ABSTRACT Twin reversed arterial perfusion (TRAP) sequence is a rare complication of monochorionic twinning whereby a donor twin perfuses an acardiac twin via aberrant vascular anastomoses. The resulting paradoxical retrograde blood flow supplying the acardiac twin is oxygen-poor, leading to some of the most severe malformations encountered in humans. Though the first descriptions of acardiac twins date back to at least the 16th century, the pathophysiologic processes which underpin the development of TRAP sequence are still being elucidated. Theories on the pathogenesis of TRAP sequence include deficiencies intrinsic to the embryo and primary abnormalities of the placental vasculature. Autopsy studies continue to provide clues to the underlying pathogenesis of TRAP sequence, and the characterization of the spectrum of manifestations that can be observed in acardiac twins. Herein, we present the clinical, autopsy, and molecular findings in a unique case of TRAP sequence. Novel findings include a primitive cloaca-like structure and chromosomal aberrations involving 6q11.1 and 15q25.1. (TRAP anastomoses oxygenpoor, oxygenpoor oxygen poor, poor oxygen-poor humans th century elucidated vasculature Herein clinical autopsy cloacalike cloaca like 6q111 q 6q11 1 6q11. 15q251 15q25 15q25.1 6q1 15q2 15q25. 6q 15q

ABSTRACT Papillary renal cell carcinoma (PRCC) is the second most common renal cell carcinoma (RCC), accounting for 10-15% of cases. Mucinous tubular and spindle cell carcinoma (MTSCC), on the other hand, accounts for only 1% of renal tumors and has a more favorable prognosis compared to PRCC. We report a 75-year-old female with a left upper pole solid renal mass displaying features of both papillary renal cell carcinoma (PRCC) and mucinous tubular and spindle cell carcinoma (MTSC). In this case, a shaggy luminal surface, multiple papillations, and psammoma bodies, absence of E-cadherin expression, and strong CD10 expression favored PRCC. Both immunohistochemistry and genomic analysis are critical to diagnose and differentiate tumors that may have overlapping features accurately. PRCC (PRCC RCC, RCC , (RCC) 1015% 1015 10 15% 15 10-15 cases MTSCC, MTSCC (MTSCC) hand 1 75yearold yearold 75 year old MTSC. MTSC . (MTSC) case surface papillations bodies Ecadherin E cadherin CD CD1 accurately (RCC 101 10-1 (MTSCC 7 (MTSC 10-

ABSTRACT Neuroendocrine breast cancer (NEBC) is a rare and heterogeneous entity. It most commonly presents a luminal phenotype and a worse prognosis. When diagnosed in an advanced stage, metastasis from another neuroendocrine tumor should be excluded. This case features a premenopausal woman with an oligometastatic breast large cell neuroendocrine carcinoma, estrogen receptor (ER) positive, and human epidermal growth factor receptor 2 (HER2) negative. Since the patient was very symptomatic at the presentation of the disease, chemotherapy was started. Complete radiological response of the metastatic disease was achieved, and the patient was then submitted to radical breast surgery and bilateral oophorectomy. She subsequently underwent radiation therapy. Since then and to date, she has been under endocrine therapy (ET) and a CDK4/6 inhibitor (CDK4/6i), with no evidence of malignant disease. Evidence to guide the choice of treatment for these tumors is currently scarce. In cases with oligometastatic disease, radical treatment should be considered. Given that this entity is rare, its reporting should be encouraged. NEBC (NEBC prognosis stage excluded carcinoma ER (ER positive HER2 HER (HER2 negative started achieved oophorectomy date ET (ET CDK46 CDK CDK4 6 CDK4/ CDK4/6i, CDK46i CDKi CDK4/6i , 6i i (CDK4/6i) scarce considered encouraged (HER (CDK4/6i

ABSTRACT Trisomy 13, known as Patau syndrome, is a common aneuploidy with a well-known clinical phenotype. This case report describes a trisomy 13 patient with unusual autopsy findings, including features resembling the Beckwith-Wiedemann Spectrum. Due to abnormalities of gestational ultrasounds, a prenatal karyotype of amniotic fluid cells was performed, which resulted in 47, XY+13. Autopsy microscopy studies identified leptomeningeal glioneuronal heterotopia, which was not described as belonging to Patau syndrome. Other atypical findings were diffuse hyperplasia of pancreatic islets of Langerhans and adrenals enlargement with marked adrenocortical cytomegaly, characteristically seen in the Beckwith-Wiedemann Spectrum. Molecular genetic tests were not performed for the Beckwith-Wiedemann Spectrum. Still, due to the rarity of both disorders, this report may support the evidence that trisomy 13 can affect tissue organization and lead to unusual histopathologic features resembling classic overgrowth disorders. syndrome wellknown well phenotype 1 BeckwithWiedemann Beckwith Wiedemann Spectrum ultrasounds 47 XY13 XY XY+13 heterotopia cytomegaly Still disorders 4 XY1 XY+1 XY+

