ABSTRACT Atypical parathyroid tumor (APT) is a rare neoplasm of the parathyroid gland, which shows atypical cytological or architectural features and lacks definite diagnosis criteria for malignancy. These cases can cause diagnostic challenges owing to their rarity and similarity with thyroid neoplasm on imaging and fine needle aspiration cytology. Also, differentiating APT from giant parathyroid adenoma or parathyroid carcinoma can be challenging based on clinical, imaging or cytological features. A 49-year-old male presented with clinical features of hyperparathyroidism. On laboratory evaluation, his serum calcium and serum parathyroid hormone was elevated. Imaging studies suggested a possibility of left inferior parathyroid neoplasm, and fine needle aspiration cytology showed features suggestive of parathyroid neoplasm. However, exact categorization of parathyroid tumor was difficult in pre-operative work-up. Possibilities of giant parathyroid adenoma as well as parathyroid carcinoma were considered. A final diagnosis of an atypical parathyroid tumor was made after detailed histopathological evaluation given focal capsular invasion but lack of unequivocal evidence of malignancy in the resected specimen. APT is a rare neoplasm of uncertain malignant potential. Knowledge of the radiological and pathological features will be helpful in accurately identifying the lesion and avoiding misdiagnosis. (APT gland Also 49yearold yearold 49 year old hyperparathyroidism elevated However preoperative pre operative workup. workup work up. up work-up considered specimen potential misdiagnosis 4

ABSTRACT Virchow’s law of thrombosis states that thrombosis in a vessel occurs as a combination of the following: (i) injury to the vessel wall, (ii) stasis of blood flow, and (iii) blood hypercoagulability. Injury to the wall includes infection/inflammation and/or injury to the resident cells of the wall. We postulate that in COVID-19, the SARS-CoV-2 virus directly infects the alveolar type II cell or directly or indirectly infects/injures the pericyte, promoting inflammation and interaction with endothelial cells, thereby causing a cascade of events leading to our observation that thrombosis occurred within the walls of the pulmonary vessels and not in the lumen of the vascular circulation. Virchows Virchow s following i (i ii (ii flow iii (iii hypercoagulability infectioninflammation infection andor COVID19, COVID19 COVID 19, 19 COVID-19 SARSCoV2 SARSCoV SARS CoV 2 SARS-CoV- infectsinjures injures pericyte circulation COVID1 1 COVID-1 SARS-CoV COVID-

ABSTRACT Cryptococcosis occurs primarily in immunocompromised patients. It is difficult to suspect in an immunocompetent patient presenting with a headache. The clinical manifestations of cryptococcosis can be subtle in a patient whose immune system is responding, but inadequate. This is the report of a case of fatal cryptococcosis initially misdiagnosed as a sinus headache on the basis of a telephone call, and then misdiagnosed as aseptic meningitis on the basis of mild findings and negative cerebrospinal fluid cultures. Autopsy revealed unsuspected severe cryptococcal meningoencephalitis. Cerebrospinal fluid nuclear acid amplification (NAA) panels including Cryptococcus should enable the diagnosis of unsuspected cryptococcal meningitis in most cases, but can be false positive, which could be adjudicated by cryptococcal antigen and culture. It will remain important to test for cryptococcal antigen and to maintain a broad differential diagnosis for all patients with meningitis. responding inadequate call cultures meningoencephalitis NAA (NAA cases positive culture

ABSTRACT Castleman disease (CD) is a rare, benign lymphoproliferative disorder, mostly involving the mediastinal lymph nodes, but can occur wherever lymphoid tissue is found. With only a few published case reports, there needs to be more literature on its cytological findings. We report the case of a 63-year-old female presenting with left upper cervical swelling. Fine needle aspiration cytology smears showed variably sized lymphoid follicles with diminished germinal centers, prominence of follicular dendritic cells, and capillaries traversing some of the follicles. The possibility of a hyaline-vascular type of Castleman disease was suggested. Histopathology confirmed the cytological diagnosis. The index case is being presented to discuss the cytological features of the CD along with its histological and immunohistochemical correlation. (CD rare disorder nodes found reports findings 63yearold yearold 63 year old swelling centers cells hyalinevascular hyaline vascular suggested diagnosis correlation 6

