Acute acalculous cholecystitis as an early manifestation of COVID-19: case report and literature review

Background: The novel coronavirus disease 2019 (COVID-19) has rapidly spread worldwide since the outbreak in Wuhan, China, in 2019, becoming a major threat to public health. The most common symptoms are fever, dry cough, shortness of breath, but subjects with COVID-19 may also manifest gastrointestinal symptoms, and in a few cases an involvement of the gallbladder has been observed. Case report: Here we present a case of 50-year-old male with SARS-CoV-2 infection who had abdominal pain, vomiting and diarrhea without respiratory symptoms and was finally diagnosed as acute acalculous cholecystitis (AAC). Laparoscopic cholecystectomy was performed and found a gangrenous gallbladder; the real-time reverse transcription polymerase chain reaction SARS-CoV-2 nucleic acid assay of the bile was negative. We also made a review of the literature and try to understand the hypothetic role of SARS-CoV-2 in the pathogenesis of AAC. Conclusions: We highlighted that it is noteworthy to look at gastrointestinal symptoms in patients with SARS-CoV-2 infection and take into account AAC as a possible complication of COVID-19. Although more evidence is needed to better elucidate the role of the pathogenic mechanisms of the SARS-CoV-2 in AAC, it is conceivable that the hepatobiliary system could be a potential target of SARS-CoV-2.

The histomorphological and molecular landscape of colorectal adenomas and serrated lesions

The 2019 WHO classification of digestive system tumors significantly reformed the classificatory definition of serrated lesions of the colorectal mucosa and added new essential diagnostic criteria for both conventional adenomas and hereditary gastrointestinal polyposis syndromes. Histopathological examination of colorectal adenocarcinoma precursors lesions represents an important segment of daily clinical practice in a pathology department and is essential for the implementation of current colorectal adenocarcinoma secondary prevention strategies. This overview will focus on a schematic histopathological and molecular classification of precursor lesions arising within colorectal mucosa.

Global impact of the COVID-19 pandemic on cytopathology practice: Results from an international survey of laboratories in 23 countries

BACKGROUND

To the authors' knowledge, the impact of the coronavirus disease 2019 (COVID-19) pandemic on cytopathology practices worldwide has not been investigated formally. In the current study, data from 41 respondents from 23 countries were reported.

METHODS

Data regarding the activity of each cytopathology laboratory during 4 weeks of COVID-19 lockdown were collected and compared with those obtained during the corresponding period in 2019. The overall number and percentage of exfoliative and fine-needle aspiration cytology samples from each anatomic site were recorded. Differences in the malignancy and suspicious rates between the 2 periods were analyzed using a meta-analytical approach.

RESULTS

Overall, the sample volume was lower compared with 2019 (104,319 samples vs 190,225 samples), with an average volume reduction of 45.3% (range, 0.1%-98.0%). The percentage of samples from the cervicovaginal tract, thyroid, and anorectal region was significantly reduced (P < .05). Conversely, the percentage of samples from the urinary tract, serous cavities, breast, lymph nodes, respiratory tract, salivary glands, central nervous system, gastrointestinal tract, pancreas, liver, and biliary tract increased (P < .05). An overall increase of 5.56% (95% CI, 3.77%-7.35%) in the malignancy rate in nongynecological samples during the COVID-19 pandemic was observed. When the suspicious category was included, the overall increase was 6.95% (95% CI, 4.63%-9.27%).

CONCLUSIONS

The COVID-19 pandemic resulted in a drastic reduction in the total number of cytology specimens regardless of anatomic site or specimen type. The rate of malignancy increased, reflecting the prioritization of patients with cancer who were considered to be at high risk. Prospective monitoring of the effect of delays in access to health services during the lockdown period is warranted.

Urine TMPRSS2: ERG Fusion Transcript as a Biomarker for Prostate Cancer: Literature Review

Prostate cancer (PCa) is one of the most common male malignancies. Serum prostate-specific antigen (PSA) is one of the most valuable biomarkers in tumor biology and remains the standard marker in detecting and monitoring PCa. However, the high number of serum PSA false positive and false negative results make the identification of novel biomarkers extremely welcome to improve our diagnostic accuracy in detecting PCa and distinguishing the aggressive from the indolent ones. In this study, we analyzed the current role of urinary gene fusion transcripts involving v-ets erythroblastosis virus E26 oncogene homolog, commonly known as ERG, and the androgen-regulated gene transmembrane protease, serine 2 (TMPRSS2), as a biomarker for PCa. Used as a single marker, urinary TMPRSS2:ERG has low sensitivity but high specificity. However, its combination with the other urinary marker PCa antigen 3 (PCA3) has been reported to provide high specificity and sensitivity. Finally, a commercially available assay combining serum PSA with urinary PCA3 and TMPRSS2:ERG provides a 90% specificity and 80% sensitivity in diagnosing PCa. Urinary TMPRSS2:ERG also seems to be indicative of PCa aggressiveness upon biopsy. Should these findings be confirmed in larger studies, urinary TMPRSS2:ERG might become a valuable test not only for diagnosing PCa but also for distinguishing the aggressive tumors from the indolent ones.

