Long-term deaths from melanoma according to tumor thickness at diagnosis

There is little long-term follow-up information about how the number of melanoma deaths and case fatality vary over time according to the measured thickness of melanoma at diagnosis. This population-based longitudinal cohort study examines patterns and trends in case fatality among 44,531 people in Queensland (Australia) diagnosed with a single invasive melanoma (International Classification of Diseases for Oncology, third revision [ICD-O-3], C44, Morphology 872–879) between 1987 and 2011, including 11,883 diagnosed between 1987 and 1996, with up to 20 years follow-up (to December 2016). The 20-year case fatality increased by thickness, with the percentage of melanoma deaths within 20 years of diagnosis being up to 4.8% for melanomas with measured thickness <0.80 mm, 10.6% for tumors 0.8 to <1.0 mm and generally more than 30% for melanomas measuring 3 mm and more. For melanomas <1.0 mm, most deaths occurred between 5 and 20 years after diagnosis, whereas for thicker melanomas the reverse was true with most deaths occurring within the first 5 years. Five-year case fatality decreased over successive calendar time periods for melanomas <1.0 mm, but not for melanomas ≥1.0 mm. These findings demonstrate that the time course for fatal melanomas varies markedly according to tumor thickness at diagnosis. Improved understanding of the patient factors and characteristics of melanomas, in addition to tumor thickness, which increase the likelihood of progression, is needed to guide clinical diagnosis, communication with patients and ongoing surveillance pathways of patients with potentially fatal lesions.     

Proliferating pilomatricoma

We report on 9 patients with pilomatricomas that showed unusual histopathologic features. Our patients were mainly elderly individuals (age range 42 to 88 years; mean age 70.1 years) who presented solitary cutaneous nodules situated on the head and neck (7 neoplasms), upper arm (1 neoplasm), and back (1 neoplasm). All the lesions were treated by simple excision. Follow-up data available in 7 of the 9 patients (mean follow-up, 17 months) revealed local recurrences in 1 patient whose lesion recurred 3 times. No lymph node involvement or distant metastases were recorded in any of our cases. Histopathologically, most neoplasms were characterized by a relatively large lesion in the clermis that in some cases showed extension to the subcutis. Each lesion was predominantly composed of a lobular proliferation of basaloid cells in association with adjacent focal areas containing eosinophilic, cornified material with shadow cells. In some cases, relatively large areas of shadow cells were present, whereas, in others only small foci of shadows cells were observed. Cytomorphologically, the basaloid cells showed features of matrical and supramatrical cells of a normal hair follicle and exhibited variable nuclear atypia and mitotic figures. The overall architectural pattern of the neoplasms was different from that of large fully developed stereotypical pilomatricomas that maintain a cystic character with basaloid cells predominantly aligned at the periphery. Based on the histopathologic findings, namely the presence of a large, lobular proliferation of basaloid cells in association with small to large foci of shadow cells, we interpreted these neoplasms to be a distinctive proliferative variant of pilomatricoma and propose the designation "proliferating pilomatricoma." Proliferating pilomatricomas should be differentiated from the recently described matricoma, basal-cell carcinoma with matrical differentiation, and matrical carcinoma (pilomatrical carcinoma).     

Traumatic isthmic ruptures of the aorta during the acute phase. Reevaluation of surgical treatment. Thoughts apropos of 47 cases]

From 1976 to 1989, 47 patients with traumatic aortic rupture in the area of the isthmus were seen in our institution; 4 patients died from exsanguination before definitive repair. Forty-three patients were operated on. Most of them (n: 41) underwent repair using partial bypass with pump oxygenator. There were 3 postoperative deaths. No patient developed postoperative paraplegia; 2 patients presented totally regressive spinal disturbances 5 and 8 days after surgery. Two of the 38 survivors were lost to follow-up. Postoperative angiography revealed an excellent aortic result in all cases especially in young patients, except two (1 stenosis, 1 aneurysm). Our experience and a review of the literature indicate some observations: despite rapid transport and evaluation, some patients died from exsanguination before definite repair. Cardiopulmonary bypass and correction of metabolic disturbances may decrease the probability of paraplegia and heparinisation did not increase the risk when orthopedic or abdominal lesions were treated before aortic lesion. Direct repair is recommended as the procedure of choice, especially in young patients, angiographic controls showed excellent results and long term follow-up is very satisfactory.     

Muco-cutaneous colonization and nosocomial infections caused by methicillin-resistant Staphylococcus aureus and Acinetobacter baumanii in intensive care patients

This study was designed to assess the frequency and risk factors for colonization with MRSA and A. baumanii in the intensive care unit, and to analyse the relationship between colonization and infection with MRSA or A. baumanii. During a 24-day survey period, colonization was studied weekly with nasal, throat and digit skin swabs; nosocomial infections were routinely monitored according to CDC recommendations. Clinical data and invasive procedures were registered during a one-year non-epidemic period; 103 ICU patients hospitalized for more than 7 days were prospectively included. We investigated acquired colonization and nosocomial infection with SAMR or A. baumanii for 87 patients not colonized by SAMR or A. baumanii on admission. The colonization acquisition rate was 56% for MRSA and 27% for A. baumanii. Infection incidence (cases per 1,000 patient-days) was 6.46 for MRSA and 1.61 for A. baumanii. On univariate analysis, acquired MRSA colonization was associated with longer ICU stays, longer mechanical ventilation and longer central venous catheterization. Multivariate analysis only showed an association with longer ICU stay. Acquired A. baumanii colonization was associated with SAPSII, longer mechanical ventilation, and longer central venous catheterization in univariate analysis. Multivariate analysis only showed an association with SAPSII and longer mechanical ventilation. In this study, SAMR or A. baumanii infections were not associated with colonization or clinical setting or invasive procedures.     

Gene conversion is a likely cause of mutation in PKD1

Approximately 70% of the gene responsible for the most common form of autosomal dominant polycystic kidney disease ( PKD1 ) is replicated in several highly homologous copies located more proximally on chromosome 16. We recently have described a novel technique for mutation detection in the duplicated region of PKD1 that circumvents the difficulties posed by these homologs. We have used this method to identify two patients with a nearly identical cluster of base pair substitutions in exon 23. Since pseudogenes are known to be reservoirs for mutation via gene conversion events for a number of other diseases, we decided to test whether these sequence differences in PKD1 could have arisen as a result of this mechanism. Using changes in restriction digest patterns, we were able to show that these sequence substitutions are also present in N23HA, a rodent-human somatic cell hybrid that contains only the PKD1 homologs. Moreover, these changes were also detected in total DNA from several affected and unaffected individuals that did not harbor this mutation in their PKD1 gene copy. This is the first example of gene conversion in PKD1 , and our findings highlight the importance of using gene-specific reagents in defining PKD1 mutations.