Shaken adult syndrome due to ocean wave: an autopsy case.

Severe intracranial trauma during torture or assault is reportedly caused by shaken adult syndrome. However, intracranial traumas caused by natural forces, excluding human factors and collision impact, are extremely rare. We report an autopsy case of shaken adult syndrome caused by ocean wave forces. A man in his 40s without any medical history was washed away by a wave during recreational fishing. He was found approximately 500 m away from the fishing point drifting on the ocean in a state of cardiopulmonary arrest and was confirmed dead, with no response to cardiopulmonary resuscitation, 3 h after the accident. The autopsy revealed no mechanical trauma to the entire body surface, including the head. Both lungs were inflated, and pleural effusion was observed. The brain was swollen and congested, and subarachnoid hemorrhage was observed in the interhemispheric fissure and the convexity of the parietal occipital lobe. Macroscopic and microscopic hemorrhage spots were found in the brain, and the results of the blood alcohol test and urinary toxicological screening were negative. The cause of death was determined as drowning. This case demonstrates a rare but notable mechanism of injury observed in immersed bodies.

Accidental carbon dioxide poisoning due to dry ice during a funeral wake: An autopsy case.

We report the autopsy case of a male in his 60 s diagnosed with carbon dioxide (CO2) poisoning caused by dry ice for cooling in a coffin during a funeral wake. He was last seen alive, clinging to his family member's body with his head inside the coffin. The autopsy and histological findings did not indicate a specific cause of death. To confirm the concentrations of CO2 and oxygen (O2) in the coffin, an experiment was conducted to reconstruct the scene. Based on the experimental results, 9 h after placing dry ice, the CO2 concentration at the estimated closest point to his head was 24%, a lethal level for CO2 poisoning. Contrastingly, although the concentration of O2 had fallen, it never reached a lethal concentration at any of the determination points during the experiment, thereby ruling out asphyxia as a cause of death. Based on our findings, we concluded that the cause of his death was CO2 poisoning. Forensic pathologists tend to overlook CO2 poisoning unless suspected, as it does not exhibit specific autopsy findings. For the diagnosis of CO2 poisoning, it is essential to collect detailed information about the deceased and the scene of death. The toxicity of CO2 itself is not well known, although dry ice is widely available to the public. In order to make its risk well known, it is necessary to inform people about the dangers of using dry ice.

Urinary phenylacetylglutamine as a possible biomarker for central nervous system disorders in forensic autopsy cases.

Phenylacetylglutamine (PAG) is a metabolite that is excreted in human urine. Phenylalanine is metabolized to phenylacetic acid, which is then amide-bonded to glutamine to form PAG. We are currently studying PAG as a urinary biomarker in forensic autopsy cases. MATERIALS AND METHODS: Urine samples were collected from 188 forensic autopsy cases and the urinary PAG concentration was analyzed quantitatively using GC-MS. Urinary creatinine (Cr) concentration was also analyzed by GC-MS. For statistical analysis, the JMP Pro 15.0.0 software program was used. The relationship between urine PAG/Cr (the ratio of each concentration), sex, age, postmortem interval (PMI), survival duration, and cause of death was statistically analyzed. RESULTS AND DISCUSSION: The median (range) of PAG/Cr was 0.12 (0.002-3.26). The PAG/Cr ratio showed no significant relationship to sex or survival duration. Regarding the cause of death, traumatic brain injuries had a significantly higher ratio than intoxication (p=0.023). Cerebrovascular disease, such as cerebral hemorrhage and subarachnoid hemorrhage, did not differ significantly from any cause of death group. However, when traumatic brain injuries and cerebrovascular accidents are combined as one cause of death group, the PAG/Cr value of CNS damages was significantly higher than that of intoxication (p=0.062). CONCLUSION: Urinary PAG/Cr might be a biomarker not only for traumatic brain injuries but also for antemortem CNS damages.

Milk of calcium pericardial effusion confirmed with postmortem computed tomography and autopsy findings: A case report.

