Prediction of melanoma Breslow thickness using deep transfer learning algorithms

BACKGROUND

The distinction between in situ melanoma (MIS) and invasive melanoma is challenging even for expert dermatologists. The use of pretrained convolutional neural networks (CNNs) as ancillary decision systems needs further research.

AIM

To develop, validate and compare three deep transfer learning (DTL) algorithms to predict MIS vs. invasive melanoma and melanoma with a Breslow thickness (BT) of < 0.8 mm vs. ≥ 0.8 mm.

METHODS

A dataset of 1315 dermoscopic images of histopathologically confirmed melanomas was created from Virgen del Rocio University Hospital and open repositories of the International Skin Imaging Collaboration archive and Polesie S et al. (Dermatol Pract Concept 2021; 11:e2021079). The images were labelled as MIS or invasive melanoma and < 0.8 mm or ≥ 0.8 mm of BT. We conducted three trainings, and overall means for receiver operating characteristic (ROC) curves, sensitivity, specificity, positive and negative predictive value, and balanced diagnostic accuracy outcomes were evaluated on the test set with ResNetV2, EfficientNetB6 and InceptionV3. The results of 10 dermatologists were compared with the algorithms. Grad-CAM gradient maps were generated, highlighting relevant areas considered by the CNNs within the images.

RESULTS

EfficientNetB6 achieved the highest diagnostic accuracy for the comparison between MIS vs. invasive melanoma (61%) and BT < 0.8 mm vs. ≥ 0.8 mm (75%). For the BT comparison, ResNetV2 with an area under the ROC curve of 0.76 and InceptionV3 with an area under the ROC curve of 0.75, outperformed the results obtained by the dermatologist group with an area under the ROC curve of 0.70.

CONCLUSION

EfficientNetB6 recorded the best prediction results, outperforming the dermatologists for the comparison of 0.8 mm of BT. DTL could be an ancillary aid to support dermatologists' decisions in the near future.

Dropout Rate in Digital Health Interventions for the Prevention of Skin Cancer: Systematic Review, Meta-analysis, and Metaregression

BACKGROUND

Digital strategies are innovative approaches to the prevention of skin cancer, but the attrition following this kind of intervention needs to be analyzed.

OBJECTIVE

The aim of this paper is to assess the dropouts from studies focused on digital strategies for the prevention of skin cancer.

METHODS

We conducted this systematic review with meta-analyses and metaregression according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statements. Search terms for skin cancer, digital strategies, and prevention were combined to search PubMed, Scopus, Web of Science, CINAHL, and Cochrane Library from inception until July 2022. Randomized clinical trials that reported dropouts of participants and compared digital strategies with other interventions to prevent skin cancer in healthy or disease-free participants were included. Two independent reviewers extracted data for analysis. The Revised Cochrane Collaboration Bias tool was employed. We calculated the pooled dropout rate of participants through a meta-analysis of proportions and examined whether dropout was more or less frequent in digital interventions against comparators via an odds ratio (OR) meta-analysis. Data were pooled using a random-effects model. Subgroup meta-analyses were conducted in a meta-analysis of proportions and OR meta-analysis to assess the dropout events when data were sorted by digital interventions or control comparator. A univariate metaregression based on a random-effects model assessed possible moderators of dropout. Participants' dropout rates as pooled proportions were calculated for all groups combined, and the digital and comparator groups separately. OR>1 indicated higher dropouts for digital-based interventions. Metaregressions were performed for age, sex, length of intervention, and sample size.

RESULTS

A total of 17 studies were included. The overall pooled dropout rate was 9.5% (95% CI 5.0-17.5). The subgroup meta-analysis of proportions revealed a dropout rate of 11.6% for digital strategies (95% CI 6.8-19.0) and 10.0% for comparators (95% CI 5.5-17.7). A trend of higher dropout rates for digital strategies was observed in the overall (OR 1.16, 95% CI 0.98-1.36) and subgroup OR meta-analysis, but no significant differences were found between the groups. None of the covariates moderated the effect size in the univariate metaregression.

CONCLUSIONS

Digital strategies had a higher dropout rate compared to other prevention interventions, but the difference was not significant. Standardization is needed regarding reporting the number of and reasons for dropouts.

TRIAL REGISTRATION

International Prospective Register of Systematic Reviews (PROSPERO) CRD42022329669; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=329669.

