Transcriptomic analyses reveal three distinct molecular subgroups of Merkel cell carcinoma with differing prognoses.

Merkel cell carcinoma (MCC) is a cutaneous neuroendocrine malignancy with a poor prognosis and an unknown cell of origin. Proffered cells of origin include epithelial stem cells of the hair follicle or interfollicular epidermis, dermal stem cells and pro/pre- or pre-B cells. MCC has also been proposed to have more than one cell of origin and indeed to represent more than one type of carcinoma, currently grouped together due to phenotypic similarities. We explored the heterogeneous nature of MCC by studying the most variably expressed genes with the goal of identifying gene expression patterns that are either clinically relevant or have implications regarding the cell(s) of origin. We performed RNA sequencing on primary tumor samples from 102 patients and identified the top 200 most variably expressed genes. These genes and the tumor samples were hierarchically clustered based on their expression. The functions of three gene clusters exhibiting clearly divergent expression between samples were studied by cross-referencing the lists of genes with online databases. High expression of a gene cluster related to embryonic developmental processes and low expression of a gene cluster related to neuroendocrine processes distinguished Merkel cell polyomavirus (MCPyV)-negative tumors from MCPyV-positive tumors. Furthermore, two prognostically relevant subgroups of MCPyV-positive MCC were identified based on dichotomic expression of genes related to epidermal structures and processes. We identified three distinct molecular subgroups of MCC with prognostic relevance. We propose that the dichotomic expression of epidermis-related genes might reflect both an epidermal and a nonepidermal origin for MCPyV-positive MCC.

Hot dots - which nodes should be removed in sentinel lymph node biopsy for melanoma?

BACKGROUND: Sentinel lymph node biopsy (SLNB) is a critical staging tool for melanoma patients. The optimal number of lymph nodes removed in SLNB remains unclear. In this study, we retrospectively analysed and tested different criteria for selecting sentinel lymph nodes (SLNs) by radiotracer uptake and blue dye, and their impact on nodal staging. We also evaluated the association between SLN tumour burden and radiotracer uptake. METHODS: The study population consisted of melanoma patients undergoing SLNB. During the operation all radioactive and blue nodes were removed and sent for histopathological analysis. The ex vivo radioactive count and presence of blue dye of each node were recorded, and these were correlated with presence and size of metastasis in each SLN. RESULTS: Altogether 175 patients with clinically occult metastasis presented with one or more positive, i.e. metastatic, SLNs. The mean number of lymph nodes removed was 4.5, and the mean number of positive lymph nodes was 1.5 per patient. The most radioactive or hottest node was negative in 38 patients (22%). By removing the hottest node and all nodes with radioactivity >10% of the hottest node, 97% of patients would have been staged correctly. In five patients, metastasis was found solely in a SLN with radioactivity <10% of the hottest node. Of all 267 positive nodes removed, 125 (47%) contained blue dye. Patients with a negative hottest node were associated with lower SLN tumour burden. CONCLUSIONS: By removing the hottest node and all nodes with radioactivity >10% of the hottest node, 97% of patients with SLN metastases are correctly staged with or without using blue dye.

Eccrine Porocarcinoma: Clinical and Histopathological Study of 14 Patients with Special Emphasis on Sentinel Lymph Node Biopsy.

Eccrine porocarcinoma is a rare skin adnexal tumour that affects elderly people. Most eccrine porocarcinomas are stage I or II according to the American Joint Committee on Cancer. The prognosis is good in early stages, but worsens when advanced. Since information on the use of sentinel lymph node biopsy in these patients is scarce, this study examined the records of all patients with eccrine porocarcinoma treated at Helsinki University Hospital during a 17-year period and focused on sentinel lymph node biopsy patients. The study identified 14 patients (9 male, 5 female). There were 2 metastases to the lymph nodes and 2 recurrences at initial referral to our institution. All primary tumours had wide local excision and 6 patients also had sentinel lymph node biopsy, of whom none had positive lymph nodes. There were no new metastases or recurrences during follow-up. Three patients died of causes other than eccrine porocarcinoma. When comparing the wide local excision only and wide local excision with sentinel lymph node biopsy groups, no parameters reached statistical significance. The decision process of the multidisciplinary tumour board meeting on whether to perform sentinel lymph node biopsy was not clear, perhaps due to the limited knowledge of eccrine porocarcinoma. Further studies and international collaboration are warranted.

