Neuromuscular involvement in COVID-19 critically ill patients

OBJECTIVE

Coronavirus disease 2019 (COVID-19) has a high incidence of intensive care admittance due to the severe acute respiratory syndrome (SARS). Intensive care unit (ICU)-acquired weakness (ICUAW) is a common complication of ICU patients consisting of symmetric and generalised weakness. The aim of this study was to determine the presence of myopathy, neuropathy or both in ICU patients affected by COVID-19 and whether ICUAW associated with COVID-19 differs from other aetiologies.

METHODS

Twelve SARS CoV-2 positive patients referred with the suspicion of critical illness myopathy (CIM) or polyneuropathy (CIP) were included between March and May 2020. Nerve conduction and concentric needle electromyography were performed in all patients while admitted to the hospital. Muscle biopsies were obtained in three patients.

RESULTS

Four patients presented signs of a sensory-motor axonal polyneuropathy and seven patients showed signs of myopathy. One muscle biopsy showed scattered necrotic and regenerative fibres without inflammatory signs. The other two biopsies showed non-specific myopathic findings.

CONCLUSIONS

We have not found any distinctive features in the studies of the ICU patients affected by SARS-CoV-2 infection.

SIGNIFICANCE

Further studies are needed to determine whether COVID-19-related CIM/CIP has different features from other aetiologies. Neurophysiological studies are essential in the diagnosis of these patients.

Clinicopathological features and prognostic significance of CTNNB1 mutation in low-grade, early-stage endometrial endometrioid carcinoma

Low-grade and early-stage endometrioid endometrial carcinomas (EECs) have an overall good prognosis but biomarkers identifying patients at risk of relapse are still lacking. Recently, CTNNB1 exon 3 mutation has been identified as a potential risk factor of recurrence in these patients. We evaluate the prognostic value of CTNNB1 mutation in a single-centre cohort of 218 low-grade, early-stage EECs, and the correlation with beta-catenin and LEF1 immunohistochemistry as candidate surrogate markers. CTNNB1 exon 3 hotspot mutations were evaluated by Sanger sequencing. Immunohistochemical staining of mismatch repair proteins (MLH1, PMS2, MSH2, and MSH6), p53, beta-catenin, and LEF1 was performed in representative tissue microarrays. Tumours were also reviewed for mucinous and squamous differentiation, and MELF pattern. Nineteen (8.7%) tumours harboured a mutation in CTNNB1 exon 3. Nuclear beta-catenin and LEF1 were significantly associated with CTNNB1 mutation, showing nuclear beta-catenin a better specificity and positive predictive value for CTNNB1 mutation. Tumours with CTNNB1 exon 3 mutation were associated with reduced disease-free survival (p = 0.010), but no impact on overall survival was found (p = 0.807). The risk of relapse in tumours with CTNNB1 exon 3 mutation was independent of FIGO stage, tumour grade, mismatch repair protein expression, or the presence of lymphovascular space invasion. CTNNB1 exon 3 mutation has a negative impact on disease-free survival in low-grade, early-stage EECs. Nuclear beta-catenin shows a higher positive predictive value than LEF1 for CTNNB1 exon 3 mutation in these tumours.

Postoperative management of patients with pituitary tumors submitted to pituitary surgery. Experience of a Spanish Pituitary Tumor Center of Excellence

There is a lack of evidence on timing, frequency, and duration of postoperative endocrine, radiologic, and ophthalmologic assessments that should be performed after pituitary surgery (PS). However, it is known that careful optimization of treatment and follow-up strategies as well as a multidisciplinary approach may have a significant impact on long-term outcomes, improving surgical results, minimize complications and facilitate their correct treatment if occurring, and optimize the hormonal, ophthalmological, and radiological reassessment throughout the follow-up. Considering that there are no specific guidelines on the postoperative management of patients with pituitary tumors (PT), we present our protocol for the postoperative management of patients with PT. It has been elaborated by the multidisciplinary team of a Spanish Pituitary Tumor Center of Excellence (PTCE) that includes at least one neurosurgeon, ENT, neuroradiologist, neuro-ophthalmologist, endocrine pathologist and endocrinologist specialized in pituitary diseases. We elaborated this guideline with the aim of sharing our experience with other centers involved in the management of PT thereby facilitating the postoperative management of patients submitted to PS.