Systemic sclerosis mortality trends in Spain from 1980 to 2019: age-period-cohort and Joinpoint analysis

BACKGROUND

Systemic sclerosis (SSc) is an autoimmune chronic rheumatic disease with notable mortality that continues to be a challenge for clinicians today.

OBJECTIVE

To assess changes in mortality trends in the Spanish SSc population between 1980 and 2019, considering the independent effect of sex, age, period and birth cohort.

PATIENTS AND METHODS

SSc death records and mid-year population data were collected from the National Statistics Institute. Age-standardized mortality rates were calculated for the overall population and for each sex and age group. Significant changes in mortality trends were identified by Joinpoint regressions. Similarly, an age-period-cohort (APC) and potential years of life lost (PYLL) analysis were performed to know the burden of SSc.

RESULTS

Age-standardized mortality rates due to SSc increased from 1.87 (95% CI: 1.00; 3.02) per 1,000,000 inhabitants between 1980 and 1984, to 2.47 (95% CI: 1.74; 3.02) per 1,000,000 inhabitants between 2015 and 2019. The relative risk of mortality fell in cohorts born after 1990 in all groups. The PYLL rates registered a gradual rise in both sexes.

CONCLUSIONS

Mortality due to SSc in Spain Spain experienced a rise in overall mortality trend during the 39 years of study evaluated, although the male group showed a progressive drop.

Hidradenitis suppurativa and Down syndrome in a single-centre sample: A cross-sectional study

Down syndrome (DS) has been related to a higher risk of hidradenitis suppurativa (HS). This cross-sectional study assessed DS patients with HS in a Spanish single-centre sample. DS participants presented a lower age of onset, age at diagnosis and time to diagnosis. Also, DS was not associated with the severity of HS measured by baseline IHS₄ .

Novel Non-Invasive Quantification and Imaging of Eumelanin and DHICA Subunit in Skin Lesions by Raman Spectroscopy and MCR Algorithm: Improving Dysplastic Nevi Diagnosis

Malignant melanoma (MM) is the most aggressive form of skin cancer, and around 30% of them may develop from pre-existing dysplastic nevi (DN). Diagnosis of DN is a relevant clinical challenge, as these are intermediate lesions between benign and malignant tumors, and, up to date, few studies have focused on their diagnosis. In this study, the accuracy of Raman spectroscopy (RS) is assessed, together with multivariate analysis (MA), to classify 44 biopsies of MM, DN and compound nevus (CN) tumors. For this, we implement a novel methodology to non-invasively quantify and localize the eumelanin pigment, considered as a tumoral biomarker, by means of RS imaging coupled with the Multivariate Curve Resolution-Alternative Least Squares (MCR-ALS) algorithm. This represents a step forward with respect to the currently established technique for melanin analysis, High-Performance Liquid Chromatography (HPLC), which is invasive and cannot provide information about the spatial distribution of molecules. For the first time, we show that the 5, 6-dihydroxyindole (DHI) to 5,6-dihydroxyindole-2-carboxylic acid (DHICA) ratio is higher in DN than in MM and CN lesions. These differences in chemical composition are used by the Partial Least Squares-Discriminant Analysis (PLS-DA) algorithm to identify DN lesions in an efficient, non-invasive, fast, objective and cost-effective method, with sensitivity and specificity of 100% and 94.1%, respectively.

Primary cutaneous carcinosarcoma: clinical, histological, and immunohistochemical analysis of eight cases

BACKGROUND

Cutaneous carcinosarcoma is a rare biphasic tumor comprising malignant epithelial and heterologous mesenchymal elements. Data on the clinical and histopathologic characteristics of this tumor are scarce. The objective of this study was to describe the clinicopathologic and immunohistochemical features of cutaneous carcinosarcoma.

METHODS

A descriptive retrospective study was conducted in a tertiary care hospital from Spain. We reviewed the records of eight patients with cutaneous carcinosarcoma who were diagnosed from 2009 to 2019.

RESULTS

The mean patient age at diagnosis was 72.13 years (range 44-91 years), and there was a male predilection (6 cases). The most common site of cutaneous carcinosarcoma was the head and neck (5 cases). Carcinosarcomas demonstrated variable histopathological and immunohistochemical features. Follow-up was available for 7-8 patients. There were two cases of local recurrence and one case of metastasis. Two patients died from the tumor during the entire follow-up.

