Immunohistochemistry (IHC) and polymerase chain reaction (PCR) and fragment separation by capillary electrophoresis represent the current clinical laboratory standard for the evaluation of microsatellite instability (MSI) status. The importance of reporting MSI status in colorectal cancer is based on its potential for guiding treatment and as a prognostic indicator. It is also used to identify patients for Lynch syndrome testing. Our aim was to evaluate pre-analytical factors, such as age of formalin-fixed and paraffin-embedded (FFPE) block, neoplastic cell percentage, mucinous component, and DNA integrity, that may influence the accuracy of MSI testing and assess the concordance between three different MSI evaluation approaches. We selected the mucinous colorectal cancer (CRC) histotype for this study as it may possibly represent an intrinsic diagnostic issue due to its low tumor cellularity. Seventy-five cases of mucinous CRC and corresponding normal colon tissue samples were retrospectively selected. MMR proteins were evaluated by IHC. After DNA quality and quantity evaluation, the Idylla™ and TapeStation 4200 platforms were adopted for the evaluation of MSI status. Seventy-three (97.3%) cases were successfully analyzed by the three methodologies. Overall, the Idylla™ platform showed a concordance rate with IHC of 98.0% for microsatellite stable (MSS)/proficient MMR (pMMR) cases and 81.8% for MSI/deficient MMR (dMMR) cases. The TapeStation 4200 system showed a concordance rate with IHC of 96.0% for MSS/pMMR cases and 45.4% for MSI/dMMR cases. The concordance rates of the TapeStation 4200 system with respect to the Idylla™ platform were 98.1% for MSS profile and 57.8% for MSI profile. Discordant cases were analyzed using the Titano MSI kit. Considering pre-analytical factors, no significant variation in concordance rate among IHC analyses and molecular systems was observed by considering the presence of an acellular mucus cut-off >50% of the tumor area, FFPE year preparation, and DNA concentration. Conversely, the Idylla™ platform showed a significant variation in concordance rate with the IHC approach by considering a neoplastic cell percentage >50% (p-value = 0.002), and the TapeStation 4200 system showed a significant variation in concordance rate with the IHC approach by considering a DNA integrity number (DIN) ≥4 as cut-off (p-value = 0.009). Our data pinpoint a central role of the pre-analytical phase in the diagnostic outcome of MSI testing in CRC.

The variety of placental morphological findings with SARS-CoV-2 maternal infections has raised the issue of poor agreement in histopathological evaluation. The aims of this study were: to describe the histopathological placental features of a large sample of SARS-CoV-2-positive women who gave birth in Italy during the COVID-19 pandemic, to analyse the factors underlying these lesions, and to analyse the impact of placental impairment on perinatal outcomes. From 25 February 2020 to 30 June 2021, experienced perinatal pathologists examined 975 placentas of SARS-CoV-2-positive mothers enrolled in a national prospective study, adopting the Amsterdam Consensus Statement protocol. The main results included the absence of specific pathological findings for SARS-CoV-2 infections, even though a high proportion of placentas showed signs of inflammation, possibly related to a cytokine storm induced by the virus, without significant perinatal consequences. Further research is needed to better define the clinical implications of placental morphology in SARS-CoV-2 infections, but the results of this large cohort suggest that placentas do not seem to be a preferential target for the new Coronavirus infection.

There is a recent debate on the "transplantability" of ECD (Expanded Criteria Donors) kidneys and the selection criteria used to allocate them to single or double transplantation. Remuzzi et al. have defined a protocol incorporating pre-transplant donor biopsy to guide the use of older donor organs. They allocated organs as single or double transplants on the basis of histological findings. We aim to show the pros and cons of the only histological evaluation in the allocation of ECD kidneys, to compare the different experiences in United States and Europe and thus to discuss whether this tool should be used alone or included in a comprehensive clinical and histopathological evaluation. In the United States many Authors stated that the biopsy actually increases the percentage of kidney discarded and they raised questions about the importance of the biopsy in evaluating ECD kidneys for transplantation. On the other hand, the experiences of the majority of european transplant centers showed that allocating kidneys as single or dual transplant based on biopsy findings may achieve good graft and patient outcomes. Moreover, the experience of some centers as ours showed that kidneys allocated as DKT (Dual Kidney Transplant) on the basis of Remuzzi’s score could have been suitable for single transplantation suggesting the need of an adjustment of the Remuzzi Score System. Many Authors, who are in favor of histological evaluation, actually believe that a comprehensive clinical and histopathological assessment before transplantation remains necessary. We lack precise national- or international-based selection criteria to guide clinicians. An adjustment of the Remuzzi Score System could be taken into consideration such as narrowing the indication for DKT from those ECD kidneys with higher scores and including the histological evaluation in a multifactor score.

