Basal cell carcinoma vs basaloid squamous cell carcinoma of the skin: an immunohistochemical reappraisal.

Typical cutaneous basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are morphologically dissimilar. It is well known, however, that poorly differentiated SCC may assume a basaloid phenotype, complicating the histologic distinction between these 2 neoplasms. Selected immunohistochemical stains have been used in the past to aid in that differential diagnosis. In the current study, additional markers were evaluated to determine whether they would be helpful in that regard. Twenty-nine cases of metatypical (squamoid) BCC (MBCC) and 25 examples of basaloid SCC (BSCC) were studied using the antibodies Ber-EP4 and MOC-31 as well as a plant lectin preparation from Ulex europaeus I (UEA-1). The resulting immunostains were interpreted independently by 3 pathologists, and the results showed that MBCCs demonstrated strong and diffuse staining for Ber-EP4 (25/29) and MOC-31 (29/29). In contrast, BSCCs tended to be only sporadically reactive for both markers (4/25 and 1/25 cases, respectively). Labeling for UEA-1 was observed in almost all BSCCs (24/25), but only 6 of 29 cases of MBCC showed limited, focal staining with that lectin. These data suggest that MOC-31 is a useful marker in the specified differential diagnosis, especially when used together with UEA-1.

Boric acid ingestion clinically mimicking toxic epidermal necrolysis.

The ingestion of large amounts of boric acid, a component of household insecticides, is a rare occurrence, characterized by a diffuse desquamative skin eruption, neutropenia, thrombocytopenia, delirium, acute renal failure and prolonged ileus. A 56-year-old male with a history of multiple previous suicide attempts was witnessed ingesting household roach killer and 4 days later presented to the hospital with lethargy, stiffness and a diffuse erythematous and desquamative eruption with bullous formation. He subsequently developed erythema of both palms as well as alopecia totalis. Histopathology from a right arm shave biopsy revealed a mostly intact epidermis with subtle vacuolar alteration of the basal layer, scattered intraepidermal apoptotic keratinocytes, parakeratosis with alternating layers of orthokeratosis and considerable superficial exfoliation; accompanying dermal changes included vasodilatation and mild perivascular inflammation. This report describes the cutaneous and systemic complications in a rare case of boric acid ingestion. There is little published material on the symptoms and histopathology following boric acid ingestion, but knowledge of this entity is important, both to differentiate it from other causes of desquamative skin rashes and to allow the initiation of appropriate clinical care.

Direct calibration in megavoltage photon beams using Monte Carlo conversion factor: validation and clinical implications.

The Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) has established a method for ionisation chamber calibrations using megavoltage photon reference beams. The new method will reduce the calibration uncertainty compared to a (60)Co calibration combined with the TRS-398 energy correction factor. The calibration method employs a graphite calorimeter and a Monte Carlo (MC) conversion factor to convert the absolute dose to graphite to absorbed dose to water. EGSnrc is used to model the linac head and doses in the calorimeter and water phantom. The linac model is validated by comparing measured and modelled PDDs and profiles. The relative standard uncertainties in the calibration factors at the ARPANSA beam qualities were found to be 0.47% at 6 MV, 0.51% at 10 MV and 0.46% for the 18 MV beam. A comparison with the Bureau International des Poids et Mesures (BIPM) as part of the key comparison BIPM.RI(I)-K6 gave results of 0.9965(55), 0.9924(60) and 0.9932(59) for the 6, 10 and 18 MV beams, respectively, with all beams within 1σ of the participant average. The measured kQ values for an NE2571 Farmer chamber were found to be lower than those in TRS-398 but are consistent with published measured and modelled values. Users can expect a shift in the calibration factor at user energies of an NE2571 chamber between 0.4-1.1% across the range of calibration energies compared to the current calibration method.

Ex vivo rehabilitation of non-heart-beating donor lungs in preclinical porcine model: delayed perfusion results in superior lung function.