We present the postmortem computed tomography and autopsy findings of a 60-year-old man who developed milk of calcium pericardial effusion and died of constrictive epicarditis. He experienced out-of-hospital cardiopulmonary arrest, and spontaneous circulation returned at the hospital. However, 7 h after recovery, the patient died. He had a swollen neck, had been experiencing coughing from 4 to 5 days earlier, and had no significant medical or surgical history. On computed tomography (CT), highly dense pericardial fluid (CT value: 130-150 Hounsfield units) and multiple calcifications along the epicardium and pericardium were visualized. The epicardium and pericardium were thick, hard, rough, and widely calcified with mild adhesions on autopsy. The pericardial cavity contained a pale, reddish brown, turbid, and highly viscous liquid. Bacteriological tests of pericardial fluid cultures revealed the presence of group G ß-hemolytic streptococci. Hence, we diagnosed the patient's cause of death as heart failure due to constrictive epicarditis. We believe that this case of milk of calcium pericardial effusion is the first case confirmed with postmortem CT and autopsy findings.

Organ distribution of endogenous p-cresol in hemodialysis patients.

BACKGROUND: p-Cresol concentrations are high in the blood of hemodialysis (HD) patients. However, its organ distribution has not yet been investigated in detail. We herein report the distribution of p-cresolin HD patients from forensic autopsy cases. METHODS: p-Cresol was measured in the blood, urine, lungs, liver, and kidneys from 4 HD and 4 non-HD cases. Samples were extracted with p-cresol-d8 (internal standard), derivatized,and injected on the GC-MS. RESULTS AND DISCUSSION: The total urinary p-cresol/Cr was 79.73 ng/ml in HD cases,which was 16-fold higher than that in non-HD cases. p-Cresol in the blood and kidneys were 30-fold higher or more at 11.92 and 13.08 µg/mL(g), respectively. p-Cresol in the liver and lungs were approximately 20-fold higher at 4.82 and 9.99 µg/g, respectively. p-Cresol was markedly increased in not only the blood, but also the urine and organs of HD cases. The distribution of p-cresol in the blood, urine, and organs differed between HD and non-HD cases. In HD cases, the percentages of conjugated (C) and protein-bound conjugated (PC) urinary p-cresol were 57 and 41%, respectively. C and PC p-cresol was 66% and 25% in the kidneys, respectively, and similar results were obtained in the lungs. J. Med. Invest. 66 : 81-85, February, 2019.

VNTR polymorphism in the monoamine oxidase A promoter region and cerebrospinal fluid catecholamine concentrations in forensic autopsy cases.

Monoamine oxidase A (MAOA) plays important roles in the metabolism of catecholamines and modulates adrenergic, noradrenergic, and dopaminergic signaling. A polymorphic promoter variable number tandem repeat (VNTR) locus (MAOA-uVNTR) is located approximately 1.2 kb upstream from MAOA exon 1. Functional studies revealed that MAOA-uVNTR affects gene expression. In the present study, we examined the frequencies of MAOA-uVNTR alleles in Japanese autopsy cases, in which amphetamines or psychotropic drugs were not detected. In total, 87 males and 35 females were evaluated and investigated for the possible effect of MAOA-uVNTR polymorphisms on cerebrospinal fluid (CSF) catecholamine concentrations. In males, there was no significant association between MAOA-uVNTR polymorphisms and CSF adrenaline (Adr), noradrenaline (Nad), or dopamine (DA) levels. In contrast, females who were homozygous for the 3-repeat allele (i.e., 3/3 genotype carriers) had higher CSF levels of Adr (p = 0.024) and DA (p = 0.035) than individuals who were heterozygous or homozygous for the 4-repeat allele (3/4 and 4/4, respectively). We found no significant association between MAOA-uVNTR polymorphisms and CSF Nad levels in females. Thus, the results of the present study indicated that MAOA-uVNTR polymorphism influences CSF Adr and DA levels in females.

Diagnostic meaning of blood p-cresol concentration in forensic autopsy cases.

