Permanent Sections Research Articles

A comparative study of intraoperative frozen section and alpha defensin lateral flow test in the diagnosis of periprosthetic joint infection

Background and purpose — For decision-making (aseptic vs. septic), surgeons rely on intraoperatively available tests when a periprosthetic joint infection (PJI) cannot be confirmed or excluded preoperatively. We compared and evaluated the intraoperative performances of the frozen section and the alpha defensin lateral flow test in the diagnosis of PJI.Patients and methods — In this prospective study, consecutive patients with indicated revision surgery after arthroplasty were included. Patients were classified as having PJI using the MusculoSkeletal Infection criteria. The presence of alpha defensin was determined using the lateral flow test intraoperatively. During revision surgery, tissue samples were harvested for frozen and permanent section. Analysis of diagnostic accuracy was based on receiver-operating characteristics.Results — 101 patients (53 hips, 48 knees) were eligible for inclusion. Postoperatively, 29/101 patients were diagnosed with PJI, of which 8/29 cases were definitely classified as septic preoperatively. Of the remainder 21 septic cases, the intraoperative alpha defensin test and frozen section were positive in 13 and 17 patients, respectively. Sensitivities of the alpha defensin test and frozen section were 69% and 86%, respectively. The area under the curves of both tests showed a statistically significant difference (p = 0.006).Interpretation — The frozen section showed a significantly higher performance compared with the alpha defensin test and a near perfect concordance with the definitive histology, and therefore remains an appropriate intraoperative screening test in diagnosing PJI. Although the sensitivity of the alpha defensin test was lower compared with that of frozen section, this test is highly specific for confirming the diagnosis of PJI.

Sensitivity and specificity of frozen section diagnosis in orbital and adnexal malignancies.

Purpose:To analyze the diagnostic accuracy of frozen section in orbital and adnexal malignancies.Methods:A total of 55 cases between January 2006 and December 2011 for which intraoperative frozen section was performed for various orbital and adnexal lesions were included in the study. The frozen section diagnosis was compared with the permanent section diagnosis. Margin clearance was also compared between the two. Data were analysed using SPSS version 14. Odds ratio and cross-tabulation was used to perform the analysis.Results:The mean age at presentation was 51.46 ± 20 years. Eyelid was the most common site of involvement. Out of 55 cases, diagnosis was deferred in four cases (7.27%) on frozen section. Among 51 cases, 44 (86%) cases were concordant, whereas 7 (13%) cases were discordant. The sensitivity and specificity of frozen section compared to permanent section for diagnosis of malignancy was found to be 87.2% and 87.5%, respectively. The sensitivity and specificity of frozen section for diagnoses of basal cell carcinoma was found to be 100%, while it was 83.3% and 100% respectively for sebaceous gland carcinoma and 87.5% and 94.9% respectively for squamous cell carcinoma.Conclusion:Frozen section had high sensitivity and specificity when compared with permanent section for all three parameters studied. It is an important intraoperative tool that is increasingly being used in histopathological examination of ophthalmic lesions. However, it should not be used as a substitute for the permanent section and critical decisions based on it are best avoided.

Clinicopathological Characteristics of Hirschsprung's Disease With Emphasis on Diagnosis and Management: A Single-Center Study in the Kingdom of Saudi Arabia.

Introduction: Hirschsprung’s Disease (HD) is a motor disorder of the gut caused by the failure of neural crest cells to migrate craniocaudally into the bowel during intestinal development, resulting in a functional obstruction. The majority of patients with HD are diagnosed in the neonatal period when they present with symptoms of distal intestinal obstruction. Aim: This study aims to identify the clinic-pathological characteristic of HD patients in our institution in KSA and comparing it with local and international data. Materials and Methods: This retrospective cohort study was conducted in King Abdulaziz Medical City (KAMC), a tertiary care center in Riyadh, Kingdome of Saudi Arabia (KSA). Results: A total of 54 patients (72% male) were diagnosed with HD. Forty-eight patients (89%) were born at term, and 6 were pre-term. Sixty-three percent of the patients presented in the neonatal period. Twenty-two patients (41%) underwent one-stage endorectal pull-through procedure, 23 patients (43%) two-stage endorectal pull-through, and 9 patients (16%) had three-stage endorectal pull-through. Five out of 54 patients had ganglion cells seen on FS but were absent in the permanent section. Therefore, the concordance rate was 90.8%. Conclusion: FS biopsy is a necessary method to determine the level of aganglionosis intraoperatively in HD, but the definitive diagnosis should be with permanent section. Also, the choice of surgical operation type (single-stage or multi-stage pull-through) depends on the patient’s clinical condition.