ABSTRACT Herein, we report the case of primary amyloidosis with multi-organ involvement in a female patient in her 50s. The patient had a history of relapsing polychondritis, chronic kidney disease, and monoclonal gammopathy of undetermined significance (MGUS). The clinical manifestations included neuropathic pain, sensorimotor polyneuropathy, intrahepatic cholestatic liver injury, gastrointestinal symptoms, dysautonomia, and myocardial thickening. Initial histologic evaluations of the abdominal fat pad aspirate and bone marrow biopsy were negative for amyloid deposition. However, due to a high index of suspicion, a second bone marrow biopsy was performed, confirming the presence of the amyloid protein. Given the patient's complex medical history, other types of amyloidosis, such as AA amyloidosis, AL amyloidosis, and ß2-microglobulin amyloidosis, should also be considered as differential diagnoses. The type of amyloid protein was subsequently identified through laser microdissection of amyloid fibrils followed by liquid chromatography–tandem mass spectrometry as AL-lambda (amyloid light-chain) amyloidosis. The patient presented unfavorable evolution, with progressive dysautonomia, being admitted to the ICU, culminating in refractory circulatory shock, and undergoing an empirical broad-spectrum antibiotic therapy. After a few days, she presented pulseless ventricular tachycardia, culminating in her death, before undergoing specific treatment. This article highlights the crucial role of precise identification in guiding appropriate therapeutic strategies for this complex, yet potentially severe, diseases. Herein multiorgan multi organ 50s s polychondritis disease MGUS. MGUS . (MGUS) pain polyneuropathy injury symptoms dysautonomia thickening deposition However suspicion performed patients ß2microglobulin ßmicroglobulin ß2 microglobulin ß diagnoses chromatographytandem chromatography tandem ALlambda lambda lightchain light chain light-chain evolution ICU shock broadspectrum broad spectrum therapy days tachycardia death treatment severe diseases (MGUS

ABSTRACT Multicystic encephalopathy is a rare neurological finding characterized by the appearance of multiple cystic or cavitary lesions as the result of repetitive episodes of hypoxic-ischemic injury in neonates and infants. We present a rare case of multicystic encephalopathy in a 3-month-old male, born at 34 weeks with Tetralogy of Fallot and multiple comorbidities. Gross examination of the brain during the autopsy revealed multiple irregular cystic lesions and distortion of the brain parenchyma. This case report highlights the uniqueness of multicystic encephalopathy and offers an extensive review of the existing literature, including etiology, clinical presentation, and histopathologic findings. hypoxicischemic hypoxic ischemic infants 3monthold monthold 3 month old male comorbidities parenchyma literature etiology presentation findings

ABSTRACT Dentinogenic ghost cell tumor (DGCT) is a rare benign neoplasm form of calcifying odontogenic cyst (COC) characterized by ghost cells. Although benign, it presents an aggressive behavior. DGCT accounts for 2% to 14% of all COCs and less than 0.5% of all odontogenic tumors. It is a benign odontogenic tumor despite its local invasion and the likelihood of recurrence. To detect recurrence, central DGCT patients must be monitored long-term. We present the case of a 51-year-old male who reported pain in the right upper back tooth region. On examination, a soft to firm, bright red swelling was present in the buccal vestibule and gingival margin of the maxillary right first and second molar, which extended up to the palate. Histopathological analysis confirmed the diagnosis of a DGCT, which occurred in a previously treated calcifying odontogenic cyst. The case is reported here, along with a review of the literature update of such recurred instances in the past. (DGCT COC (COC cells behavior 2 14 05 0 5 0.5 tumors recurrence longterm. longterm long term. term long-term 51yearold yearold 51 year old region examination firm molar palate here past 1 0.

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 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 The present work reports the autopsy findings of a unique case characterized by fatal retroperitoneal hemorrhage following the traumatic rupture of bilateral renal angiomyolipomas. Renal angiomyolipomas are generally benign tumors with an unpredictable clinical course, ranging from asymptomatic to sudden rupture and hemorrhagic shock. They may be associated with genetic disorders such as tuberous sclerosis complex. The case under investigation is unprecedented in the medical literature due to its bilateral nature and fatal outcome. Autopsy analysis revealed an extensive retroperitoneal hemorrhage originating from bilateral ruptured tumors. Microscopic examination found features consistent with bilateral renal angiomyolipoma. Circumstantial information identified a traffic accident before the death, considering it as the cause of the tumors’ traumatic rupture. In this case, due to the severity of the situation, immediate medical measures—such as fluid resuscitation, coagulopathy correction, and surgical treatment, which are usually lifesaving—could not be performed. This led to the patient being declared dead at the scene of the crash. course shock complex outcome angiomyolipoma death situation measuressuch measures resuscitation correction treatment lifesavingcould lifesaving could performed crash