In some forensic autopsy cases there are high concentrations of p-cresol in the blood. In vivo, p-cresol is the only isomer yielded by intestinal bacteria and is excreted into urine. We investigated the diagnostic meaning of p-cresol in the blood of forensic autopsy cases. Blood samples from 110 autopsy cases within 48 h of the postmortem interval (PMI) and 10 healthy adults were examined. Blood with p-cresol-d8 as an internal standard was analyzed using a GC-MS/MS method. Using acid and heat deproteinization, free (F) and conjugated (non-protein bound: C; protein bound: PC) p-cresol were individually analyzed. The p-cresol concentrations were 1.39 ±â€¯0.86 µg/ml [mean ±â€¯SD] and 1.18 (0.19-18.80) µg/ml [median (range)] in healthy adults and autopsy cases, respectively. The p-cresol showed no significant relationship to age, sex, fasting duration, survival duration, or PMI. No significant differences were found between causes of death. Significantly higher levels of C p-cresol were found in cases with atherosclerosis in the basilar or renal arteries, or stenosis in the coronary artery. Significantly higher levels of p-cresol except F were found in cases with hyalinosis of the kidney. Cases with low BMI also showed significantly higher p-cresol concentrations. The 22 cases of abnormally high total p-cresol were investigated. It was considered that high concentrations of p-cresol could be an indicator of certain diseases and physical conditions that effect the production, absorption, metabolism, circulation, and excretion of p-cresol. Measuring the levels of p-cresol may provide valuable information about the antemortem physical conditions.

An unusual case of suicide by methanol ingestion.

A female in her late teens purposely ingested alcohol fuel containing methanol to commit suicide, which she admitted on social media. She was found in distress by her parents and died at the hospital some hours later. Autopsy revealed swelling of the brain and edematous and congestive lungs. No other trauma or unusual findings were revealed at autopsy. Methanol was detected upon routine screening for alcohols by headspace gas chromatography with flame-ionization detection. To confirm the presence of methanol and its metabolite formic acid, a method with detection by mass spectrometry was used. Methanol and formic acid were quantitated in body fluids and tissues by headspace gas chromatography with flame-ionization detection. Formic acid was converted to isopropyl formate by reaction with isopropanol and concentrated sulfuric acid. Acetonitrile was used as the internal standard. The methanol and formic acid concentrations were analyzed in peripheral blood, heart blood, cerebrospinal fluid, liver, kidney, spleen, pancreas, lung, muscle, and fat. Successful confirmation and quantitation of methanol and formic acid, a methanol metabolite, in postmortem specimens was achieved on an uncommon case of suicide by methanol ingestion.

Association between cytochrome P450 2D6 polymorphisms and body fluid methamphetamine concentrations in Japanese forensic autopsy cases.

Methamphetamine (MA) is an illicit stimulant that affects the central nervous system. Cytochrome P450 2D6 (CYP2D6) plays an important role in MA metabolism. Numerous allelic variants confer substantial variation in CYP2D6 activity among individuals. In the present study, we examined the frequencies of CYP2D6 alleles, including CYP2D6*1, *2, *4, *5, *10, *14A, *14B, *18, and *36, and multiplication, in 82 forensic autopsy cases of MA abusers and 567 autopsy cases in which MA was not detected (controls). Ultrarapid metabolizer (UM), extensive metabolizer (EM), intermediate metabolizer (IM), and poor metabolizer (PM) phenotypes were predicted from CYP2D6 genotypes. Of MA abusers, 64 subjects were predicted to be EM, 17 were IM, and 1 was UM. No MA abuser had the predicted PM phenotype. No significant differences in CYP2D6 phenotype frequencies were found between MA abusers and controls. MA and amphetamine (AMP) concentrations were measured in the right heart blood, left heart blood, peripheral external iliac blood, urine, pericardial fluid, and bone marrow of MA abusers. MA concentrations in urine and bone marrow were significantly higher in IM than in EM. AMP concentration was not associated with CYP2D6 phenotype in any body fluid. These results suggest that the MA concentration in body fluids is influenced by CYP2D6 phenotypes in the Japanese population.

DRD2/ANKK1 gene polymorphisms in forensic autopsies of methamphetamine intoxication fatalities.

Dopamine D2 receptor/ankyrin repeat and kinase domain containing 1 (DRD2/ANKK1) gene polymorphisms have been associated with responses to psychotropic drugs and addiction. We analyzed two DRD2/ANKK1 polymorphisms, Taq1A and -141C Ins/Del, in 37 fatal methamphetamine (MA) intoxication cases and 235 control cases in which MA and psychotropic drugs were not detected. The association among polymorphism, cause of death, and cerebrospinal fluid (CSF) dopamine concentration was evaluated. The Taq1A polymorphism distribution in the fatal MA intoxication cases differed from in the controls (P = 0.030) with a significantly high A1/A1 + A1/A2 genotype frequency. No significant associations were observed between -141C Ins/Del polymorphisms and MA intoxication cases or between DRD2/ANKK1 polymorphisms and CSF dopamine concentrations. Our findings suggest that the DRD2/ANKK1 Taq1A polymorphism is associated with susceptibility to fatal MA intoxication.

