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61.
Background Cryotherapy is a physical procedure whose immunogenic capability enables it to destroy tumour cells, at least partially. Consequently, it can boost the effect of imiquimod. Objective The objective of the present study was to evaluate the efficacy of combining cryotherapy and imiquimod in patients who did not achieve a complete response after treatment of basal cell carcinoma with imiquimod. The study sample comprised 22 patients with 23 basal cell carcinomas. The tumours were treated with liquid nitrogen (one cycle, 20–30 s) before application of imiquimod (five times weekly for 6 weeks). Results A maintained complete clinical response was observed in 19 of the 23 tumours (83%), a partial response in three and no response in one. One tumour presented signs of persistence/recurrence during follow‐up. Conclusions Cryotherapy applied to treat imiquimod‐refractory basal cell carcinoma seems to sensitize the tumour to the effect of the drug, thus reducing the percentage of patients who need surgery after an incomplete response to imiquimod. Further studies are necessary to confirm these findings.  相似文献   
62.
Carcinosarcomas are biphasic tumors composed of admixed malignant epithelial and mesenchymal components. Numerous terms have been used to name such neoplasms; therefore, terminological confusion is frequent. Most examples of carcinosarcomas are encountered in non‐cutaneous sites, with approximately 100 cases of cutaneous carcinosarcomas reported so far in the English literature. Although different theories have been suggested to explain the occurrence of these peculiar neoplasms, histogenetic mechanisms should be better hypothesized depending on each individual case. Even though prognosis tends to be related to the specific components of the lesion, especially the epithelial one, it seems that cases of cutaneous localization usually have a better outcome. We report an exceedingly rare case of syringocystadenocarcinoma papilliferum which showed an atypical stroma with sarcomatoid appearance, and highlight that the terminology used for this spectrum of lesions is disorganized and confusing.  相似文献   
63.
We review the spectrum of cutaneous disorders associated with inflammatory and neoplastic plasmacytic pathology. Because plasma cells are derived from B‐lymphocytes our overview includes discussion of certain lymphoplasmacytic proliferations. It is structured along histopathological lines, addressing conditions characterized by (a) cutaneous plasma cell infiltrates, (b) deposits of plasma cell products or their derivatives in the skin and (c) miscellaneous, poorly understood cutaneous complications of plasmacytic disorders. Lesions arising primarily in the skin and those due to cutaneous involvement by multisystem disorders are addressed. The range includes a spectrum of tumefactive and circulatory manifestations. We highlight key clinical and pathological features of the different conditions and outline recent advances in our understanding of these entities. By emphasizing the dermatopathological characteristics of this spectrum of disorders we hope to hone the diagnostic accuracy of practitioners in the field.  相似文献   
64.
65.
Dabska tumor, also known as papillary intralymphatic angioendothelioma (PILA), is a locally aggressive hemangiendothelioma characterized by intravascular papillary proliferations of atypical endothelial cells. Besides PILA, papillary tufts lined by hobnail endothelial cells have been rarely described in vascular proliferations. We report two cases of acquired hemangiomas, which focally showed this finding. We present a 15‐year‐old male and a 7‐year‐old girl with erythematous nodules. Both lesions were composed of capillary lobules intermingled with large sinusoidal spaces lined with a single layer of flat endothelial cells, which focally developed intravascular papillary proliferations lined by plump hyperchromatic endothelial cells and a central connective tissue core. Both types of cells were positive with CD31 and ERG and negative for Lyve‐1, Prox‐1 and podoplanin. Wilm's tumor 1 marker was strongly positive in the capillary hemangioma areas while negative in the intravascular tufts. Both lesions recurred after the first excision but we did not observe further recurrence or evidence of metastasis in the follow‐up. In summary, our cases expand the histopathologic findings that may be seen in conventional acquired capillary hemangiomas. The focal presence of dabskoid tufts within an otherwise conventional capillary hemangioma should be not misinterpreted as evidence of malignancy.  相似文献   
66.