Classic Markers for Infection Perform Poorly in Predicting Residual Infection Prior to Reimplantation.

Two-stage exchange arthroplasty remains the treatment of choice for chronic periprosthetic joint infections. This retrospective study conducted between 2009 and 2015 examined the diagnostic value of biomarkers for residual infection between stages. The biomarkers evaluated included C-reactive protein prior to reimplantation, preimplantation synovial fluid white blood cell count and percent neutrophils, and the intraoperative histologic synovial white blood cell count per high-power field (×400) on permanent sections. Residual infection was defined as either positive cultures (more than 1) at second stage, any further surgery (eg, amputation, arthrodesis, or another 2-stage revision), or the need for infection suppression with antibiotics. Sensitivity, specificity, positive and negative predictive values, and likelihood ratios were calculated accordingly. A total of 182 two-stage exchange operations that included 109 (59.9%) prosthetic hips and 73 (40.1%) prosthetic knees met the inclusion criteria. Residual infection was present in 38 (20.9%) of the procedures. The area under the curve-receiver operating characteristic values were 0.677 for C-reactive protein (P=.002), 0.506 for aspiration white blood cell count (P=.944), 0.623 for aspiration percent neutrophils (P=.200), and 0.524 for white blood cell count per high-power field (P=.801). Positive and negative predictive values were poor and ranged between 26% and 57% and 78% and 85%, respectively. Analyses using specific combinations of biomarkers did not significantly improve predictive values. This study showed that classic markers perform poorly in identifying residual infection prior to second-stage revision. Further research is necessary to evaluate the diagnostic utility of other, more recently introduced biomarkers to determine whether infection has been eradicated between stages. [Orthopedics. 2019; 42(1):34-40.].

Intramedullary spinal cord ependymoma and astrocytoma: intraoperative frozen-section diagnosis, extent of resection, and outcomes.

OBJECTIVEThe intraoperative differentiation of ependymomas from astrocytomas is important because neurosurgical strategies differ between these two tumor groups. Previous studies have reported that the diagnostic accuracy of intraoperative frozen sections of intracranial central nervous system (CNS) tumors is higher than 83%-97%, whereas that for spinal intramedullary tumors remains unknown. Herein, authors tested the hypothesis that intraoperative frozen-section diagnosis is the gold standard for a differential diagnosis of intramedullary spinal cord tumors.METHODSThe clinical characteristics, intraoperative histological diagnosis from frozen sections, extent of tumor resection, progression-free survival (PFS), and overall survival (OS) of 49 cases of intramedullary spinal cord ependymomas (n = 32) and astrocytomas (n = 17) were retrospectively evaluated.RESULTSThe frozen-section diagnosis and final diagnosis with permanent sections agreed in 23 (72%) of 32 cases of ependymoma. Of the 9 cases of ependymoma in which the frozen-section diagnosis disagreed with the final diagnosis, 4 were incorrectly diagnosed as astrocytoma and the other 5 cases had a nonspecific diagnosis, such as glioma. Nonetheless, gross-total resection was achieved in 6 of these 9 cases given the presence of a dissection plane. The frozen-section diagnosis and final diagnosis agreed in 12 (71%) of 17 cases of astrocytoma. Of the 5 cases of astrocytoma in which the frozen-section diagnosis disagreed with the final diagnosis, 1 was incorrectly diagnosed as ependymoma and the other 4 had a nonspecific diagnosis. Gross-total resection was achieved in only 1 of these 5 cases.A relationship between the size of tumor specimens and the diagnostic accuracy of frozen sections was not observed. Ependymal rosettes and perivascular pseudorosettes were observed in 30% and 57% of ependymomas, respectively, but were absent in astrocytomas.Progression-free survival and OS were both significantly longer in cases of ependymoma than in cases of astrocytoma (p < 0.001). Gross-total resection was achieved in 69% of ependymomas and was associated with longer PFS (p = 0.041). In the astrocytoma group, gross-total resection was achieved in only 12% and there was no relationship between extent of resection and OS. Tumor grades tended to correlate with OS in astrocytomas (p = 0.079).CONCLUSIONSThe diagnostic accuracy of intraoperative frozen sections was lower for intramedullary spinal cord ependymomas and astrocytomas in the present study than that for intracranial CNS tumors reported on in the literature. Surgical strategies need to be selected based on multiple factors, such as clinical characteristics, preoperative imaging, frozen-section diagnosis, and intraoperative findings of the tumor plane.