ABSTRACT Primary leiomyosarcoma with osteosarcomatous differentiation of the breast is an uncommon entity. We present the case of a 37-year-old female who presented with a lump in the breast and pulmonary lesions on PET-CT, for which she underwent a toilet mastectomy. Histopathological examination revealed a tumor with cells arranged in sheets. These tumor cells had moderate eosinophilic cytoplasm, highly pleomorphic, irregular hyperchromatic nuclei, coarse chromatin, and prominent nucleoli. Areas with spindle-cell morphology were noted. Osteoid was seen intermingling with the tumor along with numerous osteoclast-like multinucleate giant cells. A wide panel of Immunohistochemistry was applied, and Desmin, h-Caldesmon, SMA, and Vimentin were positive. The patient died 3 months post-surgery and had a recurrence at the surgical site. entity 37yearold yearold 37 year old PETCT, PETCT PET CT, CT PET-CT mastectomy sheets cytoplasm pleomorphic nuclei chromatin nucleoli spindlecell spindle cell noted osteoclastlike osteoclast like applied Desmin hCaldesmon, hCaldesmon h Caldesmon, Caldesmon h-Caldesmon SMA positive postsurgery post surgery site

ABSTRACT Ovarian steroid cell tumors are rare, representing less than 0.1% of all ovarian neoplasms. Among the myriad causes of hirsutism, ovarian tumors account for 1% of the reported cases. We present the case of a 49-year-old parous postmenopausal woman who sought medical attention for hirsutism for 2 years. This case illustrates the unusual and interesting connection between rare ovarian pathology and the clinical manifestation of hirsutism in a postmenopausal patient. Her ultrasonography and MRI showed a right adnexal mass of solid-cystic consistency with thin septations. Her laboratory workup revealed high levels of total testosterone of 256 ng/ml (8.4-48.1ng/ml) and free testosterone of 7.36 pg/ml (0.2-4.1 pg/ml), while DHEAS - 234 µg/dl (35.4-256 µg/dl) and CA125 - 15.8U/L (0.0-35 U/L) were in the normal range. She underwent exploratory laparotomy with a total abdominal hysterectomy and oophorectomy. Histopathological examination and immunohistochemistry conclusively established the presence of a steroid cell tumor, specifically classified as "Not Otherwise Specified"(NOS), in the right ovary. 01 0 1 0.1 neoplasms cases 49yearold yearold 49 year old years patient solidcystic solid cystic septations 25 ngml ng ml 8.448.1ng/ml 84481ngml 8.4 48.1ng/ml 8 4 48 1ng (8.4-48.1ng/ml 736 7 36 7.3 pgml pg 0.24.1 0241 0.2 4.1 (0.2-4. pg/ml, , pg/ml) 23 µgdl µg dl 35.4256 354256 35.4 35 (35.4-25 CA CA12 158UL UL 15 8U L U 0.035 0035 0.0 (0.0-3 U/L range oophorectomy tumor Not SpecifiedNOS, SpecifiedNOS Specified NOS Specified"(NOS) ovary 0. 448 84 8. 481ngml 73 3 7. 24 0.24. 024 02 41 4. (0.2-4 4256 35.425 35425 354 35. (35.4-2 CA1 035 0.03 003 00 (0.0- Specified"(NOS 44 0.24 (0.2- 425 35.42 3542 (35.4- 03 (0.0 (0.2 42 (35.4 (0. (35. (0 (35 ( (3

ABSTRACT Giant hepatic hemangiomas are occasional in patients with cirrhosis. It remains a challenge to decide on the need for treatment and choose the most appropriate intervention. A 62-year-old woman was recently diagnosed with cirrhosis and complained of upper abdominal fullness, reduction in oral food intake, and weight loss of 6 kg over the last three years. Upper digestive endoscopy evidenced thin-caliber esophageal varices and significant extrinsic compression of the lesser gastric curvature. Abdominal computed tomography revealed an exophytic tumor in the left hepatic lobe, measuring 11.5 cm, which had progressive centripetal contrast enhancement from the arterial phase, compatible with hepatic hemangioma. Serum tumor markers were negative, and her liver function was unimpaired. The patient underwent surgical resection (non-anatomical hepatectomy of segments II and III) which had no immediate complications, and the histopathological evaluation confirmed cavernous hepatic hemangioma. Two weeks later, she was admitted to the emergency room with jaundice, signs of hepatic encephalopathy, and moderate ascites, and was further diagnosed with secondary bacterial peritonitis. As no perforations, abscesses, or fistulas were observed on subsequent imaging tests, clinical management was successfully carried out. This case highlights that giant hepatic hemangiomas may be symptomatic and warrant treatment. In the setting of cirrhosis and portal hypertension, physicians should be aware of the risk of hepatic decompensation following surgical resection, even in patients with Child-Pugh class A. intervention 62yearold yearold 62 year old fullness intake years thincaliber thin caliber curvature lobe 115 11 5 11. cm phase hemangioma negative unimpaired nonanatomical non anatomical III complications later jaundice encephalopathy ascites peritonitis perforations abscesses tests out hypertension ChildPugh Child Pugh 1

