TINF2 is a major susceptibility gene in Danish patients with multiple primary melanoma

TINF2 encodes the TINF2 protein, which is a subunit in the shelterin complex critical for telomere regulation. Three recent studies have associated six truncating germline variants in TINF2 that have previously been associated with a cancer predisposition syndrome (CPS) caused by elongation of the telomeres. This has added TINF2 to the long telomere syndrome genes, together with other telomere maintenance genes such as ACD, POT1, TERF2IP, and TERT. We report a clinical study of 102 Danish patients with multiple primary melanoma (MPM) in which a germline truncating variant in TINF2 (p.(Arg265Ter)) was identified in four unrelated participants. The telomere lengths of three variant carriers were >90% percentile. In a routine diagnostic setting, the variant was identified in two more families, including an additional MPM patient and monozygotic twins with thyroid cancer and other cancer types. A total of 10 individuals from six independent families were confirmed carriers, all with cancer history, predominantly melanoma. Our findings suggest a major role of TINF2 in Danish patients with MPM. In addition to melanoma, other cancers in the six families include thyroid, renal, breast, and sarcoma, supporting a CPS in which melanoma, thyroid cancer, and sarcoma predominate. Further studies are needed to establish the full spectrum of associated cancer types and characterize lifetime cancer risk in carriers.

An Extensive Case of Merkel Cell Carcinoma due to Fright of COVID-19

Merkel cell carcinoma (MCC) is a subtype of nonmelanoma skin cancer (NMSC) with increasing incidence. Clinically, MCC resembles other far less-aggressive NMSCs, and the pathogenesis is still not understood completely. Rapid diagnosis and treatment are essential to improve overall survival. We present a case report of a 74-year-old female, who had noticed a rapidly growing, oozing tumor on her right flank. She was hesitant to contact the dermatology ward where she had regular checkups as she was afraid of contracting COVID-19. This was in the beginning of the COVID-19 pandemic. At presentation, she had a large exophytic MCC on her right flank and multiple metastases. The disease was at a late stage, and palliative care was the only treatment option left. With this case, we wish to report a rather uncharacteristic location and size of an MCC tumor and suggest that fear of the pandemic and the COVID-19 lockdown has impacted dramatically on attendance of symptomatic patients.

Estimation of the diagnostic accuracy of real-time reverse transcription quantitative polymerase chain reaction for SARS-CoV-2 using re-analysis of published data

INTRODUCTION

As the coronavirus disease 2019 (COVID-19) epidemic evolves and test strategies change, understanding the concepts of testing (gold standard and test performance measures) becomes essential. The challenge of any novel disease is that the gold standard has yet to be defined.

METHODS

We reanalysed published data on real-time reverse transcription quantitative polymerase chain reaction (RT-qPCR) of severe acute respiratory syndrome coronavirus-2 to illustrate how predictive values vary with disease prevalence, sensitivity (set to values between 30% and 95%) and specificity (set to 99% or 99.98%). We used published data on chest CT and RT-qPCR to examine the potential of latent class analysis to estimate the sensitivity and specificity of RT-qPCR when no single gold standard exists.

RESULTS

For the various sensitivity values, the negative predictive value of a RT-qPCR test remained above 92% until a COVID-19 prevalence of > 10%. The positive predictive value (PPV) was more variable. For a sensitivity of 95% and a specificity of 99%, the PPV was less-than 10% at a prevalence of 0.1%, increasing to about 90% at a prevalence of 10%. This improved to a PPV of 85% and almost 100%, respectively, when specificity increased to 99.98%. In a restricted latent class analysis, the sensitivity was 97.1% and the specificity was 99.9%, which is similar to figures from the Danish Health Authority. However, derived predictive values depended on model specification.

CONCLUSIONS

A high risk of false-positives should be considered when extending the testing strategy, whereas false-negatives may occur during local outbreaks. This may have consequences for, e.g., containment strategies and research. A confirmatory test (e.g., demonstrating seroconversion or repeated RT-qPCR) may be warranted.

FUNDING

none.

TRIAL REGISTRATION

not relevant.