Kajava Classification: The Person and the Research.

The Kajava classification for ectopic breast tissue is still widely used, although it was published in 1915 in Finnish. This historical note sheds light on the person and research behind the classification. Level of Evidence V This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Bumping to a rollator walker: How pretibial hematomas create more costs than pretibial lacerations.

Pretibial lacerations (PL) and pretibial hematomas (PH) are debilitating traumas among the elderly and infirm. The injuries are frequently grouped together despite differences in treatment and symptoms. Patients are known to have multiple contacts in health care, perhaps because of inadequate treatment. Despite the burden, financial costs have not been assessed. Calculate and compare the treatment costs of PLs and PHs for differences and provide economic incentives to treat and diagnose patients optimally. From linkage to ICD10 diagnoses, we analysed NordDRG product invoices generated by the treatment of the patients. We calculated and compared the costs of treatment in both cohorts from the invoices. This method has not been previously used for analysing wound care costs. Mean treatment costs were 1800€ (PL) and 3300€ (PH). The total costs, emergency room, surgical treatment, and inpatient care of PHs were higher than PLs (P = .0486, P = .0002, P = .0058, P = .6526). PLs generate more costs from the outpatient clinic but were not statistically significant (P = .6533). PHs cause a higher economic burden than PLs. Costs arise from repeat ER visits and the need for surgeries because of delayed treatment. PLs have multiple contacts in the wound clinic. Improvement in the diagnosis and treatment of both injuries is needed.

Merkel cell polyomavirus is a passenger virus in both poroma and porocarcinoma.

BACKGROUND: Merkel cell polyomavirus (MCPyV) has been studied in several malignant and nonmalignant tissues. However, only in Merkel cell carcinoma (MCC) has the connection to tumorigenesis been established. Previously, eccrine porocarcinoma samples were shown to express MCPyV in the majority of samples. We aimed to examine MCPyV in porocarcinoma and poroma samples using MCC as the reference material. METHODS: We analyzed 17 porocarcinoma and 50 poroma samples for the presence of MCPyV using LT antigen immunostaining and DNA detection methods. In addition, 180 MCC samples served as controls. RESULTS: MCPyV LT antigen immunostaining was detected in 10% of poroma and 18% of porocarcinoma samples; on the other hand, it was present in 65% of MCC samples. MCPyV DNA was detected in only 10% of poroma and porocarcinoma samples compared with 96% of MCC samples. The viral DNA copy number in all MCPyV DNA-positive MCCs was at least 25 times higher than that in porocarcinoma or poroma samples with the highest MCPyV DNA-to-PTPRG ratio. CONCLUSIONS: The low number of viral DNA copies in poroma and porocarcinoma samples, together with the negative LT expression of MCPyV DNA-positive tumors, indicates that MCPyV is simply a passenger virus rather than an oncogenic driver of porocarcinoma.

The Merkel Cell Polyomavirus T-Antigens and IL-33/ST2-IL1RAcP Axis: Possible Role in Merkel Cell Carcinoma.

Merkel cell polyomavirus (MCPyV) is a causal factor in Merkel cell carcinoma (MCC). The oncogenic potential is mediated through its viral oncoproteins large T-antigen (LT) and small T-antigen (sT). Cytokines produced by tumor cells play an important role in cancer pathogenesis, and viruses affect their expression. Therefore, we compared human cytokine and receptor transcript levels in virus positive (V+) and virus negative (V-) MCC cell lines. Increased expression of IL-33, a potent modulator of tumor microenvironment, was observed in V+ MCC cell lines when compared to V- MCC-13 cells. Transient transfection studies with luciferase reporter plasmids demonstrated that LT and sT stimulated IL-33, ST2/IL1RL1 and IL1RAcP promoter activity. The induction of IL-33 expression was confirmed by transfecting MCC-13 cells with MCPyV LT. Furthermore, recombinant human cytokine domain IL-33 induced activation of MAP kinase and NF-κB pathways, which could be blocked by a ST2 receptor antibody. Immunohistochemical analysis demonstrated a significantly stronger IL-33, ST2, and IL1RAcP expression in MCC tissues compared to normal skin. Of interest, significantly higher IL-33 and IL1RAcP protein levels were observed in MCC patient plasma compared to plasma from healthy controls. Previous studies have demonstrated the implication of the IL-33/STL2 pathway in cancer. Because our results revealed a T-antigens-dependent induction of the IL-33/ST2 axis, IL-33/ST2 may play a role in the tumorigenesis of MCPyV-positive MCC. Therefore, neutralizing the IL-33/ST2 axis may present a novel therapeutic approach for MCC patients.

