Primary cutaneous lymphoma patients seen at a referral dermatological centre in 1 year: A single-centre observational retrospective cohort study of the diagnoses and staging, comorbidities and associated symptoms, treatment performed and clinical course.

IMPORTANCE: Primary cutaneous lymphomas (PCL) are rare diseases, but the indolent course makes their prevalence high. Although there are many treatment options, no hierarchy is recommended. OBJECTIVE: To identify the burden of PCL and describe clinical-pathologic features; associated comorbidities; analyse treatment approaches in real-life and the parameters associated with the achievement of complete response (CR). DESIGN, SETTING AND PARTICIPANTS: In this study, all the PCL patients (384 patients) consecutively seen at the Dermatologic Clinic of the University of Turin from January 1, 2019 to December 31, 2019, with follow-up updated to December 2020, were included. MAIN OUTCOMES AND MEASURES: Subtype of PCL, demographic data, time elapsed between first lesions and diagnosis, associated symptoms, comorbidities, staging at diagnosis, high-grade transformation, blood involvement, stage progression, therapies used and response were assessed. RESULTS: 247 were cutaneous T-cell lymphomas (CTCL, 64.3%), 137 cutaneous B-cell lymphomas (CBCL, 35.7%) and the most frequent subtype was MF (48.4%). 62.3% of CTCL patients showed at least one comorbidity, mainly cardiovascular (28.7%), 20.2% show other not cutaneous neoplasms. The main approaches were skin-directed therapies (topical steroids 65.6%; phototherapy 50.2%). 39.3% patients achieved a CR during the disease course. Pruritus, the presence of comorbidities and high-grade transformation were factors associated with failure to achieve CR, whereas stage IA of MF was associated with greater achievement of CR. CONCLUSIONS AND RELEVANCE: The Th2 cytokine related development of pruritus could justify increased resistance to treatment, while the presence of associated comorbidities could reduce treatment options as well as treatment compliance.

Tyrosine Kinase Receptor Expression in Canine Liposarcoma.

The expression of tyrosine kinase receptors is attracting major interest in human and veterinary oncological pathology because of their role as targets for adjuvant therapies. Little is known about tyrosine kinase receptor (TKR) expression in canine liposarcoma (LP), a soft tissue sarcoma. The aim of this study was to evaluate the immunohistochemical expression of the TKRs fibroblast growth factor receptor 1 (FGFR1) and platelet-derived growth factor receptor-ß (PDGFRß); their ligands, fibroblast growth factor 2 (FGF2) and platelet-derived growth factor B (PDGFB); and c-kit in canine LP. Immunohistochemical labeling was categorized as high or low expression and compared with the mitotic count and MIB-1-based proliferation index. Fifty canine LPs were examined, classified, and graded. Fourteen cases were classified as well differentiated, 7 as myxoid, 25 as pleomorphic, and 4 as dedifferentiated. Seventeen cases were grade 1, 26 were grade 2, and 7 were grade 3. A high expression of FGF2, FGFR1, PDGFB, and PDGFRß was identified in 62% (31/50), 68% (34/50), 81.6% (40/49), and 70.8% (34/48) of the cases, respectively. c-kit was expressed in 12.5% (6/48) of the cases. Mitotic count negatively correlated with FGF2 ( R = -0.41; P < .01), being lower in cases with high FGF2 expression, and positively correlated with PDGFRß ( R = 0.33; P < .01), being higher in cases with high PDGFRß expression. No other statistically significant correlations were identified. These results suggest that the PDGFRß-mediated pathway may have a role in the progression of canine LP and may thus represent a promising target for adjuvant cancer therapies.