RNA SARS-CoV-2 Persistence in the Lung of Severe COVID-19 Patients: A Case Series of Autopsies

The exact role of viral replication in patients with severe COVID-19 has not been extensively studied, and it has only been possible to demonstrate the presence of replicative virus for more than 3 months in a few cases using different techniques. Our objective was to study the presence of RNA SARS-CoV-2 in autopsy samples of patients who died from COVID-19 long after the onset of symptoms. Secondary superimposed pulmonary infections present in these patients were also studied. We present an autopsy series of 27 COVID-19 patients with long disease duration, where pulmonary and extrapulmonary samples were obtained. In addition to histopathological analysis, viral genomic RNA (gRNA) and viral subgenomic RNA (sgRNA) were detected using RT-PCR and in situ hybridization, and viral protein was detected using immunohistochemistry. This series includes 26 adults with a median duration of 39 days from onset of symptoms to death (ranging 9–108 days), 92% of them subjected to immunomodulatory therapy, and an infant patient. We detected gRNA in the lung of all but one patient, including those with longer disease duration. SgRNA was detected in 11 out of 17 patients (64.7%) with illness duration up to 6 weeks and in 3 out of 9 patients (33.3%) with more than 6 weeks of disease progression. Viral protein was detected using immunohistochemistry and viral mRNA was detected using in situ hybridization in 3 out of 4 adult patients with illness duration of <2 weeks, but in none of the 23 adult patients with an illness duration of >2 weeks. A remarkable result was the detection of viral protein, gRNA and sgRNA in the lung cells of the pediatric patient after 95 days of illness. Additional pulmonary infections included: 9 acute bronchopneumonia, 2 aspergillosis, 2 cytomegalovirus, and 1 BK virus infection. These results suggest that in severe COVID-19, SARS-CoV-2 could persist for longer periods than expected, especially in immunocompromised populations, contributing to the persistence of chronic lung lesions. Additional infections contribute to the fatal course of the disease.

In-depth quantitative proteomics analysis revealed C1GALT1 depletion in ECC-1 cells mimics an aggressive endometrial cancer phenotype observed in cancer patients with low C1GALT1 expression

BACKGROUND

Endometrial cancer (EC) is the most common cancer of the female reproductive organs. Despite the good overall prognosis of most low-grade ECs, FIGO I and FIGO II patients might experience tumor recurrence and worse prognosis. The study of alterations related to EC pathogenesis might help to get insights into underlying mechanisms involved in EC development and progression.

METHODS

Core tumoral samples were used to investigate the role of C1GALT1 in EC by immunohistochemistry (IHC). ECC-1 cells were used as endometrioid EC model to investigate the effect of C1GALT1 depletion using C1GALT1 specific shRNAs. SILAC quantitative proteomics analyses and cell-based assays, PCR, qPCR, WB, dot-blot and IHC analyses were used to identify, quantify and validate dysregulation of proteins.

RESULTS

Low C1GALT1 protein expression levels associate to a more aggressive phenotype of EC. Out of 5208 proteins identified and quantified by LC-MS/MS, 100 proteins showed dysregulation (log2fold-change ≥ 0.58 or ≤-0.58) in the cell protein extracts and 144 in the secretome of C1GALT1 depleted ECC-1 cells. Nine dysregulated proteins were validated. Bioinformatics analyses pointed out to an increase in pathways associated with an aggressive phenotype. This finding was corroborated by loss-of-function cell-based assays demonstrating higher proliferation, invasion, migration, colony formation and angiogenesis capacity in C1GALT1 depleted cells. These effects were associated to the overexpression of ANXA1, as demonstrated by ANXA1 transient silencing cell-based assays, and thus, correlating C1GALT and ANXA1 protein expression and biological effects. Finally, the negative protein expression correlation found by proteomics between C1GALT1 and LGALS3 was confirmed by IHC.

CONCLUSION

C1GALT1 stably depleted ECC-1 cells mimic an EC aggressive phenotype observed in patients and might be useful for the identification and validation of EC markers of progression.

Protocol for presurgical and anesthetic management of pheochromocytomas and sympathetic paragangliomas: a multidisciplinary approach

OBJECTIVE

To offer a practical guide for the presurgical and anesthetic management of pheochromocytomas and sympathetic paragangliomas (PGLs).

METHODS

This protocol was based on a comprehensive review of the literature and on our own multidisciplinary team's experience from managing pheochromocytoma and sympathetic PGLs at a referral center.