Malignant Eccrine Porocarcinoma in Finland During 2007 to 2017.

Malignant eccrine porocarcinoma is a rare skin adnexal cancer arising from the sweat glands. Little is known about the epidemiology and incidence of eccrine porocarcinoma. This registry-based study examined the epidemiology and incidence data for eccrine porocarcinoma from the Finnish Cancer Registry. The study included all persons diagnosed with eccrine porocarcinoma in 2007 to 2017. There were 69 cases in the study period; 34 (49%) male and 35 (51%) female patients. Mean age at diagnosis was 75.5 years. Incidence for men was 0.06 per 100,000 person-years and for women 0.04 per 100,000 person-years adjusted for age according to the World Standard Population. Incidence increased with age. There was one eccrine porocarcinoma-specific death among the 69 patients. The incidence of eccrine porocarcinoma in Finland is therefore low. The mean age at time of diagnosis and the location of eccrine porocarcinoma are consistent with previous reports. The survival of patients with eccrine porocarcinoma is high.

ALK and EGFR expression by immunohistochemistry are associated with Merkel cell polyomavirus status in Merkel cell carcinoma.

AIMS: Merkel cell carcinoma, a rare cutaneous neuroendocrine tumour of the skin, can be categorised into two groups according to Merkel cell polyomavirus (MCV) presence. MCV-negative tumours are more aggressive and frequently associated with gene mutations. Some of the genes are potential therapeutic targets. We have previously reported EGFR mutations in six of 27 MCC tumours and overexpression of ALK and EZH2 at mRNA level in MCC tumours. In this study, we sought to determine expression of ALK, EGFR and EZH2 in MCC samples and assess their correlation to MCV status and clinical parameters. METHODS AND RESULTS: Tissue microarrays were utilised and stained with primary antibodies. Staining data were statistically compared to patient sex, tumour location and development of metastasis and MCC-specific death; 112 tumours and their corresponding patient data were included. We found strong expression of ALK in 51% and strong expression of EZH2 in 76% of the tumours. There was evident correlation of ALK expression with MCV-positivity. Expression of EGFR was infrequent, presenting only in seven MCV-negative tumours. None of the proteins associated with development of metastasis or MCC specific death. CONCLUSIONS: ALK and EZH2 expression are frequent in MCC and ALK expression correlates to MCV positivity. EGFR positive tumours might respond to EGFR inhibiting treatment.

The expression of terminal deoxynucleotidyl transferase and paired box gene 5 in Merkel cell carcinomas and its relation to the presence of Merkel cell polyomavirus DNA.

BACKGROUND: Merkel cell carcinoma (MCC) tumor samples frequently express B-lymphoid lineage markers. However, the reasons for expression of specific B-lymphoid lineage markers are still unclear. We studied the expression of TdT and PAX5 (two B-cell lymphoid lineage markers) in a large pool of MCC tissue microarray samples. METHODS: Immunoexpression and staining intensities of TdT and Pax-5 were statistically correlated with patient, tumor, Merkel cell polyomavirus (MCV), and disease-specific parameters. RESULTS: In a cohort of 117 MCC patients and their corresponding tumor samples, TdT was expressed in 37 (31.6%) samples and PAX5 in 26 (22.2%). Simultaneous immunostaining for TdT and PAX5 was observed in 13 (11.1%) samples. A statistically significant relationship was observed between MCV virus copy number and positive TdT expression (P = 0.0056). Similarly, a significant relationship was also observed between positive TdT and tumor MCV virus positivity (P = 0.000495). CONCLUSION: We observed frequent TdT and PAX5 immunoexpression in MCC tumor samples. However, simultaneous immunoexpression of these markers was scarce. TdT expression was statistically significantly associated with MCV positivity. The absence of a statistically significant association between tumor parameters and disease progression markers undermines the systemic use of these markers in clinical practice.

