Cartilage-like composition of keloid scar extracellular matrix suggests fibroblast mis-differentiation in disease

Following wound damage to the skin, the scarring spectrum is wide-ranging, from a manageable normal scar through to pathological keloids. The question remains whether these fibrotic lesions represent simply a quantitative extreme, or alternatively, whether they are qualitatively distinct. A three-way comparison of the extracellular matrix (ECM) composition of normal skin, normal scar and keloids was performed using quantitative discovery-based proteomics. This approach identified 40 proteins that were significantly altered in keloids compared to normal scars, and strikingly, 23 keloid-unique proteins. The major alterations in keloids, when functionally grouped, showed many changes in proteins involved in ECM assembly and fibrillogenesis, but also a keloid-associated loss of proteases, and a unique cartilage-like composition, which was also evident histologically. The presence of Aggrecan and Collagen II in keloids suggest greater plasticity and mis-differentiation of the constituent cells. This study characterises the ECM of both scar types to a depth previously underappreciated. This thorough molecular description of keloid lesions relative to normal scars is an essential step towards our understanding of this debilitating clinical problem, and how best to treat it.

Conventional and combination topical photodynamic therapy for basal cell carcinoma: systematic review and meta-analysis

BACKGROUND

Topical photodynamic therapy (PDT) is an established treatment option for low-risk basal cell carcinoma (BCC).

OBJECTIVES

To compare efficacy, cosmesis and tolerability of PDT for BCC with alternative treatments.

METHODS

MEDLINE, PubMed, Embase and CENTRAL databases were searched from inception until 1 September 2017. Included studies were randomized controlled trials (RCTs) of PDT for nodular (n) and superficial (s) BCC reporting at least one of the following outcomes: clearance at 3 months and sustained at 1 or 5 years; recurrence at ≥ 1 year; cosmesis; adverse events; tolerability.

RESULTS

From 2331 search results, 15 RCTs (2327 patients; 3509 BCCs) were included. PDT efficacy (5-year sustained clearance) was high but inferior to excisional surgery [nBCC pooled risk ratio (RR) 0·76; 95% confidence interval (CI) 0·63-0·91], and without re-treatment of partially responding lesions, was modestly inferior to imiquimod (sBCC: RR 0·81; 95% CI 0·70-0·95) and similar to fluorouracil (sBCC: RR 0·88; 95% CI 0·75-1·04). Five-year sustained clearance was inferior with conventional vs. fractionated PDT (sBCC: RR 0·76; 95% CI 0·68-0·84). PDT cosmesis was superior to surgery (sBCC: RR 1·68, 95% CI 1·32-2·14; nBCC: RR 1·82, 95% CI 1·19-2·80) and cryosurgery (BCC: RR 3·73, 95% CI 1·96-7·07), and without re-treatment of partially responding lesions was similar to imiquimod (sBCC: RR 1·01, 95% CI 0·85-1·19) and fluorouracil (sBCC: RR 1·04, 95% CI 0·88-1·24). Peak pain was higher but of shorter duration with PDT than topical treatments. Serious adverse reactions were rarer with PDT than imiquimod (sBCC: RR 0·05, 95% CI 0·00-0·84) and fluorouracil (sBCC: RR 0·11, 95% CI 0·01-2·04). Combination PDT regimens demonstrated reduced recurrence and improved cosmesis; however, results from these small studies were often nonsignificant.

CONCLUSIONS

PDT is an effective treatment for low-risk BCC, with excellent cosmesis and safety. Imiquimod has higher efficacy than single-cycle PDT but more adverse effects. Highest efficacy is with excisional surgery. Fractionated and combination PDT options warrant further study.

Laser Corrective Surgery with Fractional Carbon Dioxide Laser Following Full-thickness Skin Grafts

Full-thickness skin grafts (FTSGs) are frequently used to treat patients with burn injuries and to repair defects rendered by excisional (including Mohs) surgery. The evidence for corrective laser surgery after scar formation is well established. With regard to laser treatment of FTSG, the evidence is sparse. Laser treatment after FTSG is a novel concept, with minimal literature. We present a case series, one of the first to our knowledge, of the treatment of FTSG with fractional CO₂ laser in five patients after Mohs surgery.

Use of a novel 1-hour protocol for rapid frozen section immunocytochemistry, in a case of squamous cell carcinoma treated with Mohs micrographic surgery

For squamous cell carcinoma (SCC) treated using Mohs micrographic surgery (MMS), interpretation of haematoxylin and eosin-stained frozen sections can be challenging. In these situations, ancillary use of immunostaining is a useful tool for the Mohs surgeon. However, use of immunostaining in MMS laboratories is limited, mainly because current manual immunostaining platforms are subject to operator error, and automated immunostaining, albeit accurate, is too slow for inclusion in MMS. In this report, we describe a novel 1-hour protocol for rapid frozen section immunocytochemistry, using the pancytokeratin markers AE1/AE3. This protocol has been specifically designed to integrate the speed of manual techniques and the accuracy of automated platforms, making it a valuable addition to the MMS laboratory. We propose that in selected or histologically challenging cases, there is a role for the use of this novel protocol, allowing the Mohs surgeon to more confidently declare tumour clearance, thus preventing further unnecessary surgery and preserving healthy tissue.