RESULTS

Patients with pheochromocytomas and sympathetic paragangliomas (PGLs) may develop potentially life-threatening complications, especially during surgical procedures. A complete biochemical, radiological, genetic, and cardiological assessment is recommended in the preoperative stage as it provides an evaluation of the risk of surgical complications and malignancy, allowing individualization of the presurgical treatment. Treatment with α-blockade and proper volume expansion in the preoperative stage significantly reduces the perioperative morbidity. During surgery, the anesthesiologist should look for a deep anesthetic level that inhibits the cardiovascular effects of catecholamines to minimize the risk of intraoperative complications.

CONCLUSIONS

An optimal presurgical evaluation of pheochromocytomas/ sympathetic PGL requires a multidisciplinary approach, including a complete hormonal, radiological, cardiac, genetic, and functioning evaluation in most cases. A proper preoperative evaluation in combination with strict blood pressure and heart rate control, and blood volume status optimization, will significantly reduce the risk of intraoperative and perioperative complications. In those patients who unfortunately develop intraoperative complications, the role of the anesthesiologist is essential since the selection of the appropriate management has a direct impact on morbimortality reduction.

Neuropathological findings in fatal COVID-19 and their associated neurological clinical manifestations

Severe cases of Coronavirus Disease 2019 (COVID-19) can present with multiple neurological symptoms. The available neuropathological studies have described different lesions; the most frequent was the presence of neuroinflammation and vascular-related lesions. The objective of this study was to report the neuropathological studies performed in a medical institution, with abundant long intensive care unit stays, and their associated clinical manifestations. This is a retrospective monocentric case series study based on the neuropathological reports of 13 autopsies with a wide range of illness duration (13–108 days). A neuroinflammatory score was calculated based on the quantification of CD8- and CD68-positive cells in representative areas of the central nervous system. This score was correlated afterwards with illness duration and parameters related to systemic inflammation. Widespread microglial and cytotoxic T-cell activation was found in all patients. There was no correlation between the neuroinflammatory score and the duration of the illness; nor with parameters of systemic inflammation such as the peak of IL-6 or the HScore (a parameter of systemic macrophage activation syndrome). Two patients had global hypoxic ischaemic damage and five patients had subacute infarcts. One patient had many more brain vascular microthrombi compared to the others and multiple subacute pituitary infarcts. SARS-CoV-2 RNA was not detected with qRT-PCR. The proportion of brain lesions in severe COVID-19 patients could be related to illness duration. In our series, with abundant long hospitalisation stays, neuroinflammation was present in all patients and was more prominent between day 34 and day 45 after onset of symptoms. Clinical correlation showed that two patients with the highest neuroinflammatory scores had severe encephalopathies that were not attributable to any other cause. The second most frequent lesions were related to vascular pathology.

Multidisciplinary protocol of preoperative and surgical management of patients with pituitary tumors candidates to pituitary surgery

The optimal planning of preoperative diagnosis, management and treatment of pituitary tumors (PT) candidates to pituitary surgery (PS) requires a multidisciplinary approach involving a team of endocrinologists, neurosurgeons, ENT, neuro-ophthalmologists and neuroradiologists with experience in pituitary diseases. Such teams improve surgical results, minimize complications and facilitate their correct treatment if occurring, and optimize the hormonal, ophthalmological and radiological preoperative and follow-up evaluation. We have developed a clinical practice protocol for patients with PT who are candidates to PS based on the most recent national and international guidelines and the relevant literature regarding PT published in the last years. The protocol has been elaborated by a multidisciplinary team of a Spanish Pituitary Tumor Center of Excellence (PTCE) that includes at least one neurosurgeon, ENT, neuroradiologist, neuro-ophthalmologist, endocrine pathologist and endocrinologist specialized in pituitary diseases. We elaborated this guideline with the aim of sharing our experience with other centers involved in the perioperative and surgical management of PT thereby facilitating the management of patients undergoing PS.

Presurgical somatostatin receptor ligand treatment does not affect tumor consistency in GH-secreting pituitary macroadenomas

PURPOSE

To evaluate whether presurgical treatment using long-acting somatostatin receptor ligands (SRL) may change pituitary tumor consistency and improve surgical outcome in GH-secreting pituitary macroadenomas.

METHODS

Retrospective study of 40 patients with GH-secreting pituitary macroadenomas operated for the first time by endoscopic transsphenoidal approach. Tumor consistency was evaluated intraoperatively and then correlated with histopathological fibrosis parameters and surgical outcomes. Surgical remission was reported based on the 2010 criteria.

