Age: 71.0
Sex: F
Vaccine: FLU3, FLUX, FLUX, FLUX, FLUX
Symptoms: Injection site induration, Injection site plaque, Light chain analysis normal, Lymphocytic infiltration, Neoplasm skin
Clinical narrative: Initial unsolicited report received from literature on 7 July 2015. Abstract: Blastic plasmacytoid dendritic cell neoplasms (BPDN) are exceeding rare T-cell neoplasms that carry a dismal prognosis. Today, the exact etiology of the disease is unclear, and to our knowledge, no cases of BPDN have been reported at the site of vaccination injection. Additionally, all currently described cases described have dismal prognosis, and, to our knowledge, there are no reports of such lesions responding to topical steroid treatment. Herein, we present an unusual case of BPDN occurring at an influenza vaccination site that subsequently resolved after high-potency topical steroid treatment. A 71-year-old male patient, with no significant medical history and concomitant medications were not reported, had received a dose of Influenza Vaccine (batch number, route and site of administration were not reported) on unspecified date. On an unspecified date, seven days after vaccination, the patient presented with a 5.0 cm nontender, erythematous, and scaling plaque with an indurated border on the left upper arm. The lesion appeared at the site of an influenza vaccination. The patient denied systemic symptoms and any such reaction with previous vaccinations in the past. A topical high-potency steroid, diflorasone diacetate 0.05 percent, was prescribed and radiation therapy was delivered at the site as corrective treatment. The laboratory investigation was reported as biopsy found an atypical dense lymphoid infiltrate in the papillary and reticular dermis. A grenz zone was present. The infiltrate shows prominent perivascular distribution. The individual lymphocytes had hyperchromatic nuclei with irregular nuclear contour and nucleoli crush artefact was present at the periphery of the biopsy section. Immuno histochemical profiling found the lesion to be diffusely CD4 and CD56. Most of the lesion cells were also CD123 and TdT. Repeat CD123 staining found more intense and diffuse positivity. Admixed were rare CD791 B Cells. Tests for myeloperoxidase, CD34, MUM1, PAX5, CD3, CD10, CD21, kappa, and lambda were negative. Epstein Barr virus in situ hybridization results were also negative. In addition to these markers, an outside hospital found that our lesion was TCL11 and CD117 and muramidase negative. After histologic and immune profiling of CD4, CD56, TCL1, and CD123, a diagnosis of BPDN was rendered. Differential diagnosis included extramedullary myeloid sarcoma and an acute leukemia with ambiguous lineage. Absence of myeloperoxidase excluded myeloid sarcoma, and absence of CD34, myeloperoxidase, CD117, and muramidase ruled out acute leukemia. This diagnosis was confirmed by a senior hematopathologist and at major cancer center. At the time of this report outcome of the event was recovered on an unspecified date. Upon medical review, the case was considered as serious due to important medical event: Blastic Plasmacytoid Dendritic Neoplasm (BPDN). Documents held by sender: none.