Malignant eyelid tumors: Are intra-operative rapid frozen section and permanent section diagnoses of surgical margins concordant?

To study the concordance between intra-operative rapid frozen section and permanent section diagnoses of surgical margins following wide surgical excisional biopsy of malignant eyelid tumors. This is a retrospective study of 120 cases and 429 frozen section slides. Of 120 cases, 75 (63%) had sebaceous gland carcinoma, 34 (28%) had basal cell carcinoma, and 11 (9%) had squamous cell carcinoma. All cases with these malignant eyelid tumors underwent wide surgical excisional biopsy under frozen section control of surgical margins. A total of 429 frozen section slides were reviewed for rapid frozen section diagnosis. Eyelid reconstruction was performed in all cases after clearance was obtained by rapid frozen section diagnosis of surgical margins as negative for tumor infiltration. Permanent section diagnosis of surgical margins was positive for tumor infiltration in 5 (1%) slides, which were reported as negative on rapid frozen section diagnosis of surgical margins, and was negative for tumor infiltration in 3 (< 1%), which were reported as positive on initial rapid frozen section diagnosis of surgical margins. The sensitivity, specificity, and accuracy of intra-operative rapid frozen section diagnosis of surgical margins for malignant eyelid tumors were 89%, 99%, and 98%, respectively. The concordance between the intra-operative rapid frozen section and permanent section diagnoses of surgical margins following wide surgical excisional biopsy of malignant eyelid tumors is excellent at 98%.

Frequent false-negative immunohistochemical staining with IDH1 (R132H)-specific H09 antibody on frozen section control slides: a potential pitfall in glioma diagnosis.

Intraoperative consultation using frozen sections (FSs) is an integral component of clinical practice. As a quality control measure, FS diagnosis is subsequently compared with the findings on a FS control slide. These control slides can be used for immunohistochemistry, and the immunohistochemical performance in FS controls is known to be antibody-dependent. Isocitrate dehydrogenase (IDH) is mutated in >80% of lower-grade infiltrating gliomas in adults and in ~10% of glioblastomas, with IDH1 (R132H) being the most common mutation. IDH status is used as a major classifier of glioma. An IDH1 (R132H)-specific antibody (H09) has been accepted as a robust surrogate for genetic testing. In this study, we aimed to determine how previous freezing and thawing affects IDH1 immunohistochemistry. Thirty cases of IDH1 (R132H)-mutant diffuse glioma, which were originally assessed on FSs, were retrieved. The positive IDH1 (R132H) status of each case was previously determined with pyrosequencing and H09 immunohistochemistry on permanent sections. The FS control tissue of each case was immunostained with H09 antibody. Among 30 gliomas, 25 showed negative reactivity on FS control slides, whereas, in the remaining five, the staining was uninterpretable, owing to a high diffuse background. Of the former 25 specimens, 20 showed at least focal areas with variably increased levels of background staining, whereas the remaining five specimens showed a relatively pristine background. We conclude that IDH1 (R132H)-specific (H09) immunohistochemistry often results in false-negative reactions on FS controls with focally increased background staining, and this application should be avoided in clinical practice.