Analysis of the IgVH genes in T cell-mediated and antibody-mediated rejection of the kidney graft

AIMS

Grafts have been shown to be sites where the alloimmune response develops in a direct interaction between the targeted tissue and the immune effectors. An important issue in renal rejection is B cell infiltrate that may contribute to the development or persistence of rejection. Analysis of gene-expression patterns also provides a window on the biology and pathogenesis of renal allograft rejection.

METHODS

To better understand the role exerted by B cells in a renal acute rejection, the authors analysed the IgVH gene repertoire in six cases of transplanted kidneys with acute T cell-mediated rejection (TCMR), three of which were associated with antibody-mediated rejection (ABMR).

RESULTS

The authors found mutated and unmutated sequences, without any evidence of clonal relationships, in all patients with TCMR alone and in two of the three cases with both acute TCMR and ABMR. The remaining patient showed glomerular inflammation and thrombosis, with diffuse C4d glomerular and peritubular capillary deposition, and hypermutated V region genes.

CONCLUSIONS

These results suggest that there is more than one pathway to the onset and perpetuation of CD20 (+) B cells infiltration in acute rejection; furthermore, the CD20 (+) B cells' clonal expansion may be responsible for a more severe pattern of ABMR, through immune-mediated tissue damage.

Rare lymphoid neoplasms coexpressing B- and T-cell antigens. The role of PAX-5 gene methylation in their pathogenesis

We report 3 cases of lymphoid neoplasms with mixed lineage features of T-, NK-, or B-cell marker expression and clonal gene rearrangement for both T-cell receptor and immunoglobulin light chain IgK. A characteristic of our cases was the lack of expression of the specific B-cell transcription factor, Pax5, which is essential for maintaining the identity and function of mature B cells during late B lymphopoiesis. In the absence of Pax5, B cells in vitro can differentiate into macrophages, dendritic cells, granulocytes, and T/NK cells. Methylation analysis of the Pax5 gene in our cases suggests that its inactivation by this epigenetic event in a committed or mature B cell, before plasma cell differentiation, may well be a common pathogenetic mechanism in mature lymphoid neoplasms with expression of multilineage antigens. In particular, case 1 may represent a mixed NK- and B-cell lineage; and cases 2 and 3 may represent mixed T and B-cell lineage, respectively. Aberrations in the DNA methylation patterns are currently recognized as a hallmark of human cancer. Cases with aberrant phenotypes require molecular analysis for lineage assignment. Studies of such cases may be helpful to better elucidate whether they represent a distinct entity with clinical, immunophenotypic, and molecular characteristics or an incidental phenomenon during malignant transformation. Interestingly, these cases were all characterized by poor clinical outcome.

Overlapping morphologic and immunophenotypic profiles in small B-cell lymphoma. A report of two cases

We present two cases of small B-cell lymphomas of particular diagnostic interest because the histological patterns were at variance with their immunophenotype. One of these lymphomas, involving the gallbladder and duodenum, showed a marginal zone lymphoma-like (MALT type) pattern of cellular infiltration with CD5 negativity but (unexpectedly) Cyclin D1 positivity. Fluorescence in situ hybridization analysis of this case was performed because of the aberrant expression of Cyclin D1, and was clearly positive for the Cyclin D1 gene translocation. The second case, occurring in a lymph node, showed the typical growth pattern of a follicular lymphoma but it had an atypical immunophenotype, namely, expression of Cyclin D1, CD10, and Bcl2 and focally Bcl6, accompanied by a lack of CD5 and CD23. The Cyclin D1 gene translocation was detected by fluorescence in situ hybridisation (FISH), whereas c-myc and Bcl2 genes translocation were absent. Numerical chromosomal changes, which were visualized for chromosomes 8, 11, and 18 could be correlated to the aberrant immunoprofile. In this context, we discuss the diagnostic value of Cyclin D1, CD5, CD23, CD10, Bcl6 markers revealed by immunohistochemistry, as well as the significance of detection by FISH of chromosomal translocations such as t(11;14) and t(14;18). The question still remains as to whether such cases should be designated as specific lymphoma entities or reported as unclassifiable and the chromosome aberration reported.

Activity of Rituximab Monotherapy in Refractory Splenic Marginal Zone Lymphoma Complicated with Autoimmune Hemolytic Anemia

We describe the case of a 61-year-old patient with refractory splenic marginal zone lymphoma and secondary autoimmune hemolytic anemia, both successfully treated with rituximab. This case demonstrates that rituximab monotherapy might also be a valid therapeutic approach in marginal zone lymphoma and autoimmune hemolytic anemia after failure of first-line treatment. Maintenance therapy, although expensive, could be useful to improve event-free survival in patients with unfavorable clinical behavior.