CONCLUSIONS

Although the number of cases in this study was limited, our results provide valuable insight into the clinical, histopathologic, and immunohistochemical characteristics of primary cutaneous carcinosarcoma.

[Primary cutaneous B-cell lymphomas: study of 22 cases]

INTRODUCTION AND OBJECTIVES

Primary cutaneous B-cell lymphoma (CBCL) is a very low prevalence neoplasm and constitutes 25% of all primary cutaneous lymphomas. Our objective was to discover the epidemiological, clinic and histologic characteristics of CBCL in our area.

METHODS

Retrospective descriptive study with patients with histologic diagnosis of CBCL followed up in our department between 2004 and 2015.

RESULTS

Twenty-two patients with CBCL were included; 65% were men and 35% were women. Follicle centre lymphoma was the most common subtype (41%). Only 3 cases presented with node involvement and one with bone marrow invasion. Five recurrences were detected and one patient died because of the CBCL.

DISCUSSION AND CONCLUSIONS

This is one of the first CBCL series in theSpanish population. The incidence, sex, age, subtype distribution, clinical features and immunohistochemical patterns are very similar to those of the other series.

Oral Nadolol for Children with Infantile Hemangiomas and Sleep Disturbances with Oral Propranolol

BACKGROUND/OBJECTIVE

Oral propranolol has been shown to be safe and effective in infants with infantile hemangioma (IH). Side effects such as sleep disturbances have been associated with propranolol. The aim of this study was to evaluate the efficacy and safety of oral nadolol in a small series of patients whose propranolol therapy was discontinued due to sleep disturbances.

METHODS

A retrospective study of patients with IHs who were treated with oral nadolol due to propranolol-related sleep disturbances at a pediatric tertiary care center between July 2008 and March 2013. Clinical response to oral nadolol and disappearance of propranolol-related side effects were analyzed.

RESULTS

A total of 97 patients presenting IH received oral propranolol. Nine patients (9.3%) developed sleep disturbances. Oral propranolol was discontinued in seven patients and switched to oral nadolol, with resolution of these side effects in 5 (71%) of the cases. One patient developed sleep disturbances again after four months of oral nadolol.

LIMITATIONS

The sample size was too small to draw generalizable conclusions and to draw any statistical inference as to the incidence of sleep disturbances with nadolol therapy.

CONCLUSIONS

The use of oral nadolol in the treatment of IH in our series of 7 patients, resolved the propranolol-related sleep disturbances in 5 (71%), while in one patient the symptoms recurred after 4 months of oral nadolol at a dose of 2 mg/kg/day. In most cases, switching beta-blockers did not compromise efficacy, and is recommended when sleep disturbance necessitates discontinuation of beta-blocker therapy of IH.

Disseminated juvenile xanthogranuloma associated with follicular lymphoma in an adult: successful treatment with chemotherapy and rituximab. A review of the literature

Juvenile xanthogranuloma is a non-Langerhans cell histiocytosis that typically affects children, but several cases have been reported in adults, some in connection with hematologic malignancies. We present the case of a 61-year-old woman with multiple xanthogranulomas who developed a follicular lymphoma after 4 years of follow-up. After 6 months of treatment with chemotherapy and rituximab, the cutaneous lesions disappeared and the patient achieved remission from lymphoma. We highlight this case because xanthogranuloma is a rare disorder that is difficult to diagnose in adults and also because this is the first report of an association between xanthogranuloma and follicular lymphoma. Excellent response was achieved with chemotherapy and rituximab. Finally, given the possible association between xanthogranulomas and hematologic diseases, these lesions may be a cutaneous manifestation of an occult malignancy.

[Nelson syndrome: a rare cause of generalized hyperpigmentation of the skin]

Nelson syndrome is a rare cause of generalized mucocutaneous hyperpigmentation. Its clinical manifestations are due to excessive secretion of adrenocorticotropic hormone from a pituitary adenoma, which develops after bilateral therapeutic adrenalectomy. As this operation has fallen into disuse, Nelson syndrome is now extremely rare and difficult to recognize. We present a very severe case of generalized hyperpigmentation due to Nelson syndrome in a 37-year-old woman.