Childhood Cutaneous Mastocytosis: Revisited

Cutaneous mastocytosis is a neoplasm characterized by the proliferation and accumulation of mast cells in the skin. There can be involvement of other organ systems as well. Cutaneous manifestations can vary from mastocytoma to maculopapular lesions to diffuse cutaneous form. There can be symptoms associated with mast cell mediators release like itching, flushing, hypotension, diarrhoea, abdominal pain, and anaphylaxis. Hence, the mainstay of treatment is avoidance of triggers causing these mediators to release, anti-histamines, topical/intra-lesional/systemic steroids, mast cell-targeted therapy, epinephrine, and omalizumab depending upon the severity of symptoms/signs. Childhood cases usually have a good prognosis except in a few cases, especially those with systemic involvement. Such situations might warrant cytoreductive therapy, polychemotherapy, or autologous stem cell transplantation. Here, we intend to review the English literature on childhood cutaneous mastocytosis.

Polymyalgia rheumatica-like presentation in a case of diffuse large B-cell lymphoma: a diagnostic pitfall

Diffuse large B-cell lymphoma (DLBCL) commonly presents with systemic manifestations including fever, weight loss, and night sweats. Uncommonly, patients with DLBCL can present with musculoskeletal manifestations mimicking polymyalgia rheumatica (PMR). Herein, the case of a 61-year-old woman who presented with pain in the bilateral shoulders, arms, hands, knees, pelvic girdle, and neck with bouts of fever, is presented. Laboratory workup for infectious and connective tissue diseases was non-revealing, except for elevated inflammatory markers. A positron emission tomography (PET)/computed tomography (CT) scan was suggestive of PMR, but also revealed enlarged lymph nodes initially thought to be reactive in nature. However, a lymph node biopsy showed findings consistent with DLBCL. This case highlights the importance of a thorough investigational workup when cases with features of PMR do not meet the proper criteria for this diagnosis to be made, in order not to miss a hematopoietic neoplasm with a PMR-like presentation.

Screening for dental focal infections in febrile patients with hematologic malignancies who received chemotherapy: a retrospective cohort study

Source of fever in chemotherapy patients is often unknown. Fever can also be fatal. No observational studies have determined the incidence of dental focal infection (DFI)-associated fever, despite oral cavity being a potential source of infection. We report the incidence of fever after chemotherapy in patients with hematological malignancies and their association with DFIs in 441 patients visiting our institution during a 6-year period. Dental treatments, including tooth extraction, were performed, and their oral and hematological profiles were monitored after chemotherapy. Fever was evident in 87 (38.5%) of 226 patients (≥ 38˚C) after the first cycle of chemotherapy. Sepsis due to DFIs (n = 4; 4.6%) was evaluated. Chemotherapy was delayed due to DFI in one case. Fever after chemotherapy should be differentiated from oral infections. Our study emphasizes the significance of DFI in patients with fever after chemotherapy and can help in improving the prognosis of patients.

Spinal extradural T-cell lymphoma with paraneoplastic hypereosinophilia in a dog: clinicopathological features, treatment, and outcome

Spinal lymphoma is a rare manifestation of a common canine hematopoietic neoplasia. Description of treatment, outcome, and MRI features are scarce. The latter can be heterogeneous, stressing the importance of lesion excision and analysis. Clinicians should also be aware of hypereosinophilia as accompanying paraneoplastic syndrome and its potential prognostic implications.

Metabolic Abnormalities Detected in Phase II Evaluation of Doxycycline in Dogs with Multicentric B-Cell Lymphoma

Doxycycline has antiproliferative effects in human lymphoma cells and in murine xenografts. We hypothesized that doxycycline would decrease canine lymphoma cell viability and prospectively evaluated its clinical tolerability in client-owned dogs with spontaneous, nodal, multicentric, substage a, B-cell lymphoma, not previously treated with chemotherapy. Treatment duration ranged from 1 to 8 weeks (median and mean, 3 weeks). Dogs were treated with either 10 (n = 6) or 7.5 (n = 7) mg/kg by mouth twice daily. One dog had a stable disease for 6 weeks. No complete or partial tumor responses were observed. Five dogs developed grade 3 and/or 4 metabolic abnormalities suggestive of hepatopathy with elevations in bilirubin, ALT, ALP, and/or AST. To evaluate the absorption of oral doxycycline in our study population, serum concentrations in 10 treated dogs were determined using liquid chromatography tandem mass spectrometry. Serum levels were variable and ranged from 3.6 to 16.6 µg/ml (median, 7.6 µg/ml; mean, 8.8 µg/ml). To evaluate the effect of doxycycline on canine lymphoma cell viability in vitro, trypan blue exclusion assay was performed on canine B-cell lymphoma cell lines (17-71 and CLBL) and primary B-cell lymphoma cells from the nodal tissue of four dogs. A doxycycline concentration of 6 µg/ml decreased canine lymphoma cell viability by 80%, compared to matched, untreated, control cells (mixed model analysis, p < 0.0001; Wilcoxon signed rank test, p = 0.0313). Although the short-term administration of oral doxycycline is not associated with the remission of canine lymphoma, combination therapy may be worthwhile if future research determines that doxycycline can alter cell survival pathways in canine lymphoma cells. Due to the potential for metabolic abnormalities, close monitoring is recommended with the use of this drug in tumor-bearing dogs. Additional research is needed to assess the tolerability of chronic doxycycline therapy.