Biphenotypic lung carcinoma with coexpression of TTF-1 and ΔNP63/P40 within most of the same individual cells: a further case confirming poor prognosis and a review of literature.

The WHO Classification of Tumors, Thoracic Tumors, 5th edition, has outlined the use of TTF-1 and ΔNP63/P40 to discriminate between adenocarcinoma and squamous cell carcinoma. In 2015, the first description of a rare non-small cell lung carcinoma featuring co-expression of glandular and squamous differentiation within most of the same individual tumor cells was reported on, with ultrastructural and molecular demonstration of such a biphenotypic differentiation. We herein describe an additional case of this rare tumor entity, which is confirmed to be an aggressive neoplasm despite potential targets of therapy.

Clinicopathological characterisation of MTAP alterations in gastrointestinal cancers.

BACKGROUND: Methylthioadenosine phosphorylase (MTAP) is an essential metabolic enzyme in the purine and methionine salvage pathway. In cancer, MTAP gene copy number loss (MTAP loss) confers a selective dependency on the related protein arginine methyltransferase 5. The impact of MTAP alterations in gastrointestinal (GI) cancers remains unknown although hypothetically druggable. Here, we aim to investigate the prevalence, clinicopathological features and prognosis of MTAP loss GI cancers. METHODS: Cases with MTAP alterations were retrieved from The Cancer Genome Atlas (TCGA) and a real-world cohort of GI cancers profiled by next-generation sequencing. If MTAP alterations other than loss were found, immunohistochemistry was performed. Finally, we set a case-control study to assess MTAP loss prognostic impact. RESULTS: Findings across the TCGA dataset (N=1363 patients) and our cohort (N=508) were consistent. Gene loss was the most common MTAP alteration (9.4%), mostly co-occurring with CDKN2A/B loss (97.7%). Biliopancreatic and gastro-oesophageal cancers had the highest prevalence of MTAP loss (20.5% and 12.7%, respectively), being mostly microsatellite stable (99.2%). In colorectal cancer, MTAP loss was rare (1.1%), while most MTAP alterations were mutations (5/7, 71.4%); among the latter, only MTAP-CDKN2B truncation led to protein loss, thus potentially actionable. MTAP loss did not confer worse prognosis. CONCLUSIONS: MTAP alterations are found in 5%-10% of GI cancers, most frequently biliopancreatic and gastro-oesophageal. MTAP loss is the most common alteration, identified almost exclusively in MSS, CDKN2A/B loss, upper-GI cancers. Other MTAP alterations were found in colorectal cancer, but unlikely to cause protein loss and drug susceptibility.

Intraluminal carotid thrombus leading to postpartum stroke: a case study.

BACKGROUND: Intraluminal non-occlusive thrombus (ILT) is a rare cause of ischemic stroke. Although in most cases ILT is associated with arterial wall disorders, it has also been documented in patients with thrombophilic conditions. CASE REPORT: We present a case of carotid ILT in a 38-year-old puerperal woman with pregnancy-induced hypercoagulability. Following in vitro fertilization pregnancy, she experienced acute left-sided weakness 9 days after delivery. CT angiography revealed an intraluminal filling defect in the right carotid bulb, suggestive of a thrombus, along with ipsilateral MCA sub-occlusion. Mechanical thrombectomy was performed, achieving complete vessel recanalization without any endovascular intervention on the carotid ILT. Comprehensive evaluation excluded any underlying carotid vessel wall disease (such as atherosclerosis, inflammatory diseases, arterial dissection, focal dysplasia), inherited or acquired thrombophilia, and the sole prothrombotic risk factor identified was the puerperium. Histological thrombus analysis showed fibrin/platelet-rich material with significant macrophage infiltration (consistent with an intermediate/organized thrombus, suggesting potential embolization from a pre-existing carotid ILT). Anti-thrombotic treatment (acetylsalicylic acid 100 mg and enoxaparin 6000 UI) resulted in complete thrombus resolution at follow-up. CONCLUSION: ILT should be considered a potential case of embolic stroke in pregnancy or puerperium. Vessel imaging is essential for diagnosis. Histological thrombus analysis can provide insights into the pathophysiological mechanisms of stroke.

Tolerance to colibactin correlates with homologous recombination proficiency and resistance to irinotecan in colorectal cancer cells.

The bacterial genotoxin colibactin promotes colorectal cancer (CRC) tumorigenesis, but systematic assessment of its impact on DNA repair is lacking, and its effect on response to DNA-damaging chemotherapeutics is unknown. We find that CRC cell lines display differential response to colibactin on the basis of homologous recombination (HR) proficiency. Sensitivity to colibactin is induced by inhibition of ATM, which regulates DNA double-strand break repair, and blunted by HR reconstitution. Conversely, CRC cells chronically infected with colibactin develop a tolerant phenotype characterized by restored HR activity. Notably, sensitivity to colibactin correlates with response to irinotecan active metabolite SN38, in both cell lines and patient-derived organoids. Moreover, CRC cells that acquire colibactin tolerance develop cross-resistance to SN38, and a trend toward poorer response to irinotecan is observed in a retrospective cohort of CRCs harboring colibactin genomic island. Our results shed insight into colibactin activity and provide translational evidence on its chemoresistance-promoting role in CRC.