Subarachnoid hemorrhage in a Japanese cocaine abuser: Cocaine-related sudden death.

Based on a prospective case-control study of forensic autopsies, the causes of cocaine (COC)-related sudden death (SD) are cardiovascular events in 62.0% of cases, cerebrovascular events in 14.0%, and others. A forensic autopsy of a male in his early forties revealed subarachnoid hemorrhage (SAH) at the base of the brain. A cerebral arterial aneurysm was not detected even though hemorrhage was clearly observed in the anterior cerebral artery (ACA) bifurcation area. The brain weighed 1488 g and was edematous. We histopathologically examined the left-ACA, right-ACA, and anterior communicating artery (Acom). Thickening of the internal vessel wall was observed as a pathological change. The internal elastic lamina of the right-ACA, near the peripheral part of Acom, was meandered with a jagged appearance. A toxicology examination detected COC and its metabolites, particularly benzoylecgonin, in blood and urine samples. Therefore, the present case was regarded as a non-fatal intoxication case, but also a COC-related death. Ethanol was also detected, indicating that COC was taken in combination with alcohol. The cause of COC-related death in the present case was SAH. COC use is known to induce aneurysmal SAH; however, whether an aneurysm had formed in the present case was unclear. Meander, extension, and degeneration of the internal elastic lamina of the right-ACA were observed near the bifurcation from the Acom. This area corresponded macroscopically with that considered to be the bleeding point from the blood vessel. Therefore, the present case was diagnosed as COC-related SD.

Tissue Distribution of Suvorexant in Three Forensic Autopsy Cases.

Suvorexant (Belsomra®) is a relatively new insomnia medication that has been available in USA and Japan since 2014. It is a dual orexin receptor antagonist that promotes sleep by inhibiting the binding of orexin neurons to the OX1R and OX2R receptors. In this report, we describe the detection and quantitation of suvorexant from the postmortem specimens of three separate autopsy cases handled by our department. Suvorexant was identified by fast gas chromatography/mass spectrometry during routine screening, and quantitated by a fully validated liquid chromatography-tandem mass spectroscopy method. Quantitation was achieved by positive electrospray ionization in the selected reaction monitoring mode. Monitored transitions were m/z 451 > 186 for quantitation and m/z 451 > 104 for qualification. To our knowledge, this is the first instance of suvorexant being quantitated from actual autopsy cases. It is likely that this compound will be encountered more often by the forensic toxicology community going forward.

Giant intracranial arteriovenous malformation as the focus of epileptic seizures.

A man in his late thirties was found in a supine position in the hallway of his house. He had been diagnosed with epilepsy at approximately 20 years old. Since stopping treatment, epileptic events occurred more frequently and his condition deteriorated in the past 2 years. Autopsy revealed that head injuries were found on the left side of his head. A fracture from the left parietal bone to the anterior cranial fossa was also detected. A subdural hemorrhage (hematoma) spanned a wide range. A subarachnoid hemorrhage was also identified in the left parietal region. His brain weighed 1603 g, was edematous, and showed right uncal herniation. In the right cerebral hemisphere, a thick, enlarged blood vessel ran from the sagittal sinus. An egg-sized tumorous lesion of blood vessels was found on the bottom of the frontal lobe. This vascular lesion had formed between the sagittal sinus and right anterior cerebral artery. Pathologically, veins and arteries were found together, and, thus, this case was diagnosed as an arteriovenous malformation (AVM). No other pathological and toxicological findings were observed. Subdural hematoma, the cause of death, occurred from the fall to the floor. An epileptic seizure may have been the cause of the fall. AVM on his brain was considered to be the focal lesion of epileptic seizures.

Basal subarachnoid hemorrhage by rupture of arteriovenous malformation at the cerebellopontine angle.