RESULTS

The mean tumor size of GH-secreting macroadenomas was of 16.9 ± 8.2 mm and 25 were invasive pituitary adenomas (PAs). Presurgical treatment with long-acting SRL was performed in 17 patients (11 lanreotide, 6 octreotide). The cure rate was higher in those patients pre-treated with monthly doses ≥30 mg of octreotide or ≥90 mg of lanreotide than in those treated with lower doses or untreated (8/11 (72.7%) vs 11/29 (37.9%), P = 0.049). However, although the proportion of soft tumors increased as higher doses of SRL were considered in the pre-treated group, no statistical significance was reached, even when the highest approved monthly doses were used (6/6 (100%) vs 23/34 (67.7%), P = 0.102). Moreover, we found that the remission rate was similar between fibrous and soft tumors (P = 0.873) and also of surgical complications (P = 0.859), despite of the higher prevalence of Knosp >2 (P = 0.035) and very large PA (P = 0.025) in fibrous tumors than in soft tumors.

CONCLUSIONS

Although presurgical treatment with high doses of SRL was associated with a 2.2-fold greater chance of surgical remission, this benefit was not related with changes in tumor consistency induced by the presurgical treatment.

Diatoms in forensic analysis: A practical approach in rats

A diagnosis of drowning is a challenge in legal medicine, as there is generally a lack of pathognomonic findings indicative of drowning. Diatom analysis has been considered very supportive for a diagnosis of drowning, although the test is still controversial for some investigators. We assessed diatoms association with drowning in the peripheral tissues of drowned rats and the effects of the drowning medium on the diatom yield. A modified acid digestion method was optimised for diatom recovery in water and rat tissues. Eighteen adult Wistar rats were employed for the study, subdivided into six groups of three rats. Groups 1, 3 and 5 were drowned in seawater, lake water, or river water respectively, while groups 2, 4 and 6 were controls (immersed after death in seawater, lake water or river water respectively). Water samples were taken from the sea, lake and river in Málaga and Córdoba (Spain) for the purposes of diatomological mapping and drowning of the rats. Diatoms were successfully recovered from all water samples and matched with tissues of the drowned rats. There were significant differences in diatom numbers between control and test samples for all the tissues studied, as well as within test samples. Histological investigations conducted on lung samples obtained from drowned rats provided complementary and valuable information. This study demonstrates the feasibility of the diatom test as a reliable method for the diagnosis of drowning, especially if adequate precautions are taken to avoid contamination, and if interpretation of the analysis is performed in light of other complementary investigations.

Giant Primary Neuroendocrine Neoplasms of the Liver: Report of 2 Cases With Molecular Characterization

Primary neuroendocrine neoplasms of the liver have occasionally been reported in the liver, though many reports do not convincingly exclude metastases. In this article, we report 2 “giant” hepatic neuroendocrine lesions without evidence of a primary elsewhere after clinical workup. One occurred in a 21-year-old male; the lesion was a large cell neuroendocrine carcinoma measuring 24 cm. The patient died of disease in 10 months. The other occurred in a 25-year-old patient, was 18 cm wide, and was diagnosed as a well-differentiated neuroendocrine tumor, World Health Organization grade 3. The patient died of disease after 30 months. Molecular testing demonstrated only the presence of TP53 mutations in common. These cases expand our knowledge of seemingly primary neuroendocrine neoplasms of the liver, in particular, giant cases measuring more than 8 cm. Guidelines for clinical workup and therapy for these lesions remain unclear, but future thorough workup of such cases is necessary for specific characterization.

Denervated muscle extract promotes recovery of muscle atrophy through activation of satellite cells. An experimental study

PURPOSE

The objective of the present study was to determine whether a denervated muscle extract (DmEx) could stimulate satellite cell response in denervated muscle.

METHODS

Wistar rats were divided into 4 groups: normal rats, normal rats treated with DmEx, denervated rats, and denervated rats treated with DmEx. The soleus muscles were examined using immunohistochemical techniques for proliferating cell nuclear antigen, desmin, and myogenic differentiation antigen (MyoD), and electron microscopy was used for analysis of the satellite cells.

