Associated factors and comorbidities in patients with pyoderma gangrenosum in Germany: a retrospective multicentric analysis in 259 patients.

BACKGROUND: Pyoderma gangrenosum (PG) is a rarely diagnosed ulcerative neutrophilic dermatosis with unknown origin that has been poorly characterized in clinical studies so far. Consequently there have been significant discussions about its associated factors and comorbidities. The aim of our multicenter study was to analyze current data from patients in dermatologic wound care centers in Germany in order to describe associated factors and comorbidities in patients with PG. METHODS: Retrospective clinical investigation of patients with PG from dermatologic wound care centers in Germany. RESULTS: We received data from 259 patients with PG from 20 different dermatologic wound care centers in Germany. Of these 142 (54.8%) patients were female, 117 (45.2%) were male; with an age range of 21 to 95 years, and a mean of 58 years. In our patient population we found 45.6% with anemia, 44.8% with endocrine diseases, 12.4% with internal malignancies, 9.3% with chronic inflammatory bowel diseases and 4.3% with elevated creatinine levels. Moreover 25.5% of all patients had a diabetes mellitus with some aspects of potential association with the metabolic syndrome. CONCLUSIONS: Our study describes one of the world's largest populations with PG. Beside the well-known association with chronic bowel diseases and neoplasms, a potentially relevant new aspect is an association with endocrine diseases, in particular the metabolic syndrome, thyroid dysfunctions and renal disorders. Our findings represent clinically relevant new aspects. This may help to describe the patients' characteristics and help to understand the underlying pathophysiology in these often misdiagnosed patients.

Sentinel lymph node in Merkel cell carcinoma: to biopsy or not to biopsy?

Sentinel lymph node biopsy (SLNB) is commonly recommended for patients with primary Merkel cell carcinoma (MCC). However, it is critically discussed whether survival rates improve by SLNB in MCC patients in general or in subgroups of higher risk (e.g. with primary tumor size >1 cm). The present study correlates clinical data, histology and lymph node status with follow-up and survival data to see if subgroups can be identified for modification of the current recommendations. The medical records of 47 patients with histologically confirmed MCC treated between 1995 and 2010 at a German dermatosurgery department were reviewed. Nineteen patients with excision of the primary tumor and SLNB were compared to 28 patients with excision of the primary tumor but without SLNB. End-points of this study were disease-free survival (DFS) and overall survival (OS). In addition, clinical course was correlated with tumor size and size of safety margin. The group of patients who received SLNB showed a significant advantage in terms of OS (P < 0.05), but not in terms of DFS. Tumors of smaller size were associated with a significantly better DFS and a trend towards better OS. Comparing the groups with different safety margins (1-3 cm), no differences in DFS and OS could be found. Our data support the current recommendation for SLNB in all MCC patients and question the use of extensive safety margins in MCC surgery. Larger prospective multicenter studies with multivariate analysis are needed to confirm whether a prolonged OS is really due to the SLNB procedure or biased by other factors.