The Danish Melanoma Database

AIM OF DATABASE

The aim of the database is to monitor and improve the treatment and survival of melanoma patients.

STUDY POPULATION

All Danish patients with cutaneous melanoma and in situ melanomas must be registered in the Danish Melanoma Database (DMD). In 2014, 2,525 patients with invasive melanoma and 780 with in situ tumors were registered. The coverage is currently 93% compared with the Danish Pathology Register.

MAIN VARIABLES

The main variables include demographic, clinical, and pathological characteristics, including Breslow's tumor thickness, ± ulceration, mitoses, and tumor-node-metastasis stage. Information about the date of diagnosis, treatment, type of surgery, including safety margins, results of lymphoscintigraphy in patients for whom this was indicated (tumors > T1a), results of sentinel node biopsy, pathological evaluation hereof, and follow-up information, including recurrence, nature, and treatment hereof is registered. In case of death, the cause and date are included. Currently, all data are entered manually; however, data catchment from the existing registries is planned to be included shortly.

DESCRIPTIVE DATA

The DMD is an old research database, but new as a clinical quality register. The coverage is high, and the performance in the five Danish regions is quite similar due to strong adherence to guidelines provided by the Danish Melanoma Group. The list of monitored indicators is constantly expanding, and annual quality reports are issued. Several important scientific studies are based on DMD data.

CONCLUSION

DMD holds unique detailed information about tumor characteristics, the surgical treatment, and follow-up of Danish melanoma patients. Registration and monitoring is currently expanding to encompass even more clinical parameters to benefit both patient treatment and research.

[Pachydermodactyly : A rare but benign consequence of repetitive movement patterns]

Pachydermodactyly is an acquired swelling of the lateral aspects of the fingers and is thought to be a reactive pattern due to exogenous factors, such as repetitive mechanical friction. We describe the clinical case of a 17-year-old male patient who presented with the typical symptoms of pachydermodactyly.

Structural asymmetry as a dermatoscopic indicator of malignant melanoma--a latent class analysis of sensitivity and classification errors

Asymmetry of pigmented skin lesions is an important indicator of possible malignant melanoma and contributes substantially to the diagnosis of melanoma in the dermatoscopic ABCD rule for melanocytic lesions and other algorithms. However, it may be observer dependent. Dermatoscopic asymmetry cannot be assessed objectively and no golden standard of asymmetry diagnosis exists. The aim of this study was to assess the sensitivity of axis (a-) symmetry using latent class analysis. We analysed ratings from four experts in dermatoscopy of 232 pigmented lesions by latent class analysis (LCA). Possible ratings were 'no asymmetry', 'asymmetry in one axis' and 'asymmetry in two axes'. A subset of melanocytic lesions (blue naevi excluded) was analysed. Based on LCA, the asymmetry of the singular lesion was determined. The sensitivity of 'no asymmetry' was 40-77%, 40-70% for one-axis asymmetry, and 77-92% for two-axes asymmetry. Overestimation of asymmetry was more common than underestimation. Melanomas were significantly more asymmetric than pigmented naevi, atypical naevi and papillomas, but not basal cell cancers. Analysis of the melanocytic subset gave similar results. The median asymmetry of malignant melanomas (1.67, interquartile range 1.81-1.99) was higher than for melanocytic naevi. In conclusion, asymmetry and symmetry are important criteria for diagnosing or excluding malignant melanoma using the dermatoscopic ABCD rule, risk stratification and other diagnostic rules. Using LCA, we minimized observer dependence in the assessment of axis (a-) symmetry. LCA, besides conceptualizing the diagnostic process, enables the assignment of lesions to their true diagnostic class.