RESULTS

The results indicate that while denervation causes activation of satellite cells, DmEx also induces myogenic differentiation of cells localized in the interstitial space and the formation of new muscle fibers. Although DmEx had a similar effect in nature on innervated and denervated muscles, this response was of greater magnitude in denervated vs. intact muscles.

CONCLUSION

Our study shows that treatment of denervated rats with DmEx potentiates the myogenic response in atrophic denervated muscles.

Ultrasonographic and Histological Correlation after Experimental Reconstruction of a Volumetric Muscle Loss Injury with Adipose Tissue

Different types of scaffolds are used to reconstruct muscle volume loss injuries. In this experimental study, we correlated ultrasound observations with histological findings in a muscle volume loss injury reconstructed with autologous adipose tissue. The outcome is compared with decellularized and porous matrix implants. Autologous adipose tissue, decellularized matrix, and a porous collagen matrix were implanted in volumetric muscle loss (VML) injuries generated on the anterior tibial muscles of Wistar rats. Sixty days after implantation, ultrasound findings were compared with histological and histomorphometric analysis. The muscles with an autologous adipose tissue implant exhibited an ultrasound pattern that was quite similar to that of the regenerative control muscles. From a histological point of view, the defects had been occupied by newly formed muscle tissue with certain structural abnormalities that would explain the differences between the ultrasound patterns of the normal control muscles and the regenerated ones. While the decellularized muscle matrix implant resulted in fibrosis and an inflammatory response, the porous collagen matrix implant was replaced by regenerative muscle fibers with neurogenic atrophy and fibrosis. In both cases, the ultrasound images reflected echogenic, echotextural, and vascular changes compatible with the histological findings of failed muscle regeneration. The ultrasound analysis confirmed the histological findings observed in the VML injuries reconstructed by autologous adipose tissue implantation. Ultrasound can be a useful tool for evaluating the structure of muscles reconstructed through tissue engineering.

Late Cardiac Pathology in Severe Covid-19. A Postmortem Series of 30 Patients

The role of SARS-CoV-2 as a direct cause in the cardiac lesions in patients with severe COVID-19 remains to be established. Our objective is to report the pathological findings in cardiac samples of 30 patients who died after a prolonged hospital stay due to Sars-Cov-2 infection. We performed macroscopic, histological and immunohistochemical analysis of the hearts of 30 patients; and detected Sars-Cov-2 RNA by RT-PCR in the cardiac tissue samples. The median age of our cohort was 69.5 years and 76.6% were male. The median time between symptoms onset and death was 36.5 days. The main comorbidities were arterial hypertension (13 patients, 43.3%), dyslipidemia (11 patients, 36.7%), cardiovascular conditions (8 patients, 26.7%), and obesity (8 patients, 26.7%). Cardiovascular conditions included ischemic cardiopathy in 4 patients (13.3%), hypertrophic cardiomyopathy in 2 patients (6.7%) and valve replacement and chronic heart failure in one patient each (3.3%). At autopsy, the most frequent histopathological findings were coronary artery atherosclerosis (8 patients, 26.7%), left ventricular hypertrophy (4 patients, 13.3%), chronic epicardial inflammation (3 patients, 10%) and adipose metaplasia (2 patients, 6.7%). Two patients showed focal myocarditis, one due to invasive aspergillosis. One additional patient showed senile amyloidosis. Sars-Cov-2 RNA was detected in the heart of only one out of 30 patients, who had the shortest disease evolution of the series (9 days). However, no relevant cardiac histological alterations were identified. In present series, cardiac pathology was only modest in most patients with severe COVID-19. At present, the contribution of a direct effect of SARS-CoV-2 on cardiac lesions remains to be established.

Tumour size in adrenal tumours: its importance in the indication of adrenalectomy and in surgical outcomes-a single-centre experience

OBJECTIVE

To evaluate the relevance of tumour size in adrenal tumours in the estimation of malignancy risk and in the outcomes of adrenalectomy.

METHODS

We evaluate the histological results and surgical outcomes (intraoperative and postsurgical complications) in a retrospective single-centre cohort of patients without history of active extraadrenal malignancy with adrenal tumours consecutively operated in our centre during January 2010 and December 2020. We compared these results in lesions smaller and larger than 40, 50, and 60 mm.