Additional squamosal suture synostosis and segmented intracranial volume in patients with non-syndromic sagittal synostosis.

PURPOSE: To evaluate the incidence of squamosal suture synostosis (SQS) in children with non-syndromic sagittal synostosis and to evaluate whether the additional SQS affects the intracranial volume (ICV). METHODS: Thirty-four consecutive patients (23 boys) who had been operated by cranial vault remodelling because of sagittal synostosis were compared retrospectively from 3D-CT imaging data sets obtained from volumetric CT. The mean age of the patients at preoperative CT imaging was 0.48 (range 0.13-1.3) years. Mann-Whitney U test was used in the statistical analyses. RESULTS: Sagittal synostosis was combined with SQS in four children (11.7%) but the additional SQS did not affect the ICV. SQS was unilateral in all children, two were located on the right and two on the left side. The length of the SQS varied between 4 and 27 mm. The children with SQS had a shorter sagittal suture synostosis length ratio (length of synostosis / total sagittal suture length × 100) than those without SQS. CONCLUSIONS: The incidence of SQS in non-syndromic sagittal synostosis was 11.7% but SQS did not affect the ICV.

Length of synostosis and segmented intracranial volume correlate with age in patients with non-syndromic sagittal synostosis.

PURPOSE: The aim of this study is to compare the length of synostosis and segmented intracranial volume (SIV) with age in children with non-syndromic sagittal synostosis. METHODS: Thirty-three consecutive patients (22 boys) who had been operated by cranial vault remodeling because of sagittal synostosis were compared retrospectively from 3D-CT imaging data sets obtained from volumetric CT. The mean age of the patients at preoperative CT imaging was 0.49 (range 0.13-1.3) years and at 1-year postoperative imaging 1.8 (range 1.3-3) years. The mean interval between preoperative CT imaging and surgery was 0.25 (range 0-0.8) years. Pearson's correlation and Student's t test were used in the statistical analyses. RESULTS: Length of sagittal synostosis correlated positively with age at preoperative CT (r = 0.688, p < 0.01). Children with total synostosis (n = 9) were significantly older (mean age 0.74 vs. 0.4 years, p < 0.01) than those with partial synostosis. Of partial synostoses, 9 were located anteriorly, 3 in the middle, and 12 posteriorly. The mean synostosis ratio (synostosis length/total sagittal suture length × 100) was 83%. Preoperative SIV correlated positively with age at preoperative CT (r = 0.788, p < 0.01), whereas the 1-year postoperative SIV did not correlate with age at operation. The older the child at the time of the operation, the less the percentage SIV increased. CONCLUSIONS: Length of sagittal synostosis and SIV increased with age.

History of chronic inflammatory disorders increases the risk of Merkel cell carcinoma, but does not correlate with Merkel cell polyomavirus infection.

BACKGROUND: We aimed to assess the connection between chronic inflammatory disorders (CIDs) and Merkel cell carcinoma (MCC). METHODS: Merkel cell carcinoma cases diagnosed in 1978-2009 were extracted from the Finnish Cancer Registry and controls from the Population Registry. Information on reimbursed CIDs was linked to clinicopathological data including Merkel cell polyomavirus (MCV) status by qPCR and immunohistochemistry for the large T antigen of MCV (LTA), Ki-67 and tumour-infiltrating lymphocytes. RESULTS: Chronic inflammatory disorders increased the risk of MCC significantly (odds ratio (OR) 1.39, 95% confidence interval (CI) 1.03-1.88), specifically connective tissue/systemic diseases (OR 1.75, 95% CI 1.09-1.80) and diabetic conditions (OR 1.51, 95% CI 1.03-2.22). Chronic inflammatory disorders associated with larger tumour diameter (P=0.02) and higher Ki-67 expression (P=0.005). The expression of LTA was seen significantly more often in the absence of CIDs (P=0.05). CONCLUSIONS: Patients with CID are at significantly higher risk for aggressive MCC. Merkel cell polyomavirus positivity is more common in MCC patients unafflicted by CID.