OBJECTIVES: Ex vivo lung perfusion (EVLP) is a promising modality for the evaluation and treatment of marginal donor lungs. The optimal timing of EVLP initiation and the potential for rehabilitation of donor lungs with extended warm ischemic times is unknown. The present study compared the efficacy of different treatment strategies for uncontrolled non-heart-beating donor lungs. METHODS: Mature swine underwent hypoxic arrest, followed by 60 minutes of no-touch warm ischemia. The lungs were harvested and flushed with 4°C Perfadex. Three groups (n = 5/group) were stratified according to the preservation method: cold static preservation (CSP; 4 hours of 4°C storage), immediate EVLP (I-EVLP: 4 hours EVLP at 37°C), and delayed EVLP (D-EVLP; 4 hours of CSP followed by 4 hours of EVLP). The EVLP groups were perfused with Steen solution supplemented with heparin, methylprednisolone, cefazolin, and an adenosine 2A receptor agonist. The lungs then underwent allotransplantation and 4 hours of recipient reperfusion before allograft assessment for resultant ischemia-reperfusion injury. RESULTS: The donor blood oxygenation (partial pressure of oxygen/fraction of inspired oxygen ratio) before death was not different between the groups. The oxygenation after transplantation was significantly greater in the D-EVLP group than in the I-EVLP or CSP groups. The mean airway pressure, pulmonary artery pressure, and expression of interleukin-8, interleukin-1ß, and tumor necrosis factor-α were all significantly reduced in the D-EVLP group. Post-transplant oxygenation exceeded the acceptable clinical levels only in the D-EVLP group. CONCLUSIONS: Uncontrolled non-heart-beating donor lungs with extended warm ischemia can be reconditioned for successful transplantation. The combination of CSP and EVLP in the D-EVLP group was necessary to obtain optimal post-transplant function. This finding, if confirmed clinically, will allow expanded use of nonheart-beating donor lungs.

Pretreatment strategy with adenosine A2A receptor agonist attenuates reperfusion injury in a preclinical porcine lung transplantation model.

OBJECTIVE: Adenosine A(2A) receptor activation after lung transplantation attenuates ischemia-reperfusion injury by reducing inflammation. However, the effect of adenosine A(2A) receptor activation in donor lungs before transplant remains ill defined. This study compares the efficacy of 3 different treatment strategies for adenosine A(2A) receptor agonist in a clinically relevant porcine lung transplantation model. METHODS: Mature porcine lungs underwent 6 hours of cold ischemia before allotransplantation and 4 hours of reperfusion. Five groups (n = 6/group) were evaluated on the basis of treatment with ATL-1223, a selective adenosine A(2A) receptor agonist: thoracotomy alone (sham), transplant alone (ischemia-reperfusion), donor pretreatment via ATL-1223 bolus (ATL-D), recipient treatment via ATL-1223 infusion (ATL-R), and a combination of both ATL-1223 treatments (ATL-D/R). Lung function and injury were compared. RESULTS: Blood oxygenation was significantly higher among ATL-D, ATL-R, and ATL-D/R groups versus ischemia-reperfusion (392.0 ± 52.5, 428.9 ± 25.5, and 509.4 ± 25.1 vs 77.2 ± 17.0 mm Hg, respectively, P < .001). ATL-1223-treated groups had lower pulmonary artery pressures (ATL-D = 30.5 ± 1.8, ATL-R = 30.2 ± 3.3, and ATL-D/R = 29.3 ± 4.5 vs IR = 45.2 ± 2.1 mm Hg, P < .001) and lower mean airway pressures versus ischemia-reperfusion (ATL-D = 9.1 ± 0.8, ATL-R = 9.1 ± 2.6, and ATL-D/R = 9.6 ± 1.3 vs IR = 21.1 mm Hg, P < .001). Likewise, ATL-1223-treated groups had significantly lower lung wet/dry weight, proinflammatory cytokine expression, and lung injury scores by histology compared with ischemia-reperfusion. All parameters of lung function and injury in ATL-1223-treated groups were similar to sham (all P > .05). CONCLUSIONS: Pretreatment of donor lungs with ATL-1223 was as efficacious as other treatment strategies in protecting against ischemia-reperfusion injury. If necessary, supplemental treatment of recipients with ATL-1223 may provide additional protection. These results support the development of pharmacologic A(2A)R agonists for use in human clinical trials for lung transplantation.