Comparison Approach for Identifying Missed Invasive Fungal Infections in Formalin-Fixed, Paraffin-Embedded Autopsy Specimens.

Invasive fungal infection (IFI) has a high mortality rate in patients who undergo hematopoietic stem cell transplantation, and it is often confirmed by postmortem dissection. When IFI is initially confirmed after an autopsy, the tissue culture and frozen section are challenging to secure, and in many cases, formalin-fixed, paraffin-embedded (FFPE) samples represent the only modality for identifying fungi. Histopathological diagnosis is a useful method in combination with molecular biological methods that can achieve more precise identification with reproducibility. Meanwhile, polymerase chain reaction (PCR) using fungal-specific primers helps identify fungi from FFPE tissues. Autopsy FFPE specimens have a disadvantage regarding the quality of DNA extracted compared with that of specimens obtained via biopsy or surgery. In the case of mucormycosis diagnosed postmortem histologically, we examined currently available molecular biological methods such as PCR, immunohistochemistry (IHC), and in situ hybridization (ISH) to identify fungi. It is reasonable that PCR with some modification is valuable for identifying fungi in autopsy FFPE specimens. However, PCR does not always correctly identify fungi in autopsy FFPE tissues, and other approaches such as ISH or IHC are worth considering for clarifying the broad classification (such as the genus- or species-level classification).

Histopathological study on the prevalence of trichosporonosis in formalin-fixed and paraffin-embedded tissue autopsy sections by in situ hybridization with peptide nucleic acid probe.

Trichosporon species are some of the most common pathogenic yeasts in Asia, and many are resistant to echinocandin antifungal drugs. Effective treatment of fungal infections requires the selection of appropriate antifungals and the accurate identification of the causal organism. However, in histopathological specimens Trichosporon spp. are often misidentified as Candida species due to morphological similarities. In situ hybridization (ISH) is a useful technique for identifying fungal species in formalin-fixed and paraffin-embedded (FFPE) tissue sections. Although many novel probes for ISH are available, the practical use of ISH for identification of fungi remains limited, in part due to the lack of adequate verifications. We conducted a two-center retrospective observational study in which the ISH technique was used to differentiate Trichosporon spp. and C. albicans in FFPE tissue from autopsy specimens. The study included 88 cases with blood stream yeast infection without Cryptococci extracted from 459 autopsy files of cases with proven invasive fungal infection (IFI). Positive signals for the Trichosporon spp. protein nucleic acid (PNA) probe and C. albicans PNA probe were seen for 7 and 35 cases, respectively, whereas the remaining 46 were negative for both. For the Trichosporon spp.- positive specimens, 5/7 were reported as candidiasis in autopsy records. Our results suggested that accurate histological identification of fungal infections remains challenging, but ISH may be a suitable approach to support histological findings. In addition, this retrospective study suggested that trichosporonosis may have high prevalence among cases of bloodstream yeast infections in Japan.

Neurofibromatosis type 1-associated malignant peripheral nerve sheath tumour carcinomatous pleurisy: an autopsy case.

A 57-year-old man with neurofibromatosis type 1 (NF-1) and intrathoracic meningoceles was admitted to hospital after presenting with neck pain and progressive dyspnoea. On admission, a chest computed tomography scan demonstrated right pleural effusion, neck tumour, intrathoracic meningoceles, and rib metastasis. The myelography showed no transportation between the intrathoracic meningoceles and pleural cavity. As a result, these radiological finding indicated the potential for malignant transformation. The appearance of the right pleural effusion was bloody and had no malignant cells. We biopsied the neck tumour, and the tissue showed glass-like materials but no malignant cells. At 1 month after admission, he developed bladder-rectal disorder, syndrome of inappropriate secretion of antidiuretic hormone, and paralysis of both legs and later died. An autopsy demonstrated glass-like material in the neck tumour, which was surrounded by malignant cells. NF-1 appears to have progressed to a malignant peripheral nerve sheath tumour in this patient.

Fatal Invasive Pulmonary Aspergillosis Associated with Nonspecific Interstitial Pneumonia: An Autopsy Case Report.