A man in his late forties had lived as a recluse for more than ten years. He was found dead in his room. At autopsy, subarachnoid hemorrhage (SAH) was detected at the base of the brain, which weighed 1333 g. The cerebellar tonsil was swollen. The cerebral ventricle was enlarged and filled with blood. A hematoma was observed in the upper part of the left side of the cerebellar hemisphere. The location and size of SAH in this case indicated that the rupture of a cerebral aneurysm (CA) had occurred; however, CA was not detected. A mass of blood vessels buried in the hematoma was observed at the left cerebellopontine angle (CPA). The vascular lesion showed round-shaped blood vessels as well as flat-shaped vessels with the appearance of veins, but with elastic fibers indicative of arteries. The lesion was considered to be the nidus and was 5-8 mm in size. Feeding arteries appeared to be from the anterior inferior cerebellar artery (AICA). However, the draining vein and anastomotic parts of the artery and vein were not confirmed. Based on these histopathological features, this vascular lesion was diagnosed as arteriovenous malformation (AVM). A differential diagnosis between AVM at CPA and CA is needed in order to identify the source of non-traumatic SAH.

Volatile Hydrocarbon Analysis in Blood by Headspace Solid-Phase Microextraction: The Interpretation of VHC Patterns in Fire-Related Incidents.

A headspace solid-phase microextraction (HS-SPME) technique was used to quantitate the concentration of volatile hydrocarbons from the blood of cadavers by cryogenic gas chromatography-mass spectroscopy. A total of 24 compounds including aromatic and aliphatic volatile hydrocarbons were analyzed by this method. The analytes in the headspace of 0.1 g of blood mixed with 1.0 mL of distilled water plus 1 µL of an internal standard solution were adsorbed onto a 100-µm polydimethylsiloxane fiber at 0°C for 15 min, and measured using a GC-MS full scan method. The limit of quantitation for the analytes ranged from 6.8 to 10 ng per 1 g of blood. This method was applied to actual autopsy cases to quantitate the level of volatile hydrocarbons (VHCs) in the blood of cadavers who died in fire-related incidents. The patterns of the VHCs revealed the presence or absence of accelerants. Petroleum-based fuels such as gasoline and kerosene were differentiated. The detection of C8-C13 aliphatic hydrocarbons indicated the presence of kerosene; the detection of C3 alkylbenzenes in the absence of C8-C13 aliphatic hydrocarbons was indicative of gasoline; and elevated levels of styrene or benzene in the absence of C3/C4 alkylbenzenes and aliphatic hydrocarbons indicated a normal construction fire. This sensitive HS-SPME method could help aid the investigation of fire-related deaths by providing a simple pattern to use for the interpretation of VHCs in human blood.

Association between cerebrospinal fluid dopamine concentrations and catechol-O-methyltransferase gene polymorphisms in forensic autopsy cases of methamphetamine abusers.

Methamphetamine (MA) is an illicit psychostimulant that stimulates the release of catecholamines from sympathetic nerve terminals and is widely abused worldwide. Since catechol-O-methyltransferase (COMT) metabolizes catecholamines and mediates adrenergic, noradrenergic, and dopaminergic signaling responses, we investigated the effects of the COMT polymorphisms rs4633 and rs4680 on cerebrospinal fluid (CSF) catecholamine concentrations in autopsies of subjects who died of drug intoxication. 28 MA abusers and 22 fatal psychotropic drug intoxication cases were evaluated. No correlations were identified between rs4633 or rs4680 polymorphisms and CSF concentrations of adrenaline (Adr), noradrenaline (Nad), or dopamine (DA) in fatal psychotropic cases. However, among MA abusers, DA concentrations in the CSF were significantly higher in those with the T allele (CT and TT) of rs4633 than in CC genotype carriers (p=0.004). Moreover, among MA abusers, DA concentrations were significantly higher in those with the A allele (GA and AA) of rs4680 than in GG genotype carriers (p=0.017). In subsequent haplotype analyses of MA abusers, a strong correlation was identified between two COMT haplotypes and CSF DA concentrations (p=0.002). However, the CSF concentrations of Adr and Nad were not associated with COMT genotypes or haplotypes. The present results indicate that rs4633 and rs4680 polymorphisms influence CSF DA concentrations and MA toxicity in MA abusers.

Quantification of immunohistochemical findings of neurofibrillary tangles and senile plaques for a diagnosis of dementia in forensic autopsy cases.

