Systemic mastocytosis: A cohort study on clinical characteristics of 136 patients in a large tertiary centre.

BACKGROUND: Systemic mastocytosis (SM) is a rare heterogeneous disease which is characterized by the aberrant proliferation of mast cells. It can be divided into various subtypes with different phenotypes and prognoses. Here, we report on the clinical characteristics of 136 SM patients. METHODS: A retrospective cohort study was conducted from January 2009 to September 2014 in a large tertiary centre in The Netherlands. We included all patients who fulfilled WHO criteria for SM. Data were collected from electronic patient files. RESULTS: A total of 124 patients had indolent SM (ISM) (91.2%), 7 had aggressive SM (ASM) (5.1%) and 5 had SM with associated hematological non-mast cell lineage disease (SM-AHNMD) (3.7%). There was no progression from ISM to advanced SM subtypes, but 1 patient with ASM developed chronic myelocytic leukemia 2years after diagnosis. The average time to diagnosis for the whole population was 8.1years (range, 0-49years). The most frequent triggers for work-up-skin involvement, anaphylaxis and osteoporosis-were characterized by an interval to diagnosis of 10.9, 2.9 and 7.5years, respectively. A total of 32 patients (23.5%) had a serum tryptase levels below the cutoff value of 20ng/mL at the time of diagnosis, but these patients did not have significant differences in clinical phenotype. CONCLUSIONS: SM comprises a wide spectrum of signs and symptoms and its often atypical presentation can delay the establishment of the diagnosis substantially. Skin involvement, anaphylaxis and unexplained osteoporosis should trigger analysis for mastocytosis. A normal serum tryptase does not exclude the diagnosis of SM.

Cutaneous squamous cell carcinoma with perineural invasion: report on eight cases and review of the literature.

BACKGROUND: Perineural invasion (PNI) in cutaneous squamous cell carcinoma (SCC) is considered to be a negative prognostic factor. A lot of uncertainty remains regarding the classification, diagnosis, treatment and prognosis of SCC with PNI. OBJECTIVE: To describe typical courses of SCC with PNI and associated findings in order to suggest an optimized diagnostic and therapeutic approach. METHODS: We present eight cases of SCC with PNI, considering patient and tumor characteristics, histology, treatment and clinical course regarding local recurrence and metastasization. RESULTS: SCC patients with PNI have a higher rate of local recurrences and greater risk for metastasization than SCC patients without PNI. Age ranged from 68 to 77 years, 6 patients were male and 2 female, with all tumors localized on the head. Three patients had chronic lymphocytic leukemia. CONCLUSION: Based on the data of this series and the current literature, we make suggestions for better diagnostic and therapeutic management.