Dermatoscopic prediction of melanoma thickness using latent trait analysis and likelihood ratios

Breslow thickness and Clark level can be used to determine surgical procedures for cutaneous malignant melanoma and patient eligibility for experimental adjuvant therapy. Efforts to predict the thickness of melanomas using dermatoscopy have focused on differences between single dermatoscopic findings. The aim of this study was to develop a method for preoperative identification of melanomas of > or = 1 mm Breslow thickness using the entire range of dermatoscopic findings. Sixty-five melanomas were assessed for the presence of 22 dermatoscopic features. Ten dermatoscopic features showed differences in thick and thin melanomas and were selected for further analysis. A latent trait analysis construct implied that a progression in dermatoscopic features was associated with advancement of melanomas. Early melanomas are characterized by a light brown colour, a pigment network and irregularity or heterogeneity. Gray-blue areas, white scar-like areas and an atypical vascular pattern gradually displace these features. Likelihood ratios were determined for these 6 dermatoscopic findings and an algorithm for calculating the probability of thick malignant melanoma was established.

[Zinc deficiency and pellagra in alcohol abuse]

We report two cases of nutritional deficiency with skin symptoms associated with excessive intake of wine and beer, causing respectively pellagra and zinc deficiency. Supplementation with niacin and zinc had a prompt effect on the skin changes. These cases emphasize the importance of keeping nutritional deficiencies in mind in patients with inadequate nutrition and alcohol abuse.

[Sunbathing habits and risk of melanoma]

The increasing frequency of malignant melanoma (MM) is believed mainly to be due to the habit of sunbathing, which has an impact on the skin due to ultraviolet radiation, especially if intermittent and causing sunburn. Frequent use of tanning booths possibly increases the risk of MM but the question has not been settled. Use of sunscreens has a certain prophylactic effect on actinic keratoses, but no documented effect on MM. This does not imply that sunscreens are not advisable, but stresses the importance of correct use of sunscreens together with other sun protective measures. Primary prevention of MM is mainly a question of minimizing the impact of ultraviolet radiation (including tanning booths) on the skin: limit time in the sun, cover up with clothing, and use a sunscreen with a protection factor of at least 15.

[Dermatoscopic diagnosis of cutaneous malignant melanoma. Secondary prophylaxis]

During the last four decades the incidence of malignant melanoma has increased seven fold. Clinically, it is often difficult to distinguish malignant melanoma from a benign naevus. The macroscopic clinical ABCD rule and the Glasgow 7-point checklist are didactically helpful, but inaccurate with many false positive and negative diagnoses. Dermatoscopy performed by a trained physician has increased the diagnostic accuracy to a sensitivity of 89% and specificity of 80% (meta-analysis of 11 studies). The dermatoscopic ABCD rule and the Risk Stratification method (RS) are reviewed.

[Interobserver variation in the Red-Yellow-Black wound classification system]

Communicating wound descriptions between disciplines for treatment and wound care necessitates a simple and unequivocal classification system. The Red-Yellow-Black (RYB) system has been suggested to comply with these demands. The reliability of the RYB-system has, however only been investigated in small studies. The aim of this study was to determine interobserver homogeneity (group Kappa a.m. Schouten) of the RYB-system and further to examine whether interobserver homogeneity was dependent on educational level. One-hundred-and-twenty photo-slides of non-healing ulcers of various etiologies were shown to 21 observers who recorded their assessments in an entry form without discussing their assessments with the other observers. Eighty-nine percent of the possible assessments were completed. Observed agreement for all observers = 0.65; Kappa = 0.47. Kappa-coefficient in subgroup of nurses = 0.49, subgroup of physicians with less than three years of experience with wound treatment = 0.46 and for physicians with more than 10 years of experience with wound healing = 0.48. In conclusion, we demonstrated moderate interobserver agreement for using the RYB-characteristics. The RYB-system is useful for communication about wound care and treatment. However, continuous education and consensus meetings are advisable to increase agreement.

[Interobserver variation in wound assessments]

Agreement in describing a chronic leg ulcer is pivotal in identifying and treating impediments to the healing process. Six nurses and one doctor without special experience with wound healing registered wound related diagnoses for a five month period. On average each patient was seen by three observers yielding 270 registrations. Agreement beyond chance (global kappa) showed poor to moderate agreement. Agreement was best for the yellow or malodorous wound and lowest for cellulitis, hypergranulation and peripheral pulses. This emphasizes the importance of allocating wound treatment to specialist departments with access to paraclinical investigations.