Invasive pulmonary aspergillosis (IPA) usually occurs in patients with severe immunodeficiencies involving neutropenia. Underlying lung disease is a well-known risk factor of IPA; however, interstitial lung disease has not been recognized as a risk factor of IPA. We herein report a patient with fibrotic nonspecific interstitial pneumonia who experienced IPA without neutropenia. His IPA was fatal and showed unusually slow disease progression over one month. The computed tomography findings showed only nonspecific consolidation and no typical lesions suggestive of IPA. Finally, the autoptic findings revealed numerous Aspergillus fungi, neutrophilic pulmonary necrosis, and vessels invaded by Aspergillus fungi.

Genomic Analysis of Single Nucleotide Polymorphisms Asp299Gly and Thr399Ile in Japanese Patients with Invasive Aspergillosis.

Single nucleotide polymorphisms (SNPs) 1063A/G (Asp299Gly) and 1363C/T (Thr399Ile) in the gene encoding Toll-like receptor 4 (TLR4) increase susceptibility to invasive aspergillosis. However, limited information is available on the prevalence of these SNPs in Japan. Therefore, we surveyed these TLR4 SNPs by using formalin-fixed and paraffin-embedded tissue blocks obtained from autopsies of patients with invasive pulmonary aspergillosis. Tissue samples of approximately 30% patients were included in genomic analysis. However, none of these samples showed the presence of TLR4 Asp299Gly and Thr399Ile polymorphisms. Thus, the present study provided information on the prevalence of TLR4 SNPs in Japanese patients with invasive aspergillosis and indicated that these SNPs played a minor role in increasing the susceptibility of Japanese individuals to invasive aspergillosis.

Comparison between the location and the histomorphological/immunohistochemical characteristics of noninvasive neoplasms of the ampulla of Vater.

To determine useful factors when selecting an appropriate procedure for noninvasive ampullary neoplasia, we investigated the relationship between the location and the histomorphological/immunohistochemical characteristics of 56 noninvasive ampullary neoplasms obtained by endoscopic papillectomy (EP). All subjects were classified according to histomorphology and location of neoplasms, and we evaluated the characteristics of each classified group using complementary immunohistochemical procedures. The CK20-positive rates of each location type were also evaluated. Subjects presented with 52 intestinal-type adenomas (low/high grade, 32:20) and 4 noninvasive pancreatobiliary papillary neoplasms (low/high grade, 1:3). Twenty-seven periampullary (peri-AMP)-type tumors and 23 extended-type tumors comprised the intestinal type, and the intra-ampullary (intra-AMP) type was composed of 4 pancreatobiliary and 2 intestinal histomorphological types. The CK20-positive rates of these 3 location types differed significantly (peri-AMP type, 50.6% ± 21.0%; extended type, 35.4% ± 18.6%; intra-AMP type, 6.9% ± 6.3%). The CK20-positive rate for intestinal-type tumors of the intra-AMP location type was lower than that of the peri-AMP location type. Intestinal-type tumors without CDX2 expression included extended and intra-AMP types, which are tumors that may show positive vertical margins when EP is performed. In this study, we found that an understanding of pancreatobiliary-type histology is an important aspect for the investigation of tumors involving the common channel of the ampulla. Furthermore, immunostaining of CDX2 and CK20 provides beneficial information if considering whether to perform an EP.

[Ten cases of advanced gastro-intestinal cancer that required preoperative dosage of PSK].

We examined ten convalescent cases of local progression digestive organ cancer, which required a radical operation after a 2-week administration of preoperative dosage of PSK. Because adjuvant chemotherapy was performed for all of the cases, 3 out of 5 advanced gastric cancer patients and 4 out of 5 advanced colorectal cancer patients had more than 5-year survival. We might be effective in controlling a host immune compromise for the lap art period, which was our aim, how long preoperative PSK dosage has contributed for the extension of survival duration. We also examined the influence of the dosage in this study in preoperational of PSK, which gave a host immune compromise by the operational aggression so far, and we reported it as well.