Spatial constraints govern competition of mutant clones in human epidermis

Deep sequencing can detect somatic DNA mutations in tissues permitting inference of clonal relationships. This has been applied to human epidermis, where sun exposure leads to the accumulation of mutations and an increased risk of skin cancer. However, previous studies have yielded conflicting conclusions about the relative importance of positive selection and neutral drift in clonal evolution. Here, we sequenced larger areas of skin than previously, focusing on cancer-prone skin spanning five decades of life. The mutant clones identified were too large to be accounted for solely by neutral drift. Rather, using mathematical modelling and computational lattice-based simulations, we show that observed clone size distributions can be explained by a combination of neutral drift and stochastic nucleation of mutations at the boundary of expanding mutant clones that have a competitive advantage. These findings demonstrate that spatial context and cell competition cooperate to determine the fate of a mutant stem cell.

Deep sequencing technologies allow for the investigation of clonal evolution in human cancers. Here the authors, combining sequencing data from human skin with mathematical modelling and simulations, suggest that the spatial context of a mutation with respect to other mutant clones may lead to differential clonal evolution.

New embedding and staining systems PrestoCHILL and Presto stainer for application in the advancement of Mohs micrographic surgery

BACKGROUND

Mohs micrographic surgery (MMS) involves evaluation of frozen tissue sections to determine complete circumferential and deep tissue margin clearance of skin tumours. PrestoCHILL and Presto stainer devices are two new innovative tools which bring benefits of automation, speed and efficiency to the preparation of frozen section analysis in MMS. The devices were assessed at Viapath's Tissue Science Mohs laboratory at Guy's Cancer Centre.

MATERIAL AND METHODS

A total of 279 samples from 10 anatomically different facial sites. These included nose (95), lip (24), forehead (47), cheek (25), eyelids (34), temple (9), chin (15), ear (17), scalp (6) and neck (7). These were analysed using both devices simultaneously.

RESULTS

The PrestoCHILL device was measured for accuracy of tissue orientation by determining how many of the cases examined microscopically had complete margin and full epidermis preservation. The precision and reproducibility of the Presto stainer was evaluated by the consistency of achieving ideal standards of staining quality as defined by the department's internal quality control check, on stained sections examined and evaluated microscopically. The mean (standard deviation) score for accuracy for the PrestoCHILL across all tissue facial sites was 93.5 (11)%; the mean (standard deviation) score for precision/reproducibility of the Presto stainer was 96.5 (11)% (both p < 0.05).

CONCLUSION

The devices combined offer an assured accuracy and precision performance, which is reproducible across all facial tissue types examined. The devices represent a key step forward in the introduction of improved automated embedding and staining procedures within MMS.

Identification of emotion associated brain functional network with phase locking value

Recognition of discriminative brain functional network pattern and regions corresponding to emotions are important in understanding the neuron functional network underlying the human emotion process. Emotion models mapping onto brain is possible with the help of emotion-specific network patterns and its corresponding brain regions. This paper presents a method to identify emotion related functional connectivity pattern and their distinctive associated regions using EEG phase synchrony (phase locking value (PLV)) connectivity analysis. The emotion-specific channel pairs, reactive band, and synchrony related locations are identified based on the network dissimilarities between emotion and rest tasks. With the most reactive pairs identified, the emotion-specific functional network is formed. The proposed method is validated on `database for emotion analysis using physiological signals (DEAP)' that confirms the distinct nature of identified functional connectivity pattern and the regions corresponding to the emotion.

The use of lasers in cutaneous sarcoid: Is there a role?

Sarcoid is a granulomatous disease that can affect the skin solely or as part of a systemic involvement. Cutaneous lesions of sarcoid may be difficult to treat and lasers are rarely used. In this article we report our case series and review the literature on the use of lasers in cutaneous sarcoid.

The use of lasers in Becker's naevus: An evidence-based review

Becker's naevus is a hamartoma that often appears during puberty. Clinically this presents with a pigmented and often hairy patch most often on the shoulders. Treatment has always been challenging and lasers are often used with mixed results. This article reviews the evidence of all the laser treatments used in Becker's naevus and analyses the findings from the published studies and trials.

Photodynamic Therapy Followed by Mohs Micrographic Surgery Compared to Mohs Micrographic Surgery Alone for the Treatment of Basal Cell Carcinoma: Results of a Pilot Single-Blinded Randomised Controlled Trial

Introduction:

Basal cell carcinoma is a common cutaneous malignant tumour. Surgical excision is the “gold standard” treatment for most subtypes, with Mohs micrographic surgery (MMS) offering the highest cure rate. Other treatment modalities used include photodynamic therapy (PDT).

Background:

We aimed to study the efficacy of combining MMS with PDT to see whether this would reduce the number of stages and final defect size when compared with MMS alone.