What is Ideal Proximal Resection Margin in Carcinoma Stomach

Objective: The goal of cancer surgery is to achieve clear margins, where the surgeon resects the tumor along with normal adjacent tissue and pathologist confirms the absence of cancer cells of the margin of this resected tissue. Complete resection with negative surgical margins along with lymph node dissection has been accepted as the only possible curative treatment for gastric cancer. Although there have been several studies on the sufficient length of margins that guarantees tumor-free resection and prevents local recurrences, definite consensus has not yet been reached, especially about the proximal resection margin (PRM).&#x0D; Methods: The study was conducted in the Department of General Surgery, Sher I Kashmir Institute of Medical Sciences, Soura, Srinagar, Jammu and Kashmir, India between September 2011 and September 20013 and a total of 115 patients of ca stomach were included in the study. PRM of resected specimen was undertaken at 0.5cm, 1cm, 1.5cm, 2cm, 2.5cm, 3cm, 3.5cm, 4cm, 5cm and 6cm. A resection margin was considered positive if permanent section examination revealed tumor tissue at the line of transaction. The relation between infiltration of margins and various parameters of tumor-like location, size, histological type and depth of invasion into gastric wall was determined. The difference in the distribution and rate of margin infiltration was statistically evaluated, and a probability equal to or less than 0.05 was accepted as significant.&#x0D; Results: Out of 115 patients of ca stomach who underwent partial or total gastrectomy, proximal margin infiltration was seen in 5 patients (4.35%). No infiltration of proximal margin was seen when the length of the resected margin was &gt;50mm. Margin infiltration was commonly found in tumors located at upper third, in diffuse histological type and with lymph node metastasis.&#x0D; Conclusion: Since tumor infiltration at resection lines has been accepted as an adverse prognostic factor, negative resection margin are crucial components of curative surgery. Achieving a negative resection margin is the ultimate goal when determining the adequate length for PRM. In our study, we found that a PRM of greater than 5 cm is ideal for having a negative resection margin for all grades, sizes and T &amp; N stages of carcinoma stomach. JMS 2018;21(1):31-36

Pathologic analyses of peritoneal nodules in gastric cancer patients during surgery—A single cancer center experience with diagnostic pitfalls

Background: Gastric carcinoma (GC) is the second most common cause of cancer-related deaths worldwide. During operations, nodular lesions of the peritoneum are often sent for frozen section (FS). For pathologists, FS of the peritoneum is challenging due to sparse and discohesive tumor cells in a fibrotic background.Methods: To explore diagnostic accuracy and diagnostic pitfalls of FS in this setting, we retrospectively collected 252 peritoneal biopsies in cases with GC from January 2006 to May 2017 and compared corresponding permanent sections and patient prognosis. After review, 6 cases (2.4%) were discrepant: positive conversion was identified in 5 cases due to scarce tumor cells associated with severe fibrosis and inflammation; negative conversion was identified in one case due to papillary mesothelial cell proliferation masquerading as carcinoma.Results: Two hundred cases were finally confirmed as positive for tumor cells. Of these, 185 (92.5%) patients died of GC, with survival times ranging from 7 to 3574 (mean 415) days after operation. Fifty-two (20.6%) cases were negative for tumor, and pathologic findings included chronic inflammation with fibrosis (N = 25: associated with previous operation, 10; idiopathic, 15) and papillary mesothelial cell proliferation (N = 9). All 5 patients with frozen diagnosis converted to positive results died of GC during follow up. A total of 19 patients with peritoneal nodules diagnosed as benign on FS died with GC (79.0%), and their survival times ranged from 87 to 3649 (mean 833) days.Conclusions: Peritoneal biopsies in patients with GC were mostly carcinoma, followed by chronic inflammation with fibrosis and papillary mesothelial cell proliferation. Deeper sections or intradepartmental consultations were helpful to reduce false negative diagnosis on FS.