Exploring thrombus composition in cerebral venous thrombosis: the first case report with initial insights and implications for treatment advancements.

BACKGROUND: Endovascular thrombectomy (EVT) is a treatment option in patients with a cerebral venous thrombosis (CVT) who deteriorate despite anticoagulant treatment. Assessment of thrombus composition in CVT may provide insights into the pathophysiology of the disease and suggest new therapeutic strategies. CASE REPORT: A 47-year-old woman (smoking habit and estradiol/progesterone-releasing intra-uterine device) diagnosed with massive CVT underwent EVT (complete recanalization via aspiration catheter and stentriever) due to acute-onset left-sided weakness and dysarthria despite 72 h of full-dose subcutaneous low-molecular heparin. Two main reddish clots (maximum diameter 15 mm) were retrieved. Microscopic assessment showed an erythrocyte-rich thrombus (83.9% of entire thrombus surface) with layers of platelets/fibrin (lines of Zahn: 13.9% fibrin and 38.5% platelet [CD61+]). The immunological profile was dominated by neutrophils (30% MPO+), with neutrophil extracellular traps (NETs) in 1.9% of thrombus surface. T- (CD3+), B-lymphocytes (CD20+), and monocytes/macrophages (CD68+) were rather rare (2.2%, 0.7%, and 2.0% respectively). We found no evidence (0.0%) of hemosiderin and endothelial cells (CD34+). Full clinical recovery occurred prior to discharge. CONCLUSION: This is the first case report of a CVT with histologic assessment of the thrombus retrieved via EVT. Evaluating thrombi in CVT can provide key insights into disease pathophysiology and guide treatment advancements.

BCL3 rearrangements in B-cell lymphoid neoplasms occur in two breakpoint clusters associated with different diseases.

The t(14;19)(q32;q13) often juxtaposes BCL3 with immunoglobulin heavy chain (IGH) resulting in overexpression of the gene. In contrast to other oncogenic translocations, BCL3 rearrangement (BCL3-R) has been associated with a broad spectrum of lymphoid neoplasms. Here we report an integrative whole-genome sequence, transcriptomic, and DNA methylation analysis of 13 lymphoid neoplasms with BCL3-R. The resolution of the breakpoints at single base-pair revealed that they occur in two clusters at 5' (n=9) and 3' (n=4) regions of BCL3 associated with two different biological and clinical entities. Both breakpoints were mediated by aberrant class switch recombination of the IGH locus. However, the 5' breakpoints (upstream) juxtaposed BCL3 next to an IGH enhancer leading to overexpression of the gene whereas the 3' breakpoints (downstream) positioned BCL3 outside the influence of the IGH and were not associated with its expression. Upstream BCL3-R tumors had unmutated IGHV, trisomy 12, and mutated genes frequently seen in chronic lymphocytic leukemia (CLL) but had an atypical CLL morphology, immunophenotype, DNA methylome, and expression profile that differ from conventional CLL. In contrast, downstream BCL3-R neoplasms were atypical splenic or nodal marginal zone lymphomas (MZL) with mutated IGHV, complex karyotypes and mutated genes typical of MZL. Two of the latter four tumors transformed to a large B-cell lymphoma. We designed a novel fluorescence in situ hybridization assay that recognizes the two different breakpoints and validated these findings in 17 independent tumors. Overall, upstream or downstream breakpoints of BCL3-R are mainly associated with two subtypes of lymphoid neoplasms with different (epi)genomic, expression, and clinicopathological features resembling atypical CLL and MZL, respectively.

Unraveling the complexities of drug reaction with eosinophilia and systemic symptoms (DRESS): Insights into clinical, laboratory, and histopathologic features of a case series from an Italian tertiary center.

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe and potentially life-threatening drug hypersensitivity reaction. The diagnosis and management of DRESS are complicated due to its heterogeneous clinical and pathologic presentations, delayed onset of signs and symptoms, and unpredictable outcome. This retrospective study aimed to analyze cases of DRESS from a single Italian referring tertiary hospital center (Grande Ospedale Metropolitano Niguarda, Milan, Italy) with a focus on clinical features, causative drugs, histopathologic findings, and treatment. We have included 18 of 32 patients with a probable or definite diagnosis of DRESS. The study observed a slight predominance of women, with antimicrobials and allopurinol identified as the main causative drugs. Clinical manifestations varied, with a monomorphic maculopapular eruption being the most common, whereas facial edema and mucosal involvement were less frequently observed. Multiple organs were commonly affected, with liver and kidney involvement being prominent. Cardiac involvement was associated with the severity of eosinophilia. Laboratory evaluations showed elevated eosinophil levels and increased eosinophil cationic protein levels, supporting the role of eosinophils in DRESS pathogenesis. Histopathologic analysis revealed various patterns often coexisting in the same biopsy in 83% of cases, with interface dermatitis being the most frequent, followed by the perivascular pattern and the spongiotic/eczematous pattern. We observed eosinophils in the biopsy samples in about 50% of patients, and the relationship between peripheral eosinophilia and eosinophils in skin biopsies was not significant. In addition to the RegiSCAR score, age may play a role in predicting disease severity, as older patients with lower scores had poorer outcomes. The prognosis of DRESS depended on early identification, discontinuation of the causative agent, and appropriate therapy. Systemic corticosteroids were the primary treatment option.

