Indications and pitfalls of immunohistochemistry in head and neck cancer

Immunohistochemistry (IHC) has been employed in the differential diagnosis of tumors.ObjectiveTo assess the use of IHC in cases of head and neck tumor.MethodThis is a retrospective study of the cases included in the Cancer Registry of the institution.ResultsIHC was used in 76 (11%) of 704 pathology tests. Most cases were carcinomas (85.80%), and 83.66% of them were squamous cell carcinomas. All tests were done with diagnostic purposes. The most frequently used antibodies were 34BE12 (37.18%), AE1/AE3 (35.9%), 35BH11 (28.21%), CD45 (25.64%), CD20 (24.36%), CD30 (24.36%), CK7 (23.08%) and CD3 (23.08%).ConclusionsIHC was used in 10.67% of the head and neck tumor cases submitted to pathology testing, mostly for carcinoma (5.26%). In the determination of squamous cell carcinoma, IHC accounted for 18.42% of all tumors.     

Neurophysiological Testing to Assess Penile Sensory Nerve Damage After Radical Prostatectomy

IntroductionRadical prostatectomy (RP) can lead to erectile dysfunction due to surgical injury of the cavernous nerves. However, there is no simple, objective test to evaluate cavernous nerve damage caused by RP in clinical practice.AimTo assess the value of the measurement of penile thermal and vibratory sensory thresholds to reflect cavernous nerve damage caused by RP.MethodsWe included 42 consecutive patients who underwent RP with cavernous nerve sparing (laparoscopic approach, N = 12) or without cavernous nerve sparing (laparoscopic, N = 13; retropubic, N = 11; or transperineal, N = 6). Penile thermal (warm and cold) and vibratory sensory thresholds were measured twice, together with the Erectile Dysfunction Symptom Score (EDSS), 1 month before and 2 months after RP.Main Outcome MeasuresPenile sensory thresholds for warm, cold, and vibration sensations.ResultsPenile sensory thresholds for warm (P < 0.0001) and cold (P < 0.0001) sensations significantly increased after non‐nerve‐sparing RP, but not after nerve‐sparing RP. Vibration threshold only increased after transperineal non‐nerve‐sparing RP (P = 0.031). EDSS values were significantly increased in all groups of patients 2 months after surgery.ConclusionsSensory nerve fibers carrying penile skin sensations travel with the cavernous nerves in the pelvis. Therefore, testing these sensations may help to evaluate the extent of cavernous nerve damage caused by RP. In this series, post‐operative changes in penile sensory thresholds differed with the surgical technique of RP, as the cavernous nerves were preserved or not. The present results support the value of quantitative penile sensory threshold measurement to indicate RP‐induced cavernous nerve injury. Yiou R, De Laet K, Hisano M, Salomon L, Abbou C‐C, and Lefaucheur J‐P. Neurophysiological testing to assess penile sensory nerve damage after radical prostatectomy. J Sex Med 2012;9:2457–2466.     

The effects of low-level laser irradiation on bone tissue in diabetic rats

Diabetes mellitus (DM) leads to a decrease in bone mass and increase the risk of osteoporosis and in this context, many treatments have shown to accelerate bone metabolism. It seems that low-level laser therapy (LLLT) is able of stimulating osteoblast activity and produced increased biomechanical properties. However, its effects on bone in diabetic rats are not fully elucidated. The aim of this study was to evaluate the effects of LLLT on bone formation, immunoexpression of osteogenic factors, biomechanical properties and densitometric parameters in diabetic rats. Thirty male Wistar rats were randomly distributed into three experimental groups: control group, diabetic group, and laser-treated diabetic group. DM was induced by streptozotocin (STZ) and after 1 week laser treatment started. An 830-nm laser was used, performed for 18 sessions, during 6 weeks. At the end of the experiment, animals were euthanized and tibias and femurs were defleshed for analysis. Extensive resorptive areas as a result of osteoclasts activity were noticed in DG when compared to control. Laser-treated animals showed an increased cortical area. The immunohistochemical analysis revealed that LLLT produced an increased RUNX-2 expression compared to other groups. Similar RANK-L immunoexpression was observed for all experimental groups. In addition, laser irradiation produced a statistically increase in fracture force, bone mineral content (BMC) and bone mineral density compared to DG. The results of this study indicate that the STZ model was efficient in inducing DM 1 and producing a decrease in cortical diameter, biomechanical properties and in densitometric variables. In addition, it seems that LLLT stimulated bone metabolism, decreased resorptive areas, increased RUNX-2 expression, cortical area, fracture force, BMD, and BMC. Further studies should be developed to provide additional information concerning the mechanisms of action of laser therapy in diabetic bone in experimental and clinical trials.