Evaluation of a micro-spectrometer for the real-time assessment of liver graft with mild-to-moderate macrosteatosis: A proof of concept study

Liver macrosteatosis (MS) is a major predictor of graft dysfunction after transplantation. However, frozen section techniques to quantify steatosis are often unavailable in the context of procurements, and the findings of preoperative imaging techniques correlate poorly with those of permanent sections, so that the surgeon is ultimately responsible for the decision. Our aim was to assess the accuracy of a non-invasive pocket-sized micro-spectrometer (PSM) for the real-time estimation of MS. We prospectively evaluated a commercial PSM by scanning the liver capsule. A double pathological quantification of MS was performed on permanent sections. Initial calibration (training cohort) was performed on 35 livers (MS ≤60%) and an algorithm was created to correlate the estimated (PSM) and known (pathological) MS values. A second assessment (validation cohort) was then performed on 154 grafts. Our algorithm achieved a coefficient of determination R2 = 0.81. Its validation on the second cohort demonstrated a Lin's concordance coefficient of 0.78. Accuracy reached 0.91%, with reproducibility of 86.3%. The sensitivity, specificity, positive and negative predictive values for MS ≥30% were 66.7%, 100%, 100% and 98%, respectively. The PSM could predict the absence (<30%)/presence (≥30%) of MS with a kappa coefficient of 0.79. Neither graft weight nor height, donor body mass index nor the CT-scan liver-to-spleen attenuation ratio could accurately predict MS. We demonstrated that a PSM can reliably and reproducibly assess mild-to-moderate MS. Its low cost and the immediacy of results may offer considerable added-value decision support for surgeons. This tool could avoid the detrimental and prolonged ischaemia caused by the pathological examination of (potentially) marginal grafts. This device now needs to be assessed in the context of a large-scale multicentre study. Macro-vacuolar liver steatosis is a major prognostic factor for outcomes after liver transplantation. However, it is often difficult for logistical reasons to get this estimation during procurement. Therefore, we developed an algorithm for a commercial, portable and affordable spectrometer to accurately estimate this content in a real-time fashion. This device could be of great interest for clinical decision-making to accept or discard a potential human liver graft.

Growth hormone-secreting pituitary macroadenoma presenting concurrently with non-Hodgkin’s lymphoma and responding to doxorubicin treatment: case report and review of the literature

We present a case report of a patient who presented with nausea and vomiting, as well as acromegalic features. Following testing, a pituitary adenoma and mediastinal non-Hodgkin's lymphoma were diagnosed. Following two cycles of R-CHOP chemotherapy, imaging showed significant decrease in size of the sellar tumor. Following resection of tumor, both frozen and permanent section revealed only necrotic material. Further research into the potential utility of doxorubicin for the treatment of recurrent or refractory pituitary adenomas may be warranted.

Prospective Study of 3-Fraction Intra-Cavitary Accelerated Partial Breast Brachytherapy: Early Provider and Patient-Reported Outcomes of a Novel Regimen