RESULTS

Of 131 patients with adrenal tumours who underwent adrenalectomy, 76 (58.0%) had adrenal masses measuring ≥ 40 mm; 47 were > 50 mm and 28 > 60 mm. The final diagnosis was adrenocortical carcinoma (ACC) in 7 patients, pheochromocytoma in 35, and benign lesions in the remaining. All patients with ACC had adrenal masses > 50 mm, with Hounsfield units > 40 and low lipidic content in the CT. The risk of ACC and pheochromocytoma increased as tumour size did. The diagnostic accuracy of tumour size was quite good for the prediction of ACC (AUC-ROC 0.883). Nevertheless, when only adrenal tumours with HU < 40 were considered, the risk of ACC was 0% independent of tumour size. For pheochromocytomas, the risk was of 8.6% independent of tumour size for lesions with < 20HU. The risk of intraoperative and postoperative complications was independent of tumour size.

CONCLUSION

Risk of malignancy and of pheochromocytoma increased as tumour size increased, but, in the presurgical estimation of malignancy risk and of pheochromocytoma, not only tumour size, also lipidic content and other radiological features, should be considered. The risk of complications was independent of tumour size, but hospital stay was longer in patients with complication or open approach.

Molecular Heterogeneity of High Grade Colorectal Adenocarcinoma

Simple Summary

Due to its low frequency, high grade colorectal carcinomas (HG-CRCs) are underrepresented in molecular series. We intended to further characterize the pathological and molecular features of these tumors. In addition, morphologically different areas when present, were analyzed separately to study tumor heterogeneity. We found that most (72.5%) of HG-CRCs showed mismatch repair (MMR) deficiency. MMR status conditioned the frequency and the clonality of the molecular alterations found. Thus, whereas BRAF mutations and gene fusions were observed only in MMR deficient (MMRd) tumors, TP53, KRAS, and gene amplifications predominated in MMR proficient (MMRp) tumors. In MMRp tumors, gene amplification was a mechanism of progression, whereas the accumulation of mutations in genes of different pathways such as NOTCH, MMR or PIK3CA was involved in the clonal diversity of MMRd HG-CRC. In summary, intertumor and intratumor molecular heterogeneity in HG-CRCs is mainly due to MMR status.

Abstract

High grade colorectal carcinomas (HG-CRCs), which comprise 15% of colorectal carcinomas, are underrepresented in reported molecular studies. Clinicopathological, immunohistochemical, and molecular features of 40 HG-CRCs are described. Moreover, glandular and solid areas of 25 tumors were separately analyzed. The expression of MLH1, PMS2, MSH2, MSH6, p53, E-cadherin, CDX2, CK20, CD8, PDL1, PAN-TRK, c-MET, SMARCB1, ARID1A, SMARCA2, and SMARCA4 was analyzed by immunohistochemistry. Promoter MLH1 methylation was analyzed in tumors with MLH1/PMS2 loss. Next-generation sequencing was used to screen 161 genes for hotspot mutations, copy number variations and gene fusions. In this series, 72.5% of HG-CRCs showed mismatch repair deficiency (MMRd). MMR deficient tumor and MMR proficient (MMRp) tumors showed striking molecular differences. Thus, whereas BRAF mutations were only observed in MMRd tumors, mutations in KRAS and TP53 were more frequent in MMR proficient tumors. Moreover, gene fusions (NTRK1 and MET) were detected only in MMRd tumors, whereas gene amplification (MYC, CCND1 and EGFR) predominated in MMRp/TP53-mutated tumors. Loss of expression of proteins involved in chromatin remodeling, such as ARID1A, was observed only in MMRd HG-CRCs, which also showed more frequently PD-L1 expression and a higher number of tumor infiltrating lymphocytes. The separate analysis of glandular and solid areas indicated that the clonal or subclonal nature of the molecular alterations also depended on MMR status. Mutations in genes such as TP53 and KRAS were always clonal in MMRp-CRCs but occurred as subclonal events in MMRd-CRCs. Gene amplification was implicated in the progression of MMRp tumors, but not in MMRd tumors, in which clonal diversity was due to accumulation of mutations in genes of different pathways such as NOTCH, MMR, or PIK3CA. In summary, intertumor and intratumor molecular heterogeneity in HG-CRCs is mainly due to MMR status.