Antiphospholipid Antibody Syndrome (APS) is a systemic autoimmune disease characterized by acquired hypercoagulability with the possible development of venous, arterial, and microvascular thrombosis. We report a rare case of Libman–Sacks tricuspid valve endocarditis in a 38-year-old pregnant woman at 15 weeks gestation with unknown primary antiphospholipid syndrome. During a routine cardiac examination and echocardiography performed for a previous episode of pleuropericarditis, a large, mobile mass with irregular edges was found at the level of the tricuspid valve. Three main differential diagnoses for intramyocardial mass were examined: tumor, infective endocarditis, and nonbacterial thrombotic endocarditis (NTBE). Cardiac magnetic resonance imaging (CMR) with contrast raised the suspicion of a thrombus. The woman was hospitalized urgently at the Cardiac Intensive Care Unit of the Federico II University Hospital, and anticoagulant and antiplatelet therapy were started. The thrombophilic screening performed and medical history confirmed the diagnosis of primary antibody syndrome (APS). A multidisciplinary consultation with obstetricians, cardiologists, anesthetists, and cardiac surgeons was required. The patient decided not to terminate the pregnancy despite the risk to her health and to undergo cardiac surgery during pregnancy. Histological examination confirmed the presence of nonbacterial thrombotic endocarditis. Weekly obstetric scans were performed after surgery to verify fetal well-being. An emergency cesarean section was performed at the 35th week of gestation due to repeated deceleration and abnormal short-term variability on c-CTG in a pregnancy complicated by fetal growth restriction and gestational hypertension. A newborn weighing 1290 g was born. She was hospitalized in Neonatal Intensive Care and discharged after two months; currently, she enjoys good health. The management of patients with antiphospholipid antibody syndrome has not yet been standardized, but there is a general consensus that patients who do not have thrombocytopenia, thromboembolic phenomena, or pregnancy should not undergo any treatment or should take only low doses of acetylsalicylic acid. In the presence of any of the above conditions, various treatment regimens have been used based on the severity and individuality of the case.

The aim of this study was, firstly, to analyze the histopathological characteristics of placentas in women with uneventful pregnancies and affected by COVID-19 at the time of delivery; and secondly, to correlate histological findings to maternal and neonatal characteristics. In our single-center prospective observational study, 46 placentas from term uncomplicated singleton pregnancies of patients with a documented SARS-CoV-2 infection at the time of delivery underwent histological examination. Despite a normal feto-maternal outcome, most of the placentas (82.6%) presented signs of maternal vascular malperfusion, while features of fetal vascular malperfusion were found in 54% of cases. No correlation was detected between maternal and neonatal characteristics and the severity of blood circulation disease, and abnormal findings were also described in asymptomatic patients. Moreover, we did not find any maternal symptoms or clinical details allowing for the prediction of abnormal placental findings in pregnancy complicated by COVID-19 infection. Our results suggest that SARS-CoV-2 infection during pregnancy could lead to acute placental dysfunction.

Background: Tailgut cysts are rare congenital lesions that develop in the presacral space. As they can potentially conceal primary neuroendocrine tumors, surgical excision is suggested as the treatment of choice. However, specific management guidelines have yet to be developed. A posterior approach is usually preferred for cysts extending to the third sacral vertebral body. Conversely, a transabdominal approach is preferred for lesions extending upward to achieve an optimal view of the surgical field and avoid injuries. Case report: Here, we report a case of a 48-year-old man suffering from perianal pain and constipation. Digital rectal examination and magnetic resonance imaging revealed a presacral mass below the third sacral vertebral body. A laparoscopic transabdominal presacral tumor excision was performed. The final histological diagnosis was a rare primary neuroendocrine tumor arising from a tailgut cyst. The postoperative course was uneventful, and no signs of recurrence were observed at the six-month follow-up. Conclusions: This study may help establish more well-grounded recommendations for the surgical management of rectal tumors, demonstrating that the laparoscopic transabdominal technique is safe and feasible, even for lesions below the third sacral vertebral body. This approach provided an adequate view of the presacral space, facilitating the preservation of cyst integrity, which is essential in cases of malignant pathologies.