Kaposi's sarcoma–associated herpesvirus/human herpesvirus 8 infection in reactive lymphoid tissues: a model for KSHV/HHV-8–related lymphomas?

We set out to analyze the presence of Kaposi's sarcoma-associated herpesvirus (KSHV)/human herpesvirus 8 (HHV-8) in different neoplasms occurring in East Africa, a region characterized by a high KSHV/HHV-8 seroprevalence rate and endemic Kaposi's sarcoma (KS). Our results suggest that, in endemic regions of Africa, KSHV/HHV-8 is predominantly associated with KS, independently of HIV status. During the course of this study, other important information came to light. We found the presence of KSHV/HHV-8 in 2 cases of lymph nodes partially involved by Burkitt's lymphoma and KS and in 1 case of multicentric Castleman disease. Our immunophenotypic and molecular data seem to suggest 2 different mechanisms of viral infection are at work in lymphoid cells. On one hand, when B cells show a latent phase infection with KSHV/HHV-8, after the germinal center reaction, naive B cells become resting memory B cells, similarly to Epstein-Barr virus-infected B cells. On the other hand, when lytic genes such as vIL6 are expressed in naive B cells, they may be driven to differentiate into plasmablasts without undergoing germinal center reaction. Interestingly, among KSHV/HHV-8-positive cases, in those in which there was also lymphoma, the neoplastic cells were negative for KSHV/HHV-8. This further confirms that KSHV/HHV-8 is involved in the neoplastic transformation of only certain types of lymphoma, probably in relation to their precursor infected cell. In conclusion, the maturation stage of KSHV/HHV-8-positive B cells as well as the type of viral infection may well determine the morphological, phenotypic, and clinical characteristics of KSHV/HHV-8-associated lymphomas.

Cdk9 regulates neural differentiation and its expression correlates with the differentiation grade of neuroblastoma and PNET tumors

Cdk9 is a member of the Cdc2-like family of kinases. Its cyclin partners are members of the family of cyclin T (T1, T2a and T2b) and cyclin K. The Cdk9/Cyclin T complex appears to be involved in regulating several physiological processes. Recently, Cdk9 has been identified as a regulator of the differentiation program of several cell types, such as muscle cells, monocytes and lymphocytes, suggesting that it may have a function in controlling specific differentiative pathways. We analyzed whether Cdk9 and Cyclin T1 may be involved in the regulation of neuron and astrocyte differentiation. Cdk9 and Cyclin T1 expression levels were monitored during the differentiation program of neuroblastoma and astrocytoma cell lines. Our results suggest that Cdk9/Cyclin T1 complex may be required for neuron differentiation induced by retinoic acid, because the expression level of the complex varies during differentiation, but no significant changes were observed in its expression in the astrocytoma cell line. In addition, the expression of Cdk9 and Cyclin T1 was evaluated by immunohistochemistry in samples of neuroblastoma, PNET (Primary Neuroectodermal Tumor) and astrocytoma tumors of different grades, in order to assess whether there was a correlation between Cdk9 expression and tumor grading. Our results show that in neuroblastoma and PNET tumor samples Cdk9 is more expressed the more differentiated the tumor is. Conversely, no significant alteration of Cdk9 expression was observed in astrocytoma tumor samples of different grades, thus confirming the results obtained for the cell lines.

[Primary squamous cell carcinoma of the breast: a case report]

INTRODUCTION

Primary squamous cell carcinoma (SCC) of the breast is an extremely rare entity and it has a low incidence in comparison with all other mammary cancers.

MATERIAL AND METHODS

We describe a case of SCC of the breast in a 55 year old woman who presented with a painless mass located in the external quadrant of the left breast. The neoformation, once removed, was tamponate formalin fixed and routinely processed for inclusion in paraffin. Sections were stained with haematoxilin-eosin and immunohistochemical and electron microscopy investigations were performed.

RESULTS

Histologically, the neoplasia was characterized by cystic cavities covered by nests and sheaths of poorly differentiated squamous cells with keratinized areas. Mitotic activity was high, as well as cellular proliferative index, evaluated by Mib-1 (ki 67) antibody. At immunohistochemistry, the tumor cells were diffusely positive for high molecular weight cytokeratins and c-erbB-2, negative for vimentin, estrogen and progesterone. CD68 and LCA were positive only in the inflammatory cells. Electron microscopy confirmed the epithelial nature of the neoplastic cells. A diagnosis of SCC of the breast was made, and a radical mastectomy was performed.

CONCLUSIONS

We make a brief review of the literature and discuss the main histologic criteria for the differential diagnosis with adenocarcinoma of the breast with squamous metaplasia.