A Case of a Giant Congenital Melanocytic Nevus Treated by Curettage with the Application of Cultured Epidermal Autografts before 6 Months of Age

Curettage is common in the treatment of a giant congenital melanocytic nevus (GCMN) in infants and should generally be performed before 6 months of age. Post-curettage retarded epithelialization often interferes with the ability to perform multiple operations within a short interval, and thus, it is difficult to treat large lesions in the neonatal period. We herein report a case of a GCMN comprising 20% of the total body surface area, which required multi-stage curettage, in which a cultured epithelial autograft was used to promote epithelialization of the post-curettage wound. The patient was a 1-month-old boy with a GCMN in his head, neck, chest, back, buttock, left upper arm, and a few satellite lesions. A four-stage operation was performed between 3 and 6 months of age; the cultured epithelial autograft took well after each operation, and complete epithelialization was observed at postoperative days 20, 23, 27, and 12, respectively. Seven months after the last surgery, hypertrophic scar formation was only observed in a small area of the left upper arm without axillary contracture. The color of the treated area improved, except for slight partial re-pigmentation. A skin biopsy was obtained from the re-pigmented area. The results demonstrated that nevus cells remained in the basal layer of the epidermis, hair follicles, and deep layer of the remaining dermis, suggesting that the recurrent nevus cells in the regenerated epidermis migrated from hair follicles. We conclude that the combination of curettage and the application of a cultured epithelial autograft is a promising option for GCMN treatment

A case of biventricular pacing with a spike on T-wave caused by the algorithm maintaining biventricular pacing rate

AbstractCardiac-resynchronization therapy (CRT) improves the cardiac function of patients with left ventricular (LV) dyssynchrony. Maintenance of the biventricular pacing rate is very important in managing the hemodynamics in patients implanted with CRT devices. A low biventricular pacing rate, for example, in cases with atrial fibrillation or rapid intrinsic atrioventricular (AV) conduction, decreases the benefits of CRT. The LUMAX HF-T 540 device series (BIOTRONIK, Berlin, Germany) has a LV-triggered pace algorithm, which allows biventicular pacing rates to be maintained even during rapid intrinsic rhythms caused by shortened AV conduction and/or premature ventricular contraction (PVC) occurring in the right ventricle. We encountered a case of CRT device implantation with a defibrillator wherein this triggered pace algorithm caused a spike on T-wave due to T-wave oversensing. By remote monitoring, we were also able to determine that the T-wave oversensing was due to a PVC. The LUMAX 540 series allows for changes in the sensing threshold and filter settings of the device, which facilitated the elimination of T-wave oversensing in this case

A case of Langerhans cell sarcoma on the scalp: Whole‐exome sequencing reveals a role of ultraviolet in the pathogenesis

Langerhans cell sarcoma (LCS) is a high‐grade neoplasm with overtly malignant cytological features and a Langerhans cell phenotype. The underlying genetic features are poorly understood, and only a few alterations, such as those of the MARK pathway‐related genes, CDKN2A and TP53 have been reported. Here we present a 70‐year‐old male with LCS on the scalp and pulmonary metastasis. The multinodular tumor, 3.0 cm in diameter, consisted of diffusely proliferated pleomorphic cells with numerous mitoses (53/10 HPFs). Immunohistochemically, the tumor cells were positive for CD1a, Langerin and PD‐L1, and the Ki‐67 labeling index was 50%. These pathological features were consistent with LCS, and were also observed in the metastatic tumor. Whole‐exome sequencing revealed that both the primary and metastatic tumors harbored a large number of mutations (>20 mutations/megabase), with deletion of CDKN2A and TP53 mutation, and highlighted that the mutational signature was predominantly characteristic of ultraviolet (UV) exposure (W = 0.828). Our results suggest, for the first time, that DNA damage by UV could accumulate in Langerhans cells and play a role in the pathogenesis of LCS. The high mutational burden and PD‐L1 expression in the tumor would provide a rationale for the use of immune checkpoint inhibitors for treatment of unresectable LCS

Implementation of a novel PCR based method for detecting malaria parasites from naturally infected mosquitoes in Papua New Guinea