We report the quantification of immunohistochemical findings for a diagnosis of dementia in autopsy cases among older decedents. Autopsy cases were selected with the following requirements: >65yo; no head injuries, thermal injuries, or heat stroke; no intracranial lesions; and within 48h of death. Among cases that met all requirements, 10 had a clinical diagnosis of dementia were included in dementia group. Non-dementia group consisted of 38 cases without any record of dementia. To compare these groups, immunohistochemically, beta-amyloid, tau protein, gephyrin, and IL-33 were examined in five regions. Quantitative analysis was performed by collecting with image data analyzed using analysis software. Image data on tau-immunopositive neurofibrillary tangles (NFT) and beta-amyloid-positive senile plaques (SP) were photographed. Criteria for dementia were made by counting and measuring NFT and SP from image data using software. Differences in SP and NFT were effective for discriminating between the two groups. These criteria may reveal the presence and progression of dementia. Total of tau-positive NFT in Ammon's horn (AH) may be useful for diagnosing dementia. When the total is more than 41 in approximately 6mm(2) of AH, the possibility of dementia is considered. Total of beta-amyloid-positive SP in the parahippocampal gyrus (PHG) may be useful for diagnosing dementia. When the total in approximately 5mm(2) of PHG is more than 47, the possibility of dementia is considered. Immunohistochemical staining may be more useful for obtaining image data for quantification than conventional staining techniques, such as Bielschowsky-Hirano's silver staining.

Development of a preparation method to produce a single sample that can be applied to both LC-MS/MS and GC-MS for the screening of postmortem specimens.

Simple and efficient extraction methods have been developed for the screening of a wide array of drugs in postmortem autopsy specimens. Acidic and basic compounds were targeted with two extraction methods that can be applied to both GC-MS and LC-MS/MS instrumentation. The extractions were achieved by utilizing lipid-removal and solid-phase extraction cartridges while carefully monitoring the pH of the samples to ensure the adequate removal of interfering substances like lipids and amino acid derivatives. These methods were applied to actual autopsy cases, with 94 and 124 compounds detected by GC-MS and LC-MS/MS, respectively. The developed methods could easily be incorporated into a forensic laboratory's daily routine for screening many different compounds from postmortem samples.

GC-PCI-MS/MS and LC-ESI-MS/MS databases for the detection of 104 psychotropic compounds (synthetic cannabinoids, synthetic cathinones, phenethylamine derivatives).

Designer psychotropic compounds continue to be a major problem in Japan and all around the world. Electron impact mass spectrometry (GC-EI-MS) and liquid chromatography with electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) data on these compounds have been widely reported. In this report, we present a detection method that has been rarely utilized to analyze these types of compounds, gas chromatography with positive chemical ionization and tandem mass spectrometry (GC-PCI-MS/MS). We report on the development of GC-PCI-MS/MS and LC-ESI-MS/MS databases of 104 psychotropic compounds, including 32 cannabinoid derivatives, 29 cathinone derivatives, 34 phenethylamine derivatives, and several other designer compounds. Using this database, we were able to detect 5 psychotropic compounds in an actual forensic autopsy case. If GC-PCI-MS/MS is used together with the more established methods of GC-EI-MS and LC-ESI-MS/MS, we believe the forensic toxicology community could be better prepared to deal with the challenges of these ever-changing compounds.

Quantification of neuropathological findings by image data for the diagnosis of dementia in forensic autopsy cases.

The aim of the present study was to quantify neuropathological findings using image analysis software for the diagnosis of dementia in deceased who underwent forensic autopsy. Of the autopsies performed within 48 hours of death and excluding those of patients with head injury, thermal injury, heat stroke, or intracranial lesions, 8 were of autopsy cases clinically diagnosed with dementia and thus included in the dementia group (D). The non-dementia group (non-D) consisted of 6 deceased without dementia. To compare the D and non-D groups, 6 regions and 7 types of pathological findings were observed semi-quantitatively using 4 conventional stainings. Quantitative analysis of collected image data was performed using image analysis software. Semiquantitative analysis of senile plaques and neurofibrillary tangles was performed with Bielschowsky-Hirano's silver staining image data. An easy, simple, and effective quantification method of the pathological findings was achieved. However, no significant differences were observed between the two groups, and diagnosis of dementia by the quantification of pathological findings was not successful. Diagnosis of dementia using image data may be possible in future studies with an increased number of autopsies, and by utilizing staining techniques with higher specificity and sensitivity, such as immunohistochemical staining.