Transcranial Magnetic Stimulation Improves Muscle Involvement in Experimental Autoimmune Encephalomyelitis

Skeletal muscle is affected in experimental autoimmune encephalomyelitis (EAE), which is a model of multiple sclerosis that produces changes including muscle atrophy; histological features of neurogenic involvement, and increased oxidative stress. In this study, we aimed to evaluate the therapeutic effects of transcranial magnetic stimulation (TMS) on the involvement of rat skeletal muscle and to compare them with those produced by natalizumab (NTZ). EAE was induced by injecting myelin oligodendrocyte glycoprotein (MOG) into Dark Agouti rats. Both treatments, NTZ and TMS, were implemented from day 15 to day 35. Clinical severity was studied, and after sacrifice, the soleus and extensor digitorum longus muscles were extracted for subsequent histological and biochemical analysis. The treatment with TMS and NTZ had a beneficial effect on muscle involvement in the EAE model. There was a clinical improvement in functional motor deficits, atrophy was attenuated, neurogenic muscle lesions were reduced, and the level of oxidative stress biomarkers was lower in both treatment groups. Compared to NTZ, the best response was obtained with TMS for all the parameters analyzed. The myoprotective effect of TMS was higher than that of NTZ. Thus, the use of TMS may be an effective strategy to reduce muscle involvement in multiple sclerosis.

Prognosis Stratification Tools in Early-Stage Endometrial Cancer: Could We Improve Their Accuracy?

There are three prognostic stratification tools used for endometrial cancer: ESMO-ESGO-ESTRO 2016, ProMisE, and ESGO-ESTRO-ESP 2020. However, these methods are not sufficiently accurate to address prognosis. The aim of this study was to investigate whether the integration of molecular classification and other biomarkers could be used to improve the prognosis stratification in early-stage endometrial cancer. Relapse-free and overall survival of each classifier were analyzed, and the c-index was employed to assess accuracy. Other biomarkers were explored to improve the precision of risk classifiers. We analyzed 293 patients. A comparison between the three classifiers showed an improved accuracy in ESGO-ESTRO-ESP 2020 when RFS was evaluated (c-index = 0.78), although we did not find broad differences between intermediate prognostic groups. Prognosis of these patients was better stratified with the incorporation of CTNNB1 status to the 2020 classifier (c-index 0.81), with statistically significant and clinically relevant differences in 5-year RFS: 93.9% for low risk, 79.1% for intermediate merged group/CTNNB1 wild type, and 42.7% for high risk (including patients with CTNNB1 mutation). The incorporation of molecular classification in risk stratification resulted in better discriminatory capability, which could be improved even further with the addition of CTNNB1 mutational evaluation.

Muscular hypertrophy and atrophy in normal rats provoked by the administration of normal and denervated muscle extracts

This study was conducted to determine the effects of extracts obtained from both normal and denervated muscles on different muscle types. Wistar rats were used and were divided into a control group and four experimental groups. Each experimental group was treated intraperitoneally during 10 consecutive days with a different extract. These extracts were obtained from normal soleus muscle, denervated soleus, normal extensor digitorum longus, and denervated extensor digitorum longus. Following treatment, the soleus and extensor digitorum longus muscles were obtained for study under optic and transmission electron microscope; morphometric parameters and myogenic responses were also analyzed. The results demonstrated that the treatment with normal soleus muscle and denervated soleus muscle extracts provoked hypertrophy and increased myogenic activity. In contrast, treatment with extracts from the normal and denervated EDL had a different effect depending on the muscle analyzed. In the soleus muscle it provoked hypertrophy of type I fibers and increased myogenic activity, while in the extensor digitorum longus atrophy of the type II fibers was observed without changes in myogenic activity. This suggests that the muscular responses of atrophy and hypertrophy may depend on different factors related to the muscle type which could be related to innervation.

Lymphoglandular Complex-Like Colorectal Carcinoma-A Series of 20 Colorectal Cases, Including Newly Reported Features of Malignant Behavior

