN2A mutant genotype patient

Melanoma incidence in Australia remains the highest in the world; hence understanding its causation is paramount for future therapeutic developments. Multiple primary melanomas are also common occurrences among the Australian population with identified risk factors such as personal and family history of melanoma, fair skin type, dysplastic naevus syndrome and history of significant ultraviolet exposure. The roles of both environmental and genetic factors have been elucidated in melanoma development, but the synergy of interactions between the two remains complex given the heterogeneous nature of the disease. We present a rare case of a 57-year-old female with 20 cutaneous melanomas and review the role of genetic and environmental factors in development of her multiple primary melanomas.

Oral mucocoeles in chronic graft-versus-host-disease: report of a case following lung transplantation

1. Ang GC, Roenigk RK, Otley CC et al. More than 2 decades of treating atypical fibroxanthoma at mayo clinic: what have we learned from 91 patients? Dermatol. Surg. 2009; 35: 765–72. 2. Starink TM, Hausman R, Van Delden L et al. Atypical fibroxanthoma of the skin: presentation of 5 cases and review of the literature. Br. J. Dermatol. 1977; 97: 167–77. 3. Davis JL, Randle HW, Zalla MJ et al. A comparison of Mohs micrographic surgery and wide excision for the treatment of atypical fibroxanthoma. Dermatol. Surg. 1997; 23: 105–10.

Expression of Bcl-xL and Mcl-1 in the Nonmelanoma Skin Cancers of Renal Transplant Recipients

OBJECTIVES This study aims to investigate how immunosuppression influences the protein expression of antiapoptotic members of the Bcl-2 family-namely, Bcl-xL and Mcl-1-in nonmelanoma skin cancer (NMSC) and the peritumoral epidermis of renal transplant recipients. METHODS NMSC and peritumoral epidermis protein expression of Bcl-xL and Mcl-1 were assessed by immunohistochemistry in renal transplant recipients receiving tacrolimus or sirolimus and the general population not receiving immunosuppression. RESULTS NMSC from renal transplant recipients compared with patients not receiving immunosuppressant medications had a reduced Bcl-xL expression intensity (P = .042). Mcl-1 expression intensity in NMSC was decreased in tacrolimus-treated patients compared with sirolimus-treated patients and the nonimmunosuppressed population (P = .024). Bcl-xL expression intensity was increased in peritumoral epidermis compared with NMSC (P = .002). CONCLUSIONS It was shown for the first time that Bcl-xL and Mcl-1 expression are widespread in the peritumoral epidermis and NMSC of renal transplant recipients. Importantly in NMSC, Bcl-xL expression was reduced with immunosuppression exposure, and Mcl-1 expression was reduced in tacrolimus-treated compared with sirolimus-treated patients.