The optimal dose and fractionation for accelerated partial breast irradiation (APBI) is not known. We evaluated 3-fraction brachytherapy APBI in the context of a prospective clinical trial. Our purpose is to report early adverse effects and patient-reported outcomes (PROs) of this novel regimen. Eligible women were ≥ 50 years of age with ≤2 cm estrogen receptor positive, sentinel lymph node (SLN) negative invasive or in-situ breast cancer treated with breast conserving surgery. After frozen section pathology assessment of negative surgical margins and SLN(s), a multi-channel intra-cavitary brachytherapy catheter was placed intraoperatively. APBI was initiated on the second weekday after surgery after permanent section pathology confirmation. The prescription was 21 Gy in 3, once daily, fractions targeting the lumpectomy cavity with a 1 cm expansion. Common toxicity criteria for adverse effects (CTCAE v 4.0), 10-point linear analog scales, PROs version of the CTCAE (PRO-CTCAE), and Harvard Breast Cosmesis Scale (HBCS) were utilized for provider and patient-reported assessments. Seventy-three women, median age 66 years, were treated for invasive breast cancer (79%) or ductal carcinoma in situ (21%) between 2015 and 2017. Tumor grade was 1-2 in 88%. The median time to completion of all locoregional therapy (surgery and radiotherapy) was 6 days. After 14 months median follow-up, two patients (3%) had developed breast infections that resolved with oral antibiotics. There was no other treatment-associated adverse effects ≥ grade 2. The grade 1 seroma rate at 3 months was 20% (11/56 evaluable patients) which dropped to 8% (4/49) at 12 months; none required intervention. PROs are summarized in table 1. At 12 months, 91% reported overall QOL between 8 and 10 and patient-reported cosmesis was good or excellent in 95%. All patients were alive without relapse at the last follow-up. The 3-fraction, once daily, breast brachytherapy was associated with favorable early physician and PROs. These early results compare favorably with other reports including the more universally employed twice daily (3.4 Gy x 10) fractionation being studied in NSABP B-39. A randomized trial comparing these two approaches is warranted.Abstract TU_5_3369; Table 1Patient-Reported Outcomes associated with 3-fraction brachytherapy APBIPROsLASA 10Baseline (n=56)Post-RT (n=51)3 month (n=44)6 month (n=46)12 month (n=35)Quality of Lifeα8-1095%96%89%96%91%4-74%2%7%2%9%1-31%2%4%2%0%Breast CosmesisExcellent55%41%50%65%69%Good45%49%39%26%26%Fair0%10%9%9%6%Poor0%0%2%0%0%Painβ0-361%69%86%91%86%4-632%22%7%4%9%7-107%10%7%4%6%Fatigueβ0-361%55%75%63%71%4-625%37%16%24%12%7-1014%8%9%13%17%Skin BurnsNone100%90%88%96%100%Mild0%8%12%2%0%Moderate0%0%0%0%0%Severe0%0%0%0%0%Very Severe0%2%0%2%0%LASAα: Reported on a scale of 1-10 (1 indicating “worst” and 10 indicating “best”) LASAβ: Reported on a scale of 1-10 (1 indicating “none” and 10 indicating “as bad as it can be”). Open table in a new tab

There Is High Sensitive and Specific Correlation Between Frozen and Permanent Sections in Renal Transplant Biopsies

IntroductionFrozen sections have been used for evaluating tumors and margins during daily practice in pathology with high specificity and sensitivity (>90% for both indices both at national level and in our department). The correlation between frozen section tissue for immunofluorescent (IF) studies and permanent sections for light microscopy, along with electron microscopy, is critical for constructing a final renal pathology diagnosis. MethodsWe studied the correlation between the frozen sections for IF studies and separate fragments of tissue for permanent light microscopic sections in our renal transplant biopsies for purposes of quality control. Frozen sections for IF sections were compared with permanent sections for light microscopy in 122 renal transplant biopsies, using inflammation as the key criterion (63 with no inflammation and 59 with inflammation) to determine the correlation. ResultsThere was high sensitivity (94.9%) and specificity (92.1%) for the correlation between the frozen section and permanent sections. ConclusionsOur data suggest that parts of renal transplant biopsy tissue dissected to freeze for IF studies and for light microscopy were highly correlated to ensure a high quality of renal tissue dissection for the final diagnosis in renal transplant biopsies.

FROZEN SECTION DIAGNOSIS: AN EXPERIENCE AT THE INSTITUTE (CHUGHTAI’S LAHORE LAB, LAHORE)

Background: Frozen section based histological diagnosis is required by the surgeon(s) to make immediate intraoperative decision(s) So, high accuracy of frozen section is important for the reporting surgical pathologist(s) and surgeon(s) to make subsequent on-table decision for the management of the patient.&#x0D; Objective: To assess the concordance of frozen section histological diagnosis reported in our institute by comparing it with subsequent final histological diagnosis.&#x0D; Material &amp; Methods: Biopsy specimens 100 patients submitted for frozen section diagnosis were included in the study. The diagnosis rendered on fresh frozen section was compared with the diagnosis rendered on paraffinembedded formalin-fixed section of the same specimen.&#x0D; Results: Male-to-female ratio of the patients included in the study was 2:1 with mean age of 48.70 years. The diagnosis could be rendered in 99 cases, while in 1 case diagnosis was deferred to permanent sections (deferral rate: 1%). There was no difference found between the frozen section diagnosis and the final diagnosis in 97 (concordance rate: 97.9%) cases.&#x0D; Conclusion: Frozen section-based histological assessment for diagnosis and/or surgical resection margins status is a reliable technique in terms of its timely and accurate reporting and low deferral rate.