Stevens-Johnson syndrome and toxic epidermal necrolysis: 11-year retrospective experience in a high-complexity tertiary hospital in Milan, Italy.

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe drug-induced hypersensitivity reactions characterized by widespread epidermal necrosis, mucous membrane erosions, and systemic findings. We have provided our 11-year experience from a Milan, Italy tertiary hospital managing SJS/TEN, evaluating the clinical and histopathologic features plus the impact on mortality. We retrospectively analyzed 28 patients diagnosed with SJS/TEN based on the clinical and histopathologic findings, according to the classification criteria of multiple studies. We assessed the dermatographics, comorbidities, drug history, lesion characteristics, clinical findings, treatments, blood tests, and outcomes. Severity scores (SCORTEN, Re-SCORTEN, ABCD-10) were used for treatment evaluation and mortality prediction. Data were statistically analyzed, and significant factors associated with mortality were identified. We found that among the 28 patients, 89.2% had comorbidities, mainly cardiovascular diseases, and 21.4% had autoimmune disorders. All patients had received systemic therapy (46.6% monotherapy, 53.6% combination therapy), with systemic steroids (71.4%) and intravenous immunoglobulins (67.8%) being common treatments. There were complications, including systemic infections (67.9%) and septic shock (10.7%). The overall mortality rate was 17.8%. The statistical analysis indicated that malignancy, a high ABCD-10 score, and a high neutrophil-to-lymphocyte ratio were significantly associated with mortality. The extent of affected body surface area did not correlate significantly with mortality. This study provides insights into SJS/TEN management, revealing factors influencing mortality in a high-complexity tertiary hospital setting.

Delphi expert consensus for whole slide imaging in thyroid cytopathology.

OBJECTIVE: Despite an increase in thyroid fine needle aspiration (FNA) and advances in whole slide imaging (WSI) adoption, digital pathology is still considered inadequate for primary diagnosis of these cases. Herein, we aim to validate the utility of WSI in thyroid FNAs employing the Delphi method strategy. METHODS: A panel of experts from seven reference cytology centres was recruited. The study consisted of two consecutive rounds: (1) an open-ended, free-response questionnaire generating a list of survey items; and (2) a consensus analysis of 80 selected shared WSIs from 80 cases by six investigators answering six morphological questions utilising a 1 to 5 Likert scale. RESULTS: High consensus was achieved for all parameters, with an overall average score of 4.27. The broad majority of items (84%) were ranked either 4 or 5 by each physician. Two badly scanned cases were responsible for more than half of the low-ranked (≤2) values (57%). Good to excellent (≥3) diagnostic confidence was reached in more than 95.2% of cases. For most cases (78%) WSI assessment was not limited by technical issues linked to the image acquisition process. CONCLUSION: This systematic Delphi study indicates broad consensus among participating physicians on the application of DP to thyroid cytopathology, supporting expert opinion that WSI is reliable and safe for primary diagnostic purposes.

Corrigendum: Case report: MAP2K1 K57N mutation is associated with primary resistance to anti-EGFR monoclonal antibodies in metastatic colorectal cancer.

[This corrects the article DOI: 10.3389/fonc.2022.1030232.].

Multimodal treatment with curative intent in a germline BRCA2 mutant metastatic ampullary adenocarcinoma: a case report.

BACKGROUND: Cancers of the Vater ampulla (ampullary cancers, ACs) account for less than 1% of all gastrointestinal tumors. ACs are usually diagnosed at advanced stage, with poor prognosis and limited therapeutic options. BRCA2 mutations are identified in up to 14% of ACs and, differently from other tumor types, therapeutic implications remain to be defined. Here, we report a clinical case of a metastatic AC patient in which the identification of a BRCA2 germline mutation drove a personalized multimodal approach with curative-intent. CASE PRESENTATION: A 42-year-old woman diagnosed with stage IV BRCA2 germline mutant AC underwent platinum-based first line treatment achieving major tumor response but also life-threatening toxicity. Based on this, as well as on molecular findings and expected low impact of available systemic treatment options, the patient underwent radical complete surgical resection of both primary tumor and metastatic lesions. Following an isolated retroperitoneal nodal recurrence, given the expected enhanced sensitivity to radiotherapy in BRCA2 mutant cancers, the patient underwent imaging-guided radiotherapy leading to long-lasting complete tumor remission. After more than 2 years, the disease remains radiologically and biochemically undetectable. The patient accessed a dedicated screening program for BRCA2 germline mutation carriers and underwent prophylactic bilateral oophorectomy. CONCLUSIONS: Even considering the intrinsic limitations