Desmoplastic melanoma (DM) and cutaneous malignant peripheral nerve sheath tumors (MPNST) reveal histological and immunohistochemical similarities, including S100 positivity and negative staining for conventional melanocytic markers. We present 3 cases of cutaneous S100‐positive spindle cell tumors in elderly patients, in which first findings led to initial misdiagnoses as cutaneous MPNST and benign peripheral sheath nerve tumor (neurofibroma). The identification of adjacent atypical melanocytic hyperplasia in the overlying skin along with tumor cell proliferation, also in the superficial dermis, the neurotropic component and the absence of any relationship between the tumor and a major nerve, pre‐existing neural benign tumor or the existence of stigmata suggestive of neurofibromatosis raised consideration of a DM. Careful attention should be paid to the presence of a firm dermal nodule and atypical scar lesions especially in sun‐exposed areas (mainly head and neck region) in elderly patients associated with S100‐positive spindle cell proliferation, solar elastosis and adjacent atypical melanocytic proliferation. In such cases, the possibility of a DM should be excluded with caution, especially if the tumor reveals a paucicellular morphology resembling various non‐melanocytic neoplasms including malignant or benign peripheral sheath nerve tumors.  相似文献   
67.
Folliculo‐sebaceous hamartomas comprise a series of entities whose boundaries are imprecise. We present the clinical case of a folliculo‐sebaceous cystic hamartoma of genital localization where the diagnosis was established based on the epithelial proliferation, but mostly, on the characteristic stroma. Because this lesion lacked of the cystic component, we mention the most frequent differential diagnoses and review the literature of the few cases published on this infrequent localization.  相似文献   
68.
We describe 3 cases of multiple histiocytic cutaneous tumors that began in childhood and affected 3 members from 2 generations of the same family: a mother, a daughter and a nephew. The lesions were mostly skin‐colored papules distributed symmetrically on the dorsum of the forearms and hands and on the face and thighs. There were no signs of spontaneous regression. The clinical and histopathological features were consistent with a diagnosis of hereditary progressive mucinous histiocytosis (HPMH), but phenotypic expression varied somewhat between the 3 patients. HPMH has only been described in 8 families to date, and just one of the reports included 3 well‐documented cases. Our cases confirm that HPMH can affect males and expands the clinical spectrum of skin lesions in this disease.  相似文献   
69.
We present the case of a 35‐year‐old man who developed a follicular differentiated cutaneous carcinoma with an eosinophil‐rich infiltrate and an aggressive clinical behavior. After an in‐depth histopathological investigation the diagnosis of trichoblastic carcinoma was made. Over the course of the disease the patient developed a cutaneous in‐transit metastasis as well as an axillary lymph node metastasis 18 months after the excision of the primary tumor on his back. Based on a literature review we discuss the different concepts behind the term “trichoblastic carcinoma” and we summarize the clinical and histological details of previously reported cases. Furthermore, we focus on the phenomenon of tumor‐associated eosinophilia.  相似文献   
70.
Pediatric traumatic brain injury (TBI) is a major cause of acquired cognitive dysfunction in children. Hippocampal Brain Derived Neurotrophic Factor (BDNF) is important for normal cognition. Little is known about the effects of TBI on BDNF levels in the developing hippocampus. We used controlled cortical impact (CCI) in the 17 day old rat pup to test the hypothesis that CCI would first increase rat hippocampal BDNF mRNA/protein levels relative to SHAM and Na?ve rats by post injury day (PID) 2 and then decrease BDNF mRNA/protein by PID14. Relative to SHAM, CCI did not change BDNF mRNA/protein levels in the injured hippocampus in the first 2 days after injury but did decrease BDNF protein at PID14. Surprisingly, BDNF mRNA decreased at PID 1, 3, 7 and 14, and BDNF protein decreased at PID 2, in SHAM and CCI hippocampi relative to Na?ve. In conclusion, TBI decreased BDNF protein in the injured rat pup hippocampus 14 days after injury. BDNF mRNA levels decreased in both CCI and SHAM hippocampi relative to Na?ve, suggesting that certain aspects of the experimental paradigm (such as craniotomy, anesthesia, and/or maternal separation) may decrease the expression of BDNF in the developing hippocampus. While BDNF is important for normal cognition, no inferences can be made regarding the cognitive impact of any of these factors. Such findings, however, suggest that meticulous attention to the experimental paradigm, and possible inclusion of a Na?ve group, is warranted in studies of BDNF expression in the developing brain after TBI.  相似文献   
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