<p>Abstract</p> <p>Background</p> <p>Detection of <it>Plasmodium species </it>in mosquitoes is important for designing vector control studies. However, most of the PCR-based detection methods show some potential limitations. The objective of this study was to introduce an effective PCR-based method for detecting <it>Plasmodium vivax </it>and <it>Plasmodium falciparum </it>from the field-caught mosquitoes of Papua New Guinea.</p> <p>Methods</p> <p>A method has been developed to concurrently detect mitochondrial cytochrome b (<it>Cyt b</it>) of four human <it>Plasmodium </it>species using PCR (<it>Cytb</it>-PCR). To particularly discriminate <it>P. falciparum </it>from <it>P. vivax</it>, <it>Plasmodium ovale </it>and <it>Plasmodium malariae</it>, a polymerase chain reaction-repeated fragment length polymorphism (PCR-RFLP) has further been developed to use with this method. However, due to limited samples number of <it>P. ovale </it>and <it>P. malariae</it>; this study was mainly confined to <it>P. vivax </it>and <it>P. falciparum</it>. The efficiency of <it>Cytb</it>-PCR was evaluated by comparing it with two 'gold standards' enzyme linked immunosorbent assay specific for circumsporozoite protein (CS-ELISA) using artificially infected mosquitoes; and nested PCR specific for small subunit ribosomal RNA (<it>SSUrRNA</it>) using field caught mosquitoes collected from three areas (Kaboibus, Wingei, and Jawia) of the East Sepic Province of Papua New Guinea.</p> <p>Results</p> <p>A total of 90 mosquitoes were artificially infected with three strains of <it>Plasmodium</it>: <it>P. vivax-</it>210 (<it>n </it>= 30), <it>P. vivax</it>-247 (<it>n </it>= 30) and <it>P. falciparum </it>(<it>n </it>= 30). These infected mosquitoes along with another 32 unfed mosquitoes were first checked for the presence of <it>Plasmodium </it>infection by CS-ELISA, and later the same samples were compared with the <it>Cytb</it>-PCR. CS-ELISA for <it>P. vivax</it>-210, <it>P. vivax</it>-247 and <it>P. falciparum </it>detected positive infection in 30, 19 and 18 mosquitoes respectively; whereas <it>Cytb</it>-PCR detected 27, 16 and 16 infections, respectively. The comparison revealed a close agreement between the two assays (κ = 0.862, 0.842 and 0.894, respectively for Pv-210, Pv-247 and <it>P. falciparum </it>groups). It was found that the eight CS-ELISA-positive mosquitoes detected negative by <it>Cytb</it>-PCR were false-positive results. The lowest detection limit of this <it>Cytb</it>-PCR was 10 sporozoites. A highly concordance result was also found between nested PCR and <it>Cytb</it>-PCR using 107 field caught mosquitoes, and both tests concordantly detected <it>P. falciparum </it>in an <it>Anopheles punctulatus </it>mosquito collected from Kaboibus. Both tests thus suggested an overall sporozoite rate of 0.9% (1/107) in the study areas. Subsequently, PCR-RFLP efficiently discriminated <it>P. falciparum </it>from <it>P. vivax </it>for all of the <it>Cytb</it>-PCR positive samples.</p> <p>Conclusion</p> <p>A single step PCR based method has been introduced here that is highly sensitive, efficient and reliable for identifying <it>P. vivax </it>and <it>P. falciparum </it>from mosquitoes. The reliability of the technique was confirmed by its ability to detect <it>Plasmodium </it>as efficiently as those of CS-ELISA and nested PCR. Application of the assay offers the opportunity to detect vector species of Papua New Guinea and may contribute for designing further vector control programmes.</p

A multilocular thymic cyst associated with mediastinal seminoma: evidence for its medullary epithelial origin highlighted by POU2F3-positive thymic tuft cells and concomitant myoid cell proliferation

Multilocular thymic cyst (MTC) and germ cell tumors are common diseases that impact the mediastinum. Correctly diagnosing these diseases can be difficult because several other conditions can mimic them. We report a male patient with MTC associated with mediastinal seminoma. A needle biopsy of the mediastinal tumor revealed numerous epithelioid cell granulomas that mimicked sarcoidosis or mycobacterial infection. However, large atypical cells positive for Oct3/4 and KIT were noted between the granulomas; thus, we diagnosed the patient with mediastinal seminoma. The resected tumor, after chemotherapy, consisted of multiple cystic lesions, and a residual germ cell tumor was first considered. However, thymic medulla-specific elements, namely, POU2F3-positive thymic tuft cells and rhabdomyomatous myoid cells accompanying the epithelium, led to the correct diagnosis of MTC. Our case underscores the importance of recognizing the histological features associated with mediastinal seminoma and provides novel findings for MTC pathogenesis, namely, the presence of thymic tuft cells

Squamous Cell Carcinoma of the Scalp after Artificial Hair Implantation

A 48-year-old man with a protruding tumor on the parietal region had undergone treatment of alopecia using artificial synthetic fibers 2 or 3 times a year for 10 years from 30 to 39 years old. Three months before the first consultation at our hospital, he noticed a small tumor that had gradually shown bleeding and discharge, with expansion of the affected area. A diagnosis of squamous cell carcinoma (SCC) was made based on a biopsy, and we resected the tumor with a 1-cm surgical margin from the reddened area around the protruding tumor (14 × 11 cm), including the periosteum membrane. No tight adhesion was found between the periosteum and skull, so we excised the outer table of the skull of the central part (diameter: 8 cm) for a pathological analysis. A pathological study showed moderately differentiated SCC with a negative surgical margin. The whole tumor was surrounded by scar tissue with buried artificial hair implants. The second surgery was performed on the 15th postoperative day. An anterolateral thigh flap was divided into 2 flaps to fit the circle-shaped wound. This is the second report of SCC developing after artificial hair implantation in the frontal-parietal scalp. The whole protruding tumor was surrounded by scar tissue with buried artificial hair implants. Proving the direct causal relationship between inflammation of scar tissue and SCC generation is difficult; however, our pathological findings support the possibility of the harmful effects of artificial hair implants