flt3 In our report a case

In our report, a case of metastatic SCC from a very serious diffuse PEODDN was presented. This case demonstrated very serious lesions with closely grouped thornlike projections with very large plugs and verrucous plaques. This was a very rare finding because of its wide distributions, serious lesions, and poorly differentiated invasive SCC with lymph node metastasis. To the best of our knowledge, no similar case in the literature has yet been reported. PEODDN\'s association with Bowen\'s disease and SCC has been described only in two cases. Coras et al presented the case of a 49-year-old woman with local PEODDN on her left sole where SCC in situ developed. Nassiri and Hansen presented the case of a 39-year-old woman with widespread PEODDN and diffuse ulcers, and reported the occurrence of SCC in situ or invasive SCC from 11 months of age. However, whether PEODDN\'s relationship with SCC is a coincidental or true association remains to be uncovered because of its rarity. It has been speculated that abnormal epidermal flt3 under the parakeratotic columns may be prone to malignant degeneration. It was also reported that p53 gene mutations are responsible for the progression of porokeratosis to SCC. The role of the p53 gene in the progression of PEODDN to SCC needs further research.
Acknowledgments
Introduction Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematologic malignancy that originates from the precursors of plasmacytoid dendritic cells. It was originally called a CD4/CD56 hematodermic neoplasm and subsequently regarded as a blastic variant of NK/T cell lymphoma, owing to the expression of CD56, in the third edition of the “WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues”. In the 2008 edition of the WHO classification, this entity was renamed as BPDCN and listed under the category of acute myeloid leukemia (AML) and related precursor neoplasms because it was found to be a neoplasm derived from the precursors of plasmacytoid dendritic cells. It is an aggressive hematologic malignancy that occurs mainly in elderly individuals, but childhood cases have been reported. Our experience of the diagnosis of a cutaneous case of BPDCN is reported, and the current literatures is reviewed.
Case Report An 86-year-old man with two asymptomatic nodular plaques on his scalp was referred to our hospital under a diagnosis of extranodal NK/T cell lymphoma because of its CD56 immunopositivity. Upon examination, the patient had two erythematous and violaceous nodular plaques measuring 5 cm on his parietal and temple scalp that had been present for 5 months and 2 months, respectively (Figure 1A). Another 1.5-cm nodule was found on his back (Figure 1B). The nodules were not ulcerated. The tumor on the parietal scalp was rebiopsied. Microscopically, the tumor showed diffuse infiltrates of monomorphous, medium-sized, blast-like cells with round to oval nuclei, small nucleoli, and limited cytoplasm throughout the dermis extending into the subcutis (Figures 2A and 2B). No epidermotropism was observed, and a Grenz zone was present below the epidermis. Pilosebaceous structures were not involved. Brisk mitosis was observed, and there was hemorrhage in the superficial dermis, but no necrosis or angioinvasion was found. Immunohistochemically, the tumor cells were positive for CD4, CD33, CD56, CD68 (KP1), CD123, and TCL-1 (Figure 2), and negative for CD3, CD20, CD10, Bcl-6, CD30, ALK, myeloperoxidase, lysozyme, and granzyme B (Figure 2). The immunophenotype of CD4, CD56, CD123, and TCL-1 with negative granzyme B and myeloperoxidase established the diagnosis of BPDCN. EBER in situ hybridization was not performed because the histopathological and immunohistochemical studies did not support a diagnosis of extranodal NK/T cell lymphoma. A whole-body computed tomographic study revealed no hepatosplenomegaly, but mild swelling of the submandibular, neck, and axillary lymph nodes was noted, and a core needle biopsy of the submandibular lymph nodes showed similar blast-like cells expressing CD4, CD56, and CD123. Laboratory tests showed a white blood cell count of 3.9 × 109/L with normal ranges of the differential count. No blast cells were observed. The hemoglobin level was 12.1 g/dL, the platelet count was 135 × 109/L, the alanine aminotransferase level was 11 U/L, and the lactic acid dehydrogenase level was 195 U/L. We did not perform chromosomal analysis or a T-cell receptor gene rearrangement study, and the patient refused a bone marrow biopsy. Because of his advanced age, the patient was treated with palliative oral prednisolone (30 mg/d). We have followed the patient for 6 months, and the tumors lave been progressively regressing (Figures 1C and 1D).