Materials and Methods:

Our study was a single-centre, single-blinded, randomised and controlled pilot study involving a total of 19 patients. Nine patients were randomised to pre-treatment with PDT followed by MMS of whom two withdrew; the remaining 10 patients were randomised to the MMS alone. Follow-up visits were arranged at 3 and 6 months post-surgery.

Results:

In the PDT arm, five out of the seven treated patients (71%) had their initial tumour size decreased following PDT treatment prior to MMS. The average number of stages in the PDT arm was 1.85, compared to 2.5 in the MMS arm. The average number of sections in the PDT arm was 4.2, in comparison to 5.2 in the MMS arm.

Conclusion:

Our pilot study showed a promising but limited role for PDT as an adjunct in MMS in the treatment of selected cases of basal cell carcinomas. Larger trials, preferably multi-centred are required to further examine the role of this combination therapy.

Multiple cutaneous, oropharyngeal and pulmonary nodules

Erdheim-Chester disease (ECD) is a rare non-Langerhans cell histiocytosis defined by heterogeneous multiorgan involvement. Due to the rarity of this disease strong evidence-based therapies have yet to be established and prognosis has previously been considered to be poor, with more than half of patients dying within 3 years of initial presentation. We describe an 86-year-old woman with a 34-year history of extensive cutaneous and internal nodules with typical pathological and immunophenotypical (CD68(+) /CD1a(-) ) features of ECD without evidence of the BRAF V600E mutation. The cosmetic appearance of cutaneous nodules and hoarse voice caused by vocal cord nodules has been managed surgically. More aggressive therapies reported for ECD were trialled for this patient, such as radiotherapy and interferon-α, with no response. This case demonstrates a relatively good prognosis in ECD that has been managed conservatively.

Lentigo maligna mimicking invasive melanoma in Mohs surgery: a case report

Lentigo maligna is a lentiginous proliferation of atypical melanocytes confined to the epidermis, typically on chronically sun-damaged skin. Following biopsy and exclusion of invasive disease, therapy may involve Mohs surgery, topical treatment or radiotherapy. However, lentigo maligna often involves adnexal structures, creating histological difficulty in distinguishing these foci from invasive melanoma. We present a case in which, during Mohs excision, a nodule of severely atypical melanocytes appeared to lie within the dermis, potentially altering treatment and prognosis. The use of laminin-5 provided a means of resolving this diagnostic dilemma, facilitating continuation of Mohs surgery until tumour clearance was achieved.

Automated registration of optical coherence tomography and dermoscopy in the assessment of sub-clinical spread in basal cell carcinoma

Optical coherence tomography (OCT) has been shown to be of clinical value in imaging basal cell carcinoma (BCC). A novel dual OCT-video imaging system, providing automated registration of OCT and dermoscopy, has been developed to assess the potential of OCT in measuring the degree of sub-clinical spread of BCC. Seventeen patients selected for Mohs micrographic surgery (MMS) for BCC were recruited to the study. The extent of BCC infiltration beyond a segment of the clinically assessed pre-surgical border was evaluated using OCT. Sufficiently accurate (<0.5 mm) registration of OCT and dermoscopy images was achieved in 9 patients. The location of the OCT-assessed BCC border was also compared with that of the final surgical defect. Infiltration of BCC across the clinical border ranged from 0 mm to >2.5 mm. In addition, the OCT border lay between 0.5 mm and 2.0 mm inside the final MMS defect in those cases where this could be assessed. In one case, where the final MMS defect was over 17 mm from the clinical border, OCT showed >2.5 mm infiltration across the clinical border at the FOV limit. These results provide evidence that OCT allows more accurate assessment of sub-clinical spread of BCC than clinical observation alone. Such a capability may have clinical value in reducing the number of surgical stages in MMS for BCC. There may also be a role for OCT in aiding the selection of patients most suitable for MMS.

Dermatofibrosarcoma protuberans: 35 patients treated with Mohs micrographic surgery using paraffin sections

BACKGROUND

Dermatofibrosarcoma protuberans (DFSP) has conventionally been treated with wide local excision. More recently Mohs micrographic surgery (MMS) has been advocated.

OBJECTIVES

To assess our departmental experience with DFSP in the context of a literature review relating to DFSP treated with MMS.

METHODS

This was a case review of 35 patients with DFSP treated between 1998 and 2009 with MMS using paraffin-embedded sections.

RESULTS

Seventeen patients required one horizontal layer to clear their tumour, 10 patients needed two and eight patients needed three layers or more. The median preoperative clinical size was 6 cm(2) (range 0·75-54·8) and the median postoperative wound size was 46·8 cm(2) (range 4-145·2). Tumour persistence has not been observed in any of our patients after a median follow-up duration of 29·5 months (range 6-146).

CONCLUSIONS

We present 35 DFSP patients, none of whom showed persistent tumour after treatment with 'slow' MMS using paraffin sections. We advocate MMS as the treatment of choice for DFSP, especially for tumours over the head and neck region where tissue conservation is particularly important.