Lentification in Alpine rivers: patterns of diatom assemblages and functional traits

Hydrological alterations in Alpine rivers have been largely increasing due to the combined effects of global climate change and local impacts. Water flow intermittency starts with a process called lentification, which leads to the transformation of the aquatic ecosystem with severe consequences on biotic communities. These consequences have a greater impact in Alpine headwater streams, which are considered important and fragile hotspots of biodiversity and a source of threatened species; the new regime creates conditions to which native biota are poorly adapted. The main aim of our work was to evaluate taxonomical, functional and structural changes of diatom communities in Alpine rivers during the lentification process that precedes a supra-seasonal drought. Contrary to what was expected, communities exposed to river shrinking showed a level of homogeneity comparable to those collected in permanent sections. We therefore hypothesized that lentification created an intermediate disturbance that favoured heterogeneity of assemblages. Conversely, ecological guilds, growth forms and eco-morphological groups varied along temporal and spatial gradients driven by the lentification process. Small, motile and medium-sized low profile species were more abundant during summer, as well as adnate and stalked ones. Lentification limited the presence of high profile guilds and mucous-forming colonies. Droughts in Alpine streams are fairly recent processes, and the dynamics of aquatic communities facing water scarcity are largely unknown. The results we obtained provide important insights towards a more refined functional classification of diatoms for evaluating hydrological alterations.

Nipple-Sparing Mastectomy: Reliability of sub-areolar sampling and frozen section in predicting occult nipple involvement in breast cancer patients

IntroductionThe oncological safety of nipple-areolar complex (NAC) preservation is a concern in the mastectomies performed for cancer indication. The detection of tumor cells during the intraoperative frozen section examination (IE) of sub-areolar/nipple tissue (SAT) leads to the removal of NAC, but frequently the final histology of the nipple is negative for malignancy. This study aims to evaluate the accuracy of SAT examination in predicting occult NAC involvement in case of Nipple-Sparing Mastectomy (NSM). MethodsThe study includes 76 NSM. We evaluated the concordance between histopathologic features of frozen and paraffin-embedded SAT sections. Moreover, we examined the "true margin" (TM), defined as the measurement of the distance between the tumor margin and the edge of the SAT. A margin >1 mm was considered negative. ResultsIn 26/76 cases the IE of the SAT was positive. At the final histology, the NAC was negative in 57.7% of cases. The concordance between frozen and paraffin section examination of the SAT was 92.1%. The three false-positives were low-grade DCIS at the IE, and negative or DIN1a on permanent section. A negative TM seems to predict for a negative NAC (6/6). ConclusionsThe detection of a low-grade DCIS at the IE of the SAT may not be confirmed at the permanent section examination; we recommend caution in removing the NAC in these cases. The evaluation of the TM may improve the accuracy of SAT analysis in predicting occult NAC involvement; in our series, a TM wider than 1 mm correlates with a negative NAC.

Anatomy and Surgical Approach of the Ear and Temporal Bone.

The temporal bone is one of the more complex structures at the skull base that houses the hearing and vestibular organs, numerous nerves, and vessels. A host of inflammatory and neoplastic processes can occur within the temporal bone that often necessitate permanent and frozen section pathologic examination. A number of simple to complex surgical procedures are used to manage temporal bone pathology. This chapter will provide a brief overview of normal temporal bone anatomy, common surgical approaches, normal histology, and indications for pathologic examination.

Frozen Section in the Management of Ovarian and Uterine Tumors: The Past 5 Years in a Tertiary Centre.