Aberrant expression of ALK and EZH2 in Merkel cell carcinoma.

BACKGROUND: Distinct characteristic features categorize Merkel cell carcinoma (MCC) into two subgroups according to the Merkel cell polyomavirus infection. Many mutational studies on MCC have been carried out in recent years without identifying a prominent driver mutation. However, there is paucity reporting the expression of cancer genes at the RNA level in MCC tumors. In this study, we studied the RNA expression profiles of 26 MCC tumors, with a goal to identify prospective molecular targets that could improve the treatment strategies of MCC. METHODS: RNA expression of 50 cancer-related genes in 26 MCC tumors was analyzed by targeted amplicon based next-generation sequencing using the Ion Torrent technology and the expression compared with that of normal, non-cancerous skin samples. Sequencing data were processed using Torrent Suite™ Software. Expression profiles of MCV-negative and MCV-positive tumors were compared. Fluorescence in situ hybridization was performed to study ALK rearrangements and immunohistochemistry to study ALK expression in tumor tissue. RESULTS: ALK, CDKN2A, EZH2 and ERBB4 were overexpressed, and EGFR, ERBB2, PDGFRA and FGFR1 were underexpressed in MCC tumors compared to normal skin. In the MCV-negative tumors, MET, NOTCH1, FGFR3, and SMO were overexpressed and JAK3 and NPM1 were under-expressed compared to the MCV-positive tumors. CONCLUSIONS: High expression of ALK, CDKN2A and EZH2 was recorded in MCC tumors. No ALK fusion was seen by FISH analysis. Overexpression of EZH2 suggests its potential as a drug target in MCC.

Post-transplant Merkel Cell Carcinoma.

Malignant tumours are the foremost complications of immunosuppressive treatment. They are a major challenge for organ transplant recipients and their treating physicians. This paper reviews the aetiology and current treatment of an unusual neuroendocrine skin cancer, Merkel cell carcinoma (MCC), caused by a Merkel cell polyomavirus infection. MCC occurs more frequently than expected in immunosuppressed subjects, especially in organ transplant recipients. The current literature comprises reports of 79 organ transplant recipients with MCC. The risk of MCC in organ transplant recipients is increased up to 66-182-fold compared with the general population. In addition to the increased risk of developing MCC, immunosuppressed individuals have poorer MCC-specific survival. The aim of this review article is to familiarize organ transplant doctors with this unique and clinically challenging skin cancer, and to provide recent data on the diagnosis and current treatment recommendations for an immunosuppressed population.

Prehospital Care of Burn Patients and Trajectories on Survival.

We sought to identify factors associated with the prognosis and survival of burn patients by analyzing data related to the prehospital treatment of burn patients transferred directly to the burn unit from the accident site. We also aimed to assess the role of prehospital physicians and paramedics providing care to major burn patients. This study included adult burn patients with severe burns treated between 2006 and 2010. Prehospital patient records and clinical data collected during treatment were analyzed, and the Injury Severity Scale (ISS) was calculated. Patients were grouped into two cohorts based on the presence or absence of a physician during the prehospital phase. Data were analyzed with reference to survival by multivariable regression model. Specific inclusion criteria resulted in a sample of 67 patients. The groups were comparable with regard to age, gender, and injury etiology. Patients treated by prehospital physicians (group 1, n = 49) were more severely injured than patients treated by paramedics (group 2, n = 18) in terms of total burn surface area (%TBSA) (32% vs. 17%, p = 0.033), ISS (25 vs. 8, p < 0.000), and inhalation injuries (51% vs. 16%, p = 0.013), and presented with a higher pulse rate, lower systolic blood pressure, and lower median pH. Age, gender, %TBSA, and ISS were significantly associated with survival in both groups. Survival at 30 days was associated with age, gender, the amount of intravenous fluids (in liters) received during the first 24 hours, and the final %TBSA. Variables found to be independently associated by multivariable regression model with 30 day mortality were age, female gender, and final TBSA. We identified prehospital prognostic factors affecting patient outcomes. Based on the results from this study, our current EMS system is capable of identifying seriously injured burn patients who may benefit from physician attendance at the injury scene.