ABSTRACT The lymphocyte-depleted classic Hodgkin lymphoma (LDCHL), the rarest subtype of classic Hodgkin lymphoma (CHL), is usually diagnosed at an advanced stage (stage IV) and one that unusually involves the liver, causing a rapidly progressive clinical course. We describe a 40-year-old immunocompromised man presenting with a progressive non-cholestatic jaundice and intermittent fever. The abdominal ultrasonography revealed a nodular liver with coarse echotexture and periportal hypodensities. The thoracic and abdominal contrast-enhanced computed tomography revealed right cervical and paraaortic lymphadenopathy, hepatosplenomegaly, diffuse mural thickening of duodenal and jejunal loops, and bilateral lobulated kidneys. Subsequently, he succumbed to his illness secondary to refractory septic shock. On postmortem examination, he was diagnosed with classic Hodgkin lymphoma (lymphocyte-depleted type) involving paraaortic and mediastinal lymph nodes based on morphology and immunochemistry findings. The lymphomatous process involved the liver (causing multiacinar confluent hepatic necrosis) and spleen, both showing tuberculous foci. This autopsy case depicts an uncommon case of acute liver failure due to infiltration of the liver by LDCHL in an HIV-infected patient. The findings of angiotropism and angioinvasion establish the pathological mechanism of liver failure (hepatocellular necrosis) in such cases. lymphocytedepleted lymphocyte depleted LDCHL, , (LDCHL) CHL, CHL (CHL) IV course 40yearold yearold 40 year old noncholestatic non cholestatic fever hypodensities contrastenhanced contrast enhanced lymphadenopathy hepatosplenomegaly loops kidneys Subsequently shock examination type necrosis spleen foci HIVinfected HIV infected patient hepatocellular cases (LDCHL (CHL 4

ABSTRACT Esophageal melanocytosis is a rare entity defined by the proliferation of a melanocytic basal layer of the esophageal squamous lining and deposition of melanin in the esophageal mucosa. Esophageal melanocytosis is considered a benign entity of unknown etiology; however, it has been reported as a melanoma precursor. We report a case of esophageal melanocytosis in a diabetic and hypertensive 67-year-old male with recurrent dizziness and syncope for the past 6 months. Given his complaint of dyspepsia, he underwent an upper gastrointestinal endoscopy, in which an esophageal biopsy revealed the diagnosis of esophageal melanocytosis. The definitive diagnosis of esophageal melanocytosis can only be made by histological analysis. The histologic differential diagnoses include melanocytic nevi and malignant melanoma. Therefore, they need to be ruled out. mucosa etiology however precursor 67yearold yearold 67 year old months dyspepsia endoscopy analysis Therefore out

Abstract Primary cardiac tumors are rare. The cardiac sarcomas are the most common malignant cardiac tumors. These tumors have a dismal prognosis with an overall median survival of 25 months. Clinical features include dyspnea, arrhythmias, pericardial effusions, heart failure, and sudden cardiac death. The diagnosis is often challenging. Therefore, the cardiac imaging workup plays a central role in addition to a high clinical suspicion in the setting of atypical presentations that do not respond to standard therapies. The echocardiography, computed tomography, and cardiac MRI are crucial in clinching the diagnosis. Multimodal treatment with surgery, chemotherapy, and radiotherapy has been shown to improve outcomes, as opposed to using either of these modalities alone. We describe the case of a 30-year-old gentleman with COVID-19 infection who developed recurrent hemorrhagic pericardial effusions refractory to standard treatment and was eventually diagnosed as a case of pericardial angiosarcoma after his biopsy revealed the diagnosis and staging was performed using PET–CT–FDG scan. Our case re-emphasizes the importance of considering a malignant etiology early in the course of the disease presentation, especially in recurrent hemorrhagic effusions despite an inflammatory cytologic diagnosis of fluid. It also highlights the place for cardiac CT and MRI to ascertain the location and spread and to plan the further course of treatment. If diagnosed early, the estimated survival time can be prolonged by instituting a multimodal approach. rare 2 months dyspnea arrhythmias failure death challenging Therefore therapies echocardiography tomography surgery chemotherapy outcomes alone 30yearold yearold 30 year old COVID19 COVID 19 COVID-1 PETCTFDG PET FDG scan reemphasizes re emphasizes presentation fluid approach 3 COVID1 1 COVID-

ABSTRACT The vasa vasorum of the large pulmonary vessels is involved in the pathology of COVID-19. This specialized microvasculature plays a major role in the biology and pathology of the pulmonary vessel walls. We have evidence that thrombosis of the vasa vasorum of the large and medium-sized pulmonary vessels during severe COVID-19 causes ischemia and subsequent death of the pulmonary vasculature endothelium. Subsequent release of thrombi from the vasa interna into the pulmonary circulation and pulmonary embolism generated at the ischemic pulmonary vascular endothelium site, are the central pathophysiological mechanisms in COVID-19 responsible for pulmonary thromboembolism. The thrombosis of the vasa vasorum of the large and medium-sized pulmonary vessels is an internal event leading to pulmonary thromboembolism in COVID-19. COVID19. COVID19 COVID 19. 19 walls mediumsized medium sized COVID-1 site COVID1 1 COVID-