Intraoperative frozen section (IFS) is a valuable resource, and its use in gynecological pathology has not been sufficiently emphasized. The main goal of the present study is to evaluate the reliability and agreement rates between IFS and the final paraffin section (PS) and determine how reliable IFS is. A retrospective study of all IFSs performed on uterine tumors and suspicious adnexal masses between January 2012 and December 2016 (excluding metastases) at the department of obstetrics and gynecology of the Centro Hospitalar Tondela Viseu. Frozen versus permanent section diagnosis were compared regarding the histologic type of the tumor, and the depth of myometrial invasion. A total of 286 cases were eligible for the present study, including 102 (35.7%) IFSs of uterine tumors, and 184 (64.3%) IFSs of ovarian tumors. The overall rate of deferred cases was 5.2% (15/286). The accuracy of the diagnosis in cases of endometrial carcinoma was 96.25% (77/80). Among the ovarian tumors, misdiagnoses occurred in 2 cases (1.1%), corresponding to a borderline tumor (serous type) and a clear cell intracystic adenocarcinoma. The IFS analysis plays an important role in selected situations and is associated to a high sensitivity and specificity in cases of ovarian and endometrial tumors. Its high accuracy is almost universally associated with the possibility of obtaining an optimal surgical treatment at the time of the first surgical approach.

Evaluation of MITF, SOX10, MART-1, and R21 Immunostaining for the Diagnosis of Residual Melanoma In Situ on Chronically Sun-Damaged Skin.

Melanocytic immunostains can assist in margin evaluation of melanoma in situ (MIS) excisions; however, their accuracy and reliability relative to hematoxylin & eosin (H&E) is yet to be determined. The objective of this study was to evaluate the sensitivity, specificity, and concordance of 4 melanocyte-specific immunostains for diagnosing MIS occurring on chronically sun-damaged skin. Serial permanent sections from representative areas of negative margin and residual tumor were stained using H&E, MITF, MART-1, SOX10, and R21 and examined in a blinded fashion. The study set included 100 digital microscopy images from 10 cases of MIS excisions from the face. Two board-certified dermatopathologists, 4 fellowship-trained Mohs surgeons, 2 Mohs fellows, and 2 dermatology residents independently reviewed the 100 images. The average melanocyte density was 11 versus 28 melanocytes per 0.5 mm for chronically sun-damaged skin versus residual MIS on H&E, respectively. Statistically significantly higher melanocyte densities were observed using MITF, MART-1, and SOX10 on negative margins. The sensitivity and interobserver concordance was highest using MITF and SOX10. The intraobserver agreement on 4 duplicate images was 85%. In conclusion, the nuclear immunostains (MITF and SOX10) show the most promise for improving the diagnosis of MIS in chronically sun-damaged skin.

Oil Red O Is a Useful Tool to Assess Donor Liver Steatosis on Frozen Sections During Transplantation

Oil Red O is a useful tool to assess donor liver steatosis on frozen sections during transplantation.Steatosis is a frequent finding in liver evaluation during transplantation, accounting for 9% to 26% of biopsied donor liver. The degree of macrovesicular steatosis is classified as mild, moderate, and severe; the latter is considered an absolute contraindication to liver transplantation because it is associated with poor allograft outcome. Because of the scarcity of organs, there is a debate whether livers with less severe macrovesicular steatosis are still suitable for transplant. Consequently, tools or methods that allow a more accurate intraoperative assessment of steatosis on frozen sections are mandatory.The aim of this study is to improve intraoperative evaluation of steatosis during transplantation using Oil Red O stain on liver biopsies. MethodsTwenty consecutive liver biopsies of donors were collected during transplantation procedures from September 2017 to February 2018 at the Institute of Pathology of the University and Hospital Trust of Verona, Italy. Each liver biopsy was cut at a different thickness (3, 5, and 8 μm) and stained with both Oil Red O and conventional hematoxylin and eosin for intraoperative consultation. The degree (percentage of hepatocytes involved) of fatty changes was recorded. The results obtained during the intraoperative consultation were finally compared with the formalin-fixed and paraffin-embedded permanent section. ResultsAssessment of steatosis on hematoxylin and eosin frozen sections was reported as mild in 17 cases (85%), moderate in 2 cases (10%) and severe in 1 case (5%). Oil Red O frozen sections reported the following results: mild steatosis in 16 cases (80%), moderate in 2 cases (10%), and severe in 2 cases (10%). The percentage of liver steatosis obtained with Oil Red O was consistent in all cases with that of the permanent sections. The staining procedure for Oil Red O required approximately 18 minutes. ConclusionsOil Red O special stain is a fast and inexpensive tool to improve the assessment of steatosis on frozen biopsies during liver transplantation.