[Dangerous animals]. / Vaaralliset eläimet.

Contacts between humans and animals inevitably involve encounters possibly resulting in the human being injured. During the period of 2000 to 2014 almost 90 people died in this kind of conflict in Finland. Of these deaths, one third were associated with horses. In addition, over the same period 85 people died in traffic accidents in which an animal was hit by a car. Accidents requiring hospitalization occurred for approx. 8 000 people.

Mechanical Analysis of Ultrasound-Activated Pins and Resorbable Screws: Two Different Techniques to Fixate Osteosynthesis in Craniosynostosis Surgery.

PURPOSE: Ultrasound activation of resorbable pins directly into drilled holes of the calvarium was introduced to overcome the time-consuming installation in the resorbable osteosynthesis fixation in craniosynostosis surgery. There is paucity in the data comparing the mechanical properties of resorbable screws and ultrasound-activated pins produced by different manufacturers. The aim of this experimental study was to compare the mechanical properties of ultrasound-activated pins and resorbable screws. METHODS: A mechanical testing machine was used to characterize the mechanical performance of screws and ultrasound pins. The screws and pins were tested individually in 2 directions with respect to the longitudinal axis: vertical, that is, axial pull-out strength and horizontal, that is, shear strength. The mean maximum strength of fixation was determined. Broken screws and pinheads were analyzed by a scanning electron microscope to determine the site of fracture. RESULTS: All of the resorbable screws and pins broke at the point where the device enters bone. In pull-out testing, the mean maximum strength of the ultrasound-activated pins was 30.5 ± 5.4 N and that of the resorbable screws was 54.0 ± 0.3 N. In shear testing, the mean maximum strength of ultrasound-activated pins was 57.1 ± 20.1 N and that of the resorbable screws was 53.9 ± 0.4 N. CONCLUSIONS: In their intended configuration, there is no clinically significant difference in fixation strength between ultrasound-activated pins and resorbable screws.

Cephalic index correlates poorly with intracranial volume in non-syndromic scaphocephalic patients.

OBJECTIVES: This study aims to compare pre- and postoperative cephalic indexes (CI) with corresponding segmented intracranial volumes (SIV) obtained from volumetric CT in scaphocephalic patients. METHODS: Twenty-four patients (17 boys) who had undergone cranial vault remodeling due to scaphocephaly were compared from 3D-CT imaging datasets. The mean age of the patients at preoperative CT imaging was 5.5 months, and that at 1-year postoperative imaging, 21.5 months. The mean interval between preoperative CT imaging and surgery was 3.3 months. Pearson's correlation was used to test the correlation of both pre- and postoperative CI with SIV. A paired t test was used to compare differences in the pre- and postoperative mean values of CI and SIV. RESULTS AND DISCUSSION: CI correlated poorly with intracranial volume both preoperatively (r = 0.274) and postoperatively (r = 0.128). The mean preoperative CI was 65.92 (range 57.99-73.97), and the mean postoperative, CI 70.24 (range 60.23-75.57). The mean preoperative intracranial volume was 877.79 cm(3) (range 638-1,256), and the 1-year postoperative volume, 1,249.04 cm(3) (range 1,039-1,529). The mean values of both CI and SIV increased significantly after surgery. In one patient, the CI in postoperative measurements was smaller, whereas in all patients, the postoperative SIV was larger than the preoperative intracranial volume. The mean percentage increase in CI was 6.6 %, whereas the mean increase in SIV was 43.1 %. CONCLUSION: Cephalic index correlates poorly with intracranial volume in non-syndromic scaphocephalic patients. For some patients, surgery and growth resulted in only subtle or no change in CI despite a notable increase in intracranial volume.