ABSTRACT Fatty acid oxidation defects are a heterogeneous group of disorders related to the mitochondrial fatty acid oxidation pathway. Carnitine acylcarnitine translocase (CACT) is an enzyme responsible for the unidirectional transport of acylcarnitine across the inner mitochondrial membrane. This enzyme plays a crucial role in the oxidation of fatty acids. The autopsy pathology of the CACT deficiency is described in only a few cases. We describe the autopsy pathology of a child with CACT deficiency dominantly in the form of microvesicular steatosis of the hepatocytes, renal proximal tubular epithelia, cardiac myocytes, and rhabdomyocytes. The diagnosis was further confirmed on whole exome sequencing with compound heterozygous variants in the exon 1 (c.82G>T, p.Gly28Cys; likely pathogenic) and exon 5 (c.535G>A, p.Asp179Asn; uncertain significance) of the SLC25A20 gene. This case elucidates the histopathology of the liver and the detailed autopsy of a case of CACT deficiency from India. pathway (CACT membrane acids cases hepatocytes epithelia myocytes rhabdomyocytes c.82G>T, c82GT cGT c 82G T G (c.82G>T p.Gly28Cys pGly28Cys pGlyCys p Gly28Cys Gly Cys pathogenic c.535G>A, c535GA cGA 535G A (c.535G>A p.Asp179Asn pAsp179Asn pAspAsn Asp179Asn Asp Asn significance SLCA SLC SLC25A2 gene India c.82G>T GT pGly GlyCys c.535G>A GA pAsp AspAsn SLC25A

ABSTRACT Biliary atresia (BA) is a fibro-obliterative cholestatic disease of infancy. The presence of cartilage in the resected tissue is an uncommon finding. We documented the presence of both mature and immature hyaline cartilage in the portal plate and the wall of the gallbladder in a 2-month-old girl infant with BA who had undergone Kasai portoenterostomy. The presence of cartilage could be part of a heterotopia or an uncommon connective tissue metaplasia. The presence of immature cartilage with the merging of the perichondrium with the soft tissue highlights a metaplastic etiology in the index case. (BA fibroobliterative fibro obliterative infancy finding 2monthold monthold 2 month old portoenterostomy metaplasia case

ABSTRACT The effectiveness of the autopsy as an educational tool in forensic medicine courses has been widely acknowledged, and medical students were expected to attend regularly. Nevertheless, the use of autopsies for teaching has dramatically declined in recent years and worldwide despite their high-value benefits. This study aims to understand the importance and relevance of attending autopsies during forensic teaching sessions and identify any challenges that may impede attendance. A self-administered online questionnaire that assesses the knowledge, attitudes, and practices related to autopsies attendance was distributed to fourth-year medical students at the National Defence University of Malaysia and Universiti Sains Islam Malaysia. A total of 99 respondents were involved in this study. Our findings indicate that most respondents (over 85%) demonstrated good knowledge of forensic medicine. Pearson's statistical test revealed a significant correlation between the knowledge and students' attitudes toward autopsy. This study demonstrates the need to strategically integrate autopsy attendance into medical curricula to encourage constructive attitudes and practices among medical students. Students gain the most benefits from frequently attending autopsies. Passionate educators can conduct preparatory sessions to set expectations and address concerns, encourage students to process their experiences, and reinforce learning outcomes in the mortuary setting. Mandatory autopsy teaching should be integrated into the curriculum to ensure medical students have the necessary skills and knowledge to become competent doctors. acknowledged regularly Nevertheless highvalue high value selfadministered self administered fourthyear fourth year 9 over 85% 85 Pearsons Pearson s concerns experiences setting doctors 8

ABSTRACT We report the case of a 77-year-old male who suffered from hypertension and died suddenly. At autopsy, he was found to have hypertensive cardiomegaly and a dissecting syphilitic saccular aneurysm of the ascending aorta and arch with tamponade. Chronic aortic regurgitation, which is often seen in syphilitic aortitis, produces an additive effect to the concentric left ventricular hypertrophy seen in hypertension. 77yearold yearold 77 year old suddenly autopsy tamponade regurgitation aortitis 7