Distinguishing colon carcinoma that is surrounded by well-circumscribed lymphoid tissue from adenomas involving lymphoglandular complexes can be difficult. We assessed a multi-institutional international cohort of 20 colorectal carcinomas with associated prominent lymphoid infiltrates, which we referred to as lymphoglandular complex-like carcinoma (LGCC). We collected clinical and endoscopic features, including lesion size, endoscopic appearance, location, procedure, follow-up, AJCC stage, and mismatch repair status. We recorded the presence of the following histologic features: haphazard gland distribution, gland angulation, gland fusion, solid nest formation, single-cell formation, stromal desmoplasia, presence of lymphovascular invasion and perineural invasion, presence of lamina propria, cytologic atypia as low- or high-grade, presence of goblet cells in the invasive component, and the presence of a surface lesion. Most cases (9 of 13) were described endoscopically as sessile polyps with an average size of 1.56 cm. Most cases (90%) were associated with a surface lesion, of which the majority were tubular adenomas, though a subset was associated with sessile serrated lesions with dysplasia (3 of 18). All cases of LGCC demonstrated haphazard gland distribution and either gland angulation, fusion, or solid nest formation. A portion of cases demonstrated single-cell infiltration (35%) and desmoplasia (50%), and rarely lymphovascular invasion was present (5%). A subset (10%) of cases invaded beyond the submucosa. Deficient mismatch repair was present in 22% (2 of 9) of cases for which it was performed. In cases of colectomy or completion colectomy, nodal metastasis was present in 38% (3 of 8). No cases demonstrated disease recurrence or disease-specific mortality. Overall, LGCC represents an enigmatic subset of carcinomas that is important to distinguish from adenomas involving lymphoglandular complexes due to its varying prognostic outcomes.

IgG4-related disease in a patient with HIV infection

A 47-year-old HIV-positive man with good immune and virological status presented with chronic multiple enlarged lymph nodes, lung disease and eosinophilia. Radiologic tests showed enlarged cervical, thoracic and axillary lymph nodes, with interstitial lung damage. After several non-specific histologic studies, an elevated serum IgG4 level led us to request immunohistochemistry of a lymph node sample. The test confirmed the diagnosis of IgG4-related disease.

Histology of skeletal muscle reconstructed by means of the implantation of autologous adipose tissue: an experimental study

The purpose of this study was to determine the histological characteristics of a skeletal muscle reconstructed by means of the implantation of autologous adipose tissue following an experimentally-induced volumetric muscle loss. A cylindrical piece in the belly of the rat anterior tibial muscle was removed. In the hole, inguinal subcutaneous adipose tissue of the same rat was grafted. Animals were sacrificed 7, 14, 21, 28 and 60 days posttransplantation. Histological, histochemical, immunohistochemical and morphometric techniques were used. At all times analyzed, the regenerative muscle fibers formed from the edges of the muscle tissue showed histological, histochemical and immunohistochemical differences in comparison with the control group. These differences are related to delays in the maturation process and are related to problems in reinnervation and disorientation of muscle fibers. The stains for MyoD and desmin showed that some myoblasts and myotubes seem to derive from the transplanted adipose tissue. After 60 days, the transplant area was 20% occupied by fibrosis and by 80% skeletal muscle. However, the neo-muscle was chaotically organized showing muscle fiber disorientation and centronucleated fibers with irregular shape and size. Our results support the hypothesis that, at least from a morphological point of view, autologous adipose tissue transplantation favors reconstruction following a volumetric loss of skeletal muscle by combining the inherent regenerative response of the organ itself and the myogenic differentiation of the stem cells present in the adipose tissue. However, in our study, the formed neo-muscle exhibited histological differences in comparison with the normal skeletal muscle.

Structural abnormalities in the human diaphragm in drowning and hanging deaths: preliminary results

PURPOSE

Previous experiments in rats have indicated that there are histological changes in skeletal muscle in drowning deaths; these changes include muscle fibers that contain ragged red fibers (RRF). The purpose of this study was to examine whether these changes also occur in humans.

METHODS

Histologic and histochemical examinations of three muscles (diaphragm, pectoralis, and psoas) were performed on 24 cadavers with three different causes of death: 8 drowning, 8 hanging, and 8 sudden cardiac disease. Muscle samples were stained with hematoxylin-eosin, MGT, nicotinamide adenine dinucleotide-tetrazolium reductase, succinate dehydrogenase, ATPase, and acid phosphatase via standard staining procedures.

RESULTS

There were statistically significant differences in the detection of RRFs in these cohorts. Additionally, several other cytoarchitectural changes (whorled and core-like fibers) were observed in the diaphragm in the drowning cohort and to a lesser extent in the hangings. These structural abnormalities were not observed in the sudden cardiac disease deaths, thus suggesting a common mechanism for the production of these muscular changes that is not shared in the cardiac death group. The mechanism is most likely intense hypoxia and mechanical trauma of the respiratory muscles in the setting of active blood circulation with intense muscle contraction.

CONCLUSIONS

Our results confirmed that there are histological changes in the diaphragm in drownings and, to a lesser extent, in hangings.