Unexpected Pathological Findings Research Articles

Beyond acute appendicitis: a single-institution experience of unexpected pathology findings after 989 consecutive emergency appendectomy.

Appendiceal neoplasms (ANs) are rare, with an estimated incidence of around 1%: neuroendocrine tumours (NETs) and low-grade appendiceal mucinous neoplasms (LAMNs) comprise most cases. Most tumours are cured by appendectomy alone, although some require right hemicolectomy and intra-operative chemotherapy. The aim of the present study is to evaluate our institution's experience in terms of the prevalence of AN, their histological types, treatment and outcomes in adult patients undergoing emergency appendectomy. Single-centre retrospective cohort analysis of patients treated for acute appendicitis at a large academic medical centre. Patients with a diagnosis of acute appendicitis (AA) where further compared with patients with acute appendicitis and a histologically confirmed diagnosis of appendiceal neoplasm (AN). A diagnosis of acute appendicitis was made in 1200 patients. Of these, 989 patients underwent emergency appendectomy. The overall incidence of appendiceal neoplasm was 9.3% (92 patients). AN rate increased with increasing age. Patients under the age of 30 had a 3.8% (14/367 patients) rate of occult neoplasm, whereas patients between 40 and 89years and older had a 13.0% rate of neoplasm. No difference was found in clinical presentations and type of approach while we found a lower complicated appendicitis rate in the AN group. ANs are less rare with respect to the literature; however, clinically, there are no specific signs of suspicious and simple appendicectomy appears to be curative in most cases. However, age plays an important role; older patients are at higher risk for AN. ANs still challenge the non-operative management concept introduced into the surgical literature.

Routine Histopathologic Analysis of Hip and Knee Bone Specimens After Total Joint Arthroplasty.

Total hip and total knee arthroplasties (THA/TKA) are some of the most common elective surgeries done in the United States. Routine histopathologic analysis of hip and knee bone specimens after total joint arthroplasty commonly occurs to identify unexpected pathologic findings and serves as a quality assurance measure. As the most common indication for THA and TKA is osteoarthritis, the practice of routine histopathologic analysis may not be routinely warranted. There is no clear consensus on the cost-effectiveness of this practice, and the literature has questioned both the clinical relevance of discrepancies between surgeon diagnosis and histopathological diagnosis and raised concerns about variance in the histological evaluation of resected specimens by pathologists. Femoral head analysis in the setting of femoral neck fractures has been previously reported, yet there is no clear overview for this topic in the setting of elective THA. The histopathologic features of bone specimens during routine total joint arthroplasty, the cost-effectiveness, and current recommendations will be reviewed.

115 Total laparoscopic hysterectomy for management of large cesarean scar defect causing secondary amenorrhea: A case report

We present the clinical course of a multiparous woman diagnosed with a large cesarean scar defect (CSD)who underwent hysterectomy. We also review the diagnosis of isthmocele, our surgical management, and the unexpected pathology findings of epithelioid trophoblastic tumor (ETT). A 42-year-old female with history of four prior cesarean sections presented 18 months postpartum with secondary amenorrhea. She was diagnosed with a large lower uterine segment isthmocele on transvaginal ultrasonography. The patient had completed childbearing and opted for surgical management via hysterectomy. She underwent total laparoscopic hysterectomy. Surgery was notable for significant adhesions from the lower uterine segment to the bladder, requiring dissection via an inferior and lateral approach after ligation of the uterine vessels. Pathologic examination revealed an epithelioid trophoblastic neoplasm. The tumor was described as 2.5 cm x 1 cm, confined to the uterus, and diffusely infiltrating the lower uterine segment without invasion into the surrounding tissue. Negative margins were identified. The patient underwent consultation with Gynecology Oncology who recommended surveillance with serial beta-human chorionic gonadotropin and imaging. The clinical presentation and diagnosis of CSD have been thoroughly described. Patients commonly present with postmenstrual spotting, and diagnosis can be made via transvaginal ultrasound. In women who have completed childbearing, hysterectomy is a reasonable treatment option. Many approaches to repair of CSD have been proposed, however approach to hysterectomy in patients with large isthmoceles has not been well documented. Moreover, while desmoid tumors have been described as an extremely rare finding within a CSD, we could only find a single case report in which an ETT was found in someone with a CSD. We reviewed the literature surrounding CSDs in the context of our patient’s clinical course. We concluded that: 1) high suspicion of CSD is warranted in a patient with unexplained amenorrhea and prior cesareans; 2) during hysterectomy, performing adhesiolysis by starting at the vesicocervical tissue and progressing superiorly may be helpful in the case of significant adhesive disease; and 3) is possible that ETT is related to CSD but further research is needed to examine this relationship.View Large Image Figure ViewerDownload Hi-res image Download (PPT)View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Intraoperative decision making in bariatric surgery

Background: Surgeons may encounter unexpected anatomical or pathological findings during various bariatric surgical procedures for which they must make prompt and critical decisions that had not been planned prior to the operation. In this practice review, we present our experiences with unexpected challenges and on-table decision making in bariatric surgery to share our knowledge with colleagues who may encounter the same challenges during bariatric surgery. This paper's content is of applied learning and practical value focusing on challenging intraoperative decision making; however, it does not discuss the details of the various techniques used during surgery.Methods: This work is a single-center retrospective review of operations carried out on patients who had unexpected intraoperative findings during bariatric surgery despite the implementation of detailed preoperative evaluations that would have otherwise suggested standard procedures. These findings resulted in abandoned surgery or laparoscopic sleeve gastrectomy instead of the intended Roux-en-Y gastric bypass.Results: A total of 449 patients had received various bariatric interventions in our unit between 2012 and 2016. Eleven patients, representing approximately 2.4% of the total number of patients surveyed had met the inclusion criteria and were added to the final list for analysis. The mean age of the included patients was 40.82 years (range: 30–51 years), and seven of the patients, representing approximately 63.6% of the included cases, were female. The mean body mass index of the 11 cases was 40.8 (range: 38–48). Only two cases (18.9%) had had their surgery abandoned; the rest (81.1%) had received laparoscopic sleeve gastrectomy instead of Roux-en-Y gastric bypass. None of the 11 patients had perioperative morbidity or mortality.Conclusion: Intraoperative decision making for unexpected findings in bariatric surgery is challenging. In these circumstances, surgeons must make prompt and critical decisions, including abandoning the operation. The available literature on this subject is unsurprisingly limited because of the rarity of such findings.

Biliary hyperkinesia: an indication for cholecystectomy?

The main indications for laparoscopic cholecystectomy are stone-related diseases in adults. With a normal abdominal ultrasound (US), a hepatobiliary iminodiacetic acid (HIDA) scan with ejection fraction (EF) is recommended to evaluate gallbladder function. Biliary dyskinesia or low gallbladder EF (EF < 35%) is a recognized indication for cholecystectomy. Recent articles report long-term resolution of symptoms in children with high EFs on the HIDA scan. The purpose of this study is to evaluate the response of patients with biliary colic and hyperkinetic gallbladder to cholecystectomy. We suggest that laparoscopic cholecystectomy might be a considerable surgical option in a subset of the adult population whose workup for food-related biliary abdominal pain is negative except for the high-value EF on HIDA scan. Data were consecutively collected from all patients who underwent laparoscopic cholecystectomy between June 2012 and June 2019 at a single institution. Cases were identified using Current Procedural Terminology codes. Patients older than 17years of age with the negative US (no stone, no sludge, no gallbladder wall thickening) and EF greater than 80% on cholecystokinin (CCK)-HIDA scan were included in this study. All patients were seen at 2weeks and 10-16months after surgeries. Over 7years from June 2012 until June 2019, of 2116 patients who underwent laparoscopic cholecystectomy, 59 patients (2.78%) met study criteria. Postprandial abdominal pain was the most common symptom (43, 72.90%) followed by nausea/vomiting. Forty-seven patients (74.6%) had a reproduction of symptoms with CCK infusion. The average EF was 88.51%. Final pathology showed chronic cholecystitis in 41 (69.5%) patients, cholesterolosis in 13 (22%), polyp in 2 (3.4%). Thirty-six (61%) patients had complete resolution of symptoms, 9 (15%) patients had partial resolution, and 14 (24%) patients had no change. There was a complete resolution rate of 61% and an improvement rate of 76%. In patients with biliary symptoms, negative ultrasound, and elevated EF on HIDA scan (EF > 80%), laparoscopic cholecystectomy led to a significant rate of symptomatic relief. Interestingly, 94% also had unexpected pathologic findings. This disease process requires further analysis, but this could represent a new indication for laparoscopic cholecystectomy in the adult population.

Unexpected risk of gynecological malignant and premalignant disease in women undergoing hysterectomy for pelvic organ prolapse

Aim: To investigate the incidence of unexpected malignant and premalignant gynecological pathological findings among women who underwent hysterectomy due to pelvic organ prolapse (POP). Methods: In this retrospective study, the medical reports of women who underwent hysterectomy for POP between 2007 and 2019 were investigated to reveal unexpected malignant and premalignant lesions. The possible relationship between pathological results and other variables was evaluated statistically. Results: The hysterectomy was performed by abdominal (160, 30.53%), laparoscopic (62%, 11.83%) and vaginal approaches (302, 57.63%) in 524 patients with POP indication. Thirty five patients (6.67%) had unexpected premalignant or malignant pathological findings found on hysterectomy specimens. Simple hyperplasia was found in 18 patients (3.44%), complex hyperplasia in two patients (0.38%); CIN-1 (LSIL) low grade cervical intraepithelial dysplasia in nine patients (1.7%), CIN-II, moderate dysplasia in two patients (0.38%); CIN-III, severe dysplasia in one patient (0.19%); vaginal carcinoma in two patients (0.38%) and endometrial carcinoma in one patient (0.19%). In the vaginal hysterectomy group, the incidence of unsuspected gynecological malignancy was founded at the rate of 0.57% (3/524) and the percentage of the group was significantly higher than laparotomic and laparoscopic hysterectomy groups. Statistically significant difference was not found between the groups with respect to unexpected uterine malignancy. Conclusion: Women without abnormal vaginal bleeding do not have high risk of premalignant or malignant pathological reporting after uterovaginal prolapse surgery, however it should not be neglected.

EP.118Triple trouble or normal aging?

Some pathological features such as rods, polyglucosan bodies or COX-negative fibers that can be found in muscle and nerve biopsies are generally linked to specific disorders. The significance of such findings in elderly people is unknown. Here we present unexpected pathological findings in muscle and nerve biopsies of an 81-year-old man who suffered from lower-limb pain, paresthesia and deltoid atrophy, for which a polyneuropathy was suspected. The muscle biopsy showed fiber size variation and groups and atrophic fibers of both type 1 and type 2. The trichrome stain showed numerous fibers with subsarcolemmal accumulations of nemaline bodies (rods). Oxidative enzyme stains showed abundant cytochrome c oxidase (COX)-negative succinate dehydrogenase (SDH)-positive fibers and some targetoid fibers. Nerve biopsy showed reduction of myelinated and unmyelinated axons and 13 polyglucosan bodies. Rods, polyglucosan bodies and paracristalline inclusions were (also) identified by electronic microscopy. Nerve biopsy findings were consistent with an axonal polyneuropathy. However, muscle and nerve biopsy also show features of unexpected disorders without any clinical correlate. Rods can typically be identified in a subset of congenital myopathies, or in sporadic late onset nemaline myopathy (SLONM) and in HIV-associated nemaline myopathy. This patient did not have any clinical features or laboratory findings of nemaline myopathy or SLONM. Polyglucosan bodies are characteristics of polyglucosan body myopathy, a glycogenosis (GSD IV) due to decreased branching enzyme activity. The adult form of the disorder usually presents with progressive spastic paraparesis, neurogenic bladder, dementia and peripheral neuropathy. Apart from the polyneuropathy, our patient did not have any other characteristic features. The biopsy also showed features of mitochondrial dysfunction, which is a phenomenon known to increase with age, although its prevalence is unknown. We present a patient with mild polyneuropathy symptoms and prominent findings in nerve and muscle biopsies, which are held to be highly specific for certain diseases. Whether the pathological findings are responsible for the polyneuropathy and further symptoms are yet to come or whether they are 'just' the result of 'aging' is difficult to establish.

Anatomic pathology data generation in preclinical toxicology evaluation: Troubleshooting and risk management for toxicologists

In routine regulatory toxicology studies, the anatomic pathology endpoints are frequently the most significant element of the study data. They may profoundly influence subsequent clinical development and use of a test article, with implications for both human safety and for the fate of key commercial assets. Unfortunately (in common with other perceptual medical specialties), anatomic pathology data are also among the most subjective endpoints in regulatory toxicology studies - a challenge magnified by the fact that not only the diagnostic data but the anatomic pathologist's interpretation of it in their narrative report represent raw data within a regulated study (United States Federal Register, 1987). A strategy for minimizing and managing the risk of misdiagnosis/misinterpretation of pathology data is critical for any preclinical toxicology development program and is a collaborative approach between study directors, study monitors and toxicologists and toxicologic pathologists. The article provides a basic understanding of the sources of error and limitations of anatomic pathology evaluation, a starting point for troubleshooting and a basis for a sound management strategy. It describes common reasons for unexpected or inconsistent pathology findings and sets out to provide a framework for toxicologists to approach commissioning and critically evaluating their pathology data, and for identifying situations where additional third-party advice and review may be justified.

Resolution of unexpected pregnancy-related findings in a rat embryofetal development and toxicokinetic study of monoclonal antibodies specific for hCMV.

Developmental and reproductive toxicity testing is not uniformly warranted for biopharmaceuticals that lack relevant targets in test species. However, RG7667, consisting of two monoclonal antibodies specific for human cytomegalovirus (hCMV), was intended for administration to pregnant women to prevent transmission of CMV to the developing fetus. Considering the target indication, a Pilot Embryo Fetal Development/Toxicokinetic study was conducted to assess toxicokinetics in the dam and fetuses and general tolerability. RG7667 administered intravenously to presumed pregnant Sprague-Dawley rats was well tolerated with no clinical signs in any dam and comparable litter sizes and viability across groups. However, at cesarean section, hepatic necrosis and pancreatic edema were identified in two dams administered RG7667, with no clear dose relationship. Investigation of total protein, albumin, and transaminase activity in residual serum from TK samples demonstrated striking hypoproteinemia and elevated transaminases limited to these two dams. Overall, these pathology findings in dams were considered of uncertain relationship to RG7667; therefore, a subsequent Pivotal EFD study was conducted, which did not repeat the liver or pancreatic findings. The results of the Pivotal study confirmed the lack of overt toxicity, teratogenicity, or effects on litter size and viability when human or humanized monoclonal antibodies that lack an endogenous target are administered IV to rats during pregnancy. With these additional data, we concluded that the unexpected pathology findings in the Pilot study were not specific to RG7667, but rather highlight some clinical pathology and macroscopic/microscopic findings that can occur during pregnancy in rats.

Pathology Findings in Medical School Anatomy Cadavers

This article was migrated. The article was not marked as recommended. With more medical schools in the United States and abroad turning to virtual anatomy instead of gross dissection of actual cadavers, unexpected pathological findings may not be encountered as teaching opportunities. By using real cadavers the cause of death information provided might confirm pathology which is found in the course of routine anatomical dissection. Additional pathology not attributable to cause of death adds further to the experience of the cadaver dissection. Over the course of four academic years, human cadavers at New York Institute of Technology College of Osteopathic Medicine were sampled based on encountered gross pathological findings. Over the four years, there were 64 cadavers sampled randomly and forty two percent of the cadavers had findings related to cause of death. Sixty-six percent of the cadavers had findings which were not related to the cause of death. Thus, not only is pathology abundant in human anatomy cadavers and a source of important medical education but additional pathology outside of cause of death is an even greater source of teaching material. The benefits of human anatomy dissection are good medical educational sources with or without clinical information in the form of cause of death. Having limited clinical information may further enhance the educational value of anatomy dissection.

Unexpected pathological findings after laparoscopic cholecystectomy - analysis of 1131 cases.

IntroductionGallbladder specimens are routinely sent for histopathological examination after cholecystectomy in order to rule out the presence of unexpected pathological findings.AimTo establish the overall incidence of unexpected pathological findings in patients who underwent laparoscopic cholecystectomy for symptomatic gallbladder disease and determine whether the macroscopic appearance of the gallbladder in ultrasound examination could be a valid method for identifying patients with gallbladder malignancy.Material and methodsA retrospective study was conducted between 2013 and 2015. All histological reports (n = 1131) after cholecystectomy were searched for unexpected pathological findings. In cases where unexpected pathological findings were identified the additional analysis of preoperative abdominal ultrasound examination (USG) was done to determine the usefulness of USG in diagnosis of gallbladder malignancy.ResultsOf the 1131 patients included in the study, 356 (31.47%) were male and 774 (68.43%) were female. Unexpected pathological findings were present in 21 cases. The overall incidence of unexpected pathological findings was 1.86%. Only in 5 patients were suspicious appearances of gallbladder observed in preoperative ultrasound examination. In 16 patients there was no suspicion of malignancy. The positive predictive value of USG was 0.238.ConclusionsThe incidence of unexpected pathological findings after laparoscopic cholecystectomy was 1.86%. Ultrasonography has low positive predictive value for identifying patients with malignant findings in a gallbladder specimen.

Unexpected Appendiceal Pathologies and Their Changes With the Expanding Use of Preoperative Imaging Studies.

PurposeThe preoperative diagnosis of acute appendicitis is often challenging. Sometimes, pathologic results of the appendix embarrass or confuse surgeons. Therefore, more and more imaging studies are being performed to increase the accuracy of appendicitis diagnoses preoperatively. However, data on the effect of this increase in preoperative imaging studies on diagnostic accuracy are limited. We performed this study to explore unexpected appendiceal pathologies and to delineate the role of preoperative imaging studies in the diagnosis of acute appendicitis.MethodsThe medical records of 4,673 patients who underwent an appendectomy for assumed appendicitis between 1997 and 2012 were reviewed retrospectively. Pathological results and preoperative imaging studies were surveyed, and the frequencies of pathological results and preoperative imaging studies were investigated.ResultsThe overall rate of pathology compatible with acute appendicitis was 84.4%. Unexpected pathological findings, such as normal histology, specific inflammations other than acute appendicitis, neoplastic lesions, and other pathologies, comprised 9.6%, 3.3%, 1.2%, and 1.5%, respectively. The rate of unexpected pathological results was significantly reduced because of the increase in preoperative imaging studies. The decrease in normal appendices contributed the most to the reduction while other unexpected pathologies did not change significantly despite the increased use of imaging studies. This decrease in normal appendices was significant in both male and female patients under the age of 60 years, but the differences in females were more prominent.ConclusionUnexpected appendiceal pathologies comprised 15.6% of the cases. Preoperative imaging studies reduced them by decreasing the negative appendectomy rate of patients with normal appendices.

Pateʼ or Perforation: A Transcolonic Liver Biopsy?

A 68 year old woman underwent screening colonoscopy. The cecum was reached, but residual stool was present throughout the colon. A total of 7 sessile polyps ranging from 5-8 mm were removed successfully using hot snare polypectomy between the ascending colon and splenic flexure. One additional multilobulated polyp 2 cm in diameter was removed from the proximal transverse colon with a hot snare. Post-procedure recovery was routine, and the patient was asymptomatic at discharge. Three days later, the attending pathologist called after initial specimen review. She announced hepatic tissue was present on the third specimen, a proximal ascending colon polyp, and suggested the patient had transcolonic sampling of her hepatic parenchyma. The patient was called and reported mild upper abdominal discomfort. She denied any fever, chills or abdominal distention, and was tolerating a normal diet while passing flatus and stool. On further questioning, she noted her pre-procedure diet included liver ingested a few days before the colonoscopy. Given concern for an unrecognized perforation, she was advised to go to the emergency department, where a CT scan showed no evidence of perforation or bleeding and she was discharged home. Complete review of all pathology specimens demonstrated no evidence of hepatic parenchyma on any other slides. A literature search revealed no cases where hepatic injury occurred during colonoscopy as a result of transmural passage of polypectomy tools. Images from the colonoscopy report were reviewed and demonstrated no evidence of a tissue defect at any polypectomy site. This information, combined with the lack of thermal injury seen on the liver specimen, led to decreased concern for transcolonic hepatic biopsy. Another possibility, contamination with a liver biopsy prepared in the same laboratory, was deemed less likely given review of records showing no liver biopsies on the processing date. To assess the final possibility, ingested animal liver retained in the colon due to incomplete preparation, the attending pathologist obtained the patient's recipe and prepared the same dish. Raw and cooked samples of this liver were sectioned for review. Neither sample had an appearance similar to the findings on the colonic specimen. While the true origin of the colonic liver specimen is unknown, this case highlights the importance of a thorough investigation when unexpected pathology findings occur during routine endoscopy.Figure 1Figure 2

Analysis of unexpected non-colorectal lesional histopathology in 1252 resections for suspected CRLM

Aims: Resection is a safe and effective treatment for colorectal liver metastases (CRLM). Surgery is indicated by imaging findings with a history of synchronous or metachronous colorectal cancer. This study examined cases where patients were found to have non-colorectal lesions after resection for CRLM. Methods: Liver resections were identified from a prospective database. Additional data were retrieved from electronic records. Resections were divided into those where histology demonstrated CLRM or complete pathological response to chemotherapy (A) and those where an alternative pathology was detected (B). Univariate analyses with Mann-Whitney, Fisher's exact and Kendall's tau tests were performed. Results: There were 1252 resections (2002–2012). Group A 1213 (96.9%), Group B 39 (3.1%). The groups did not differ in age, sex or synchronous/metachronous disease. Group B patients had significantly fewer tumours (p=0.006), with significantly smaller maximum sizes (p<0.001). Group B patients also had significantly lower T (p=0.031), N (p<0.001) and Dukes’ (p<0.001) stages. In addition to this, the CEA level was also significantly lower in group B patients (median A=8.1, B=1.8, p<0.001). Group B histopathology is shown in the table. 25/31 in group B had preoperative MRI (data unavailable in 8). 32 resections were undertaken where the primary is known to have been T0N0 (Dukes' A). Of these 5 (16%) were in group B; two of these had malignant pathology (HCC and cholangiocarcinoma). Conclusions: Unexpected non-colorectal lesional pathology findings after resection for CRLM are rare, having a frequency of occurrence similar to mortality. In a small proportion of the cases there was some equivocation in the reports of preoperative imaging. However, all proceed on the basis they were CRLM. Haemangiomata, which were often hyalinised, were the most common finding. 9/39 had alternative malignant pathology. Current practice is to avoid lesional biopsy before liver resection because of the risk of tumour seeding. The present data support this.

MP16-03 THE IMPACT OF A LEARNING CURVE IN THE PERFORMANCE OF MRI-US FUSION-TARGETED PROSTATE BIOPSY: IMPROVEMENTS IN CANCER DETECTION OVER TIME

INTRODUCTION AND OBJECTIVES: Mounting evidence suggests that MRI-ultrasound fusion-targeted prostate biopsy (MRFTB) may provide clinical benefit for men with suspicion of prostate cancer. We investigated outcomes of MRF-TB over time to evaluate how the performance characteristics vary with increasing operator experience. METHODS: Between June 2012 and April 2015, 566 men underwent MRF-TB by a single surgeon. A total of 429 men with no prior prostate cancer therapy had pre-biopsy multiparametric MRI (mpMRI) performed at our institution and reviewed by a single radiologist. During this time period, quality assurance efforts included team review of MRI interpretation, biopsy maps and outcome, and discussion of discrepant cases or unexpected pathology findings. We evaluated the cancer detection rates (CDR) among men with high mpMRI suspicion scores (mSS) as a function of operator experience. Trend was assessed using the Cochrane-Armitage test, and characteristics between groups were compared by chi-square or one-way ANOVA. RESULTS: All subjects were grouped according to the order of biopsy (1-60, 61-120, 121-180, 181-240, 241-300, 301-360, 361-429). Among groups, there was no difference in serum PSA (p 1⁄4 0.131) or mSS distribution (p 1⁄4 0.957). Cancer detection among men with mSS 4 or 5 demonstrated a significant, increasing trend as a function of biopsy experience, with CDRs of 63.0%, 69.6%, 77.8%, 68.2%, 88.0%, 84.0%, and 85.7% for groups 1-7, respectively (p 1⁄4 0.014). The CDR among men with mSS 2 or 3 did not demonstrate a trend (p 1⁄4 0.386) (Figure 1). CONCLUSIONS: Among men undergoing pre-biopsy mpMRI followed by MRF-TB, the rate of cancer detection appears to increase as a function of biopsy experience for men with high mpMRI suspicion (mSS 4-5), while little to no change is noted in men at lower suspicion (mSS 2-3). Improved outcomes over time may, in part, reflect evolution of MRI technique and interpretation, but these results additionally suggest that operator experience in the conduct of MRF-TB may play a significant role in optimizing cancer detection. Source of Funding: The Joseph and Diane Steinberg Charitable Trust

OC-060 Analysis of unexpected non-colorectal lesional histopathology in 1252 resections for suspected crlm: Abstract OC-060 Table 1

<h3>Introduction</h3> Resection is a safe and effective treatment for colorectal liver metastases (CRLM). Surgery is indicated by imaging findings with a history of synchronous or metachronous colorectal cancer. This study examined cases where patients were found to have non-colorectal lesions after resection for CRLM. <h3>Method</h3> Liver resections were identified from a prospective database. Additional data were retrieved from electronic records. Resections were divided into those where histology demonstrated CLRM or complete pathological response to chemotherapy (A) and those where an alternative pathology was detected (B). Univariate analyses with Mann-Whitney, Fisher’s exact and Kendall’s tau tests were performed. <h3>Results</h3> There were 1252 resections (2002–2012). Group A 1213 (96.9%), Group B 39 (3.1%). The groups did not differ in age, sex or synchronous/metachronous disease. Group B patients had significantly fewer tumours (p = 0.006), with significantly smaller maximum sizes (p &lt; 0.001). Group B patients also had significantly lower T (p = 0.031), N (p &lt; 0.001) and Dukes’ (p &lt; 0.001) stages. In addition to this, the CEA level was also significantly lower in group B patients (median A = 8.1, B = 1.8, p &lt; 0.001). Group B histopathology is shown in the Table 1. 25/31 in group B had preoperative MRI (data unavailable in 8). 32 resections were undertaken where the primary is known to have been T0N0 (Dukes’ A). Of these 5 (16%) were in group B; two of these had malignant pathology (HCC and cholangiocarcinoma). <h3>Conclusion</h3> Unexpected non-colorectal lesional pathology findings after resection for CRLM are rare, of the same order of frequency as mortality. In a small proportion of the cases there was some equivocation in the reports of preoperative imaging. However, all proceed on the basis they were CRLM. Haemangiomata, which were often hyalinised, were the most common finding. 9/39 had alternative malignant pathology. Current practice is to avoid lesional biopsy before liver resection because of the risk of tumour seeding. The present data support this. <h3>Disclosure of interest</h3> None Declared.

Histopathology from the dissecting room: are cadavers a suitable source of educationally useful histopathology specimens?

Objectives:The requirement of the General Medical Council to ‘reduce factual overload’ has led to the development ofintegrated curricula in which the knowledge base related to basic medical sciences has been greatly restricted. The time allocated to pathology teaching in medical schools has been decreased. The challenge for educators is to introduce effectivemethods of learning pathology into an integrated, student-centred curriculum. The aim of this study is to assess the tissuederived from cadaveric material and report its potential for use in teaching histopathology. Methods: We have previously reported how we use cadavers’ medical histories when introducing students to their ‘first patient’.The medical histories of the seventeen cadavers that were dissected during one academic session were reviewed for evidence ofreported pathology. During dissection unexpected pathological findings were noted. Standard histological processing was carried out on pathological tissue from the cadavers, a prosection and a specimen which was displayed in a museum pot. Thesespecimens were then assessed for educational value by an expert clinical histopathologist. Results: We find that the availability of a real medical history combined with gross and microscopic pathology encourages integration of basic medical sciences and promotes the learning of both gross and microscopic pathology in the dissecting room. Conclusion:The dissecting room provides ample material to introduce pathological concepts to undergraduate medical students and this material is a valuable resource for teaching histopathology

Cancer tracking: Clinician compliance and program outcome.

Certain laboratory tests are critical for patient care and must be communicated rapidly. Professional societies have developed guidelines for reporting of "critical values" and significant or unexpected surgical pathology findings. Urgent diagnoses requiring rapid reporting include new or unexpected diagnoses of malignancy. The University of Missouri established a "cancer-tracking" protocol in which all diagnoses of malignancy require acknowledgment by the responsible clinician. We reviewed 5 months of compliance with the cancer-tracking protocol. The protocol requires the Department of Pathology to send a letter to the responsible clinician requesting acknowledgment of the report. In total, 1,155 confirmation requests were sent to the physicians named on the request form. Following the first letter, 692 acknowledgments were received, and 356 acknowledgments followed the second letter. In 107 (9%) cases, no response was received. Confirmation that the physician caring for a patient receives a pathology diagnosis is important for patient management and quality assurance. While the surgical pathology report was placed in the chart, it was impossible to confirm that the responsible physician had reviewed the report in 9% of cases. Techniques for communication and confirmation of transmission of anatomic pathology diagnoses need to be developed.

Lymphoepithelial cysts of the pancreas a management dilemma

Pancreatic lymphoepithelial cysts (LECs) are rare, benign lesions that are typically unexpected post-operative pathological findings. We aimed to review clinical, radiological and pathological features of LECs that may allow their pre-operative diagnosis. Histopathology databases of two large pancreatic units were searched to identify LECs and notes reviewed to determine patient demographic details, mode of presentation, investigations, treatment and outcome. Five male and one female patients were identified. Their median age was 60 years. Lesions were identified on computed tomography performed for abdominal pain in two patients, and were incidentally observed in four patients. Five LECs were located in the tail and one in the body of the pancreas, with a median cyst size of 5 cm. Obtaining cyst fluid was difficult and a largely acellular aspirate was yielded. The pre-operative diagnosis was mucinous cystic neoplasm in all patients. This series of patients were treated distal pancreatectomy and splenectomy. A retrospective review of radiological examinations suggested that LECs have a relatively low signal on T2 imaging and a high signal intensity on T1 weighted images. LECs appear more common in elderly males, and are typically incidental, large, unilocular cysts. Close attention to signal intensity on MRI may allow pre-operative diagnosis of these lesions.

Incidence and outcomes of unexpected pathology findings after appendectomy

PurposePathologic evaluation of the appendix after appendectomy is routine and can identify unexpected findings. We evaluated our experience in children undergoing appendectomy to review the clinical course of patients with unexpected appendiceal pathology. MethodsAfter IRB approval, a retrospective review was conducted on patients who underwent appendectomy from January 1, 1995 to March 1, 2011. Patient demographics, diagnosis, pathological findings, disease outcomes, and treatment were collected only on patients with abnormal pathology. Results3602 patients underwent appendectomy. 113 patients had normal appendices, and 86 patients had unexpected findings, including carcinoid tumor (n=9), pinworm (n=34), granuloma (n=14), eosinophilic infiltrates (n=18), and other (n=11). All cases of carcinoid tumor were completely resected, with no recurrence or need for reoperation. Of the 34 patients with pinworm infestation, 41.2% underwent antimicrobial therapy, and none had post-operative symptoms. One patient (7%) with an appendiceal granuloma developed Crohn’s disease. Three patients (16.7%) with eosinophilia developed symptomatic intestinal eosinophilia. ConclusionsPediatric appendiceal carcinoid is an incidental finding; in this series, none required further intervention. Appendiceal granulomas are not commonly associated with developing Crohn’s disease in the short term. Routine antibiotics for the treatment of pinworms are adequate. Patients with appendiceal eosinophilia may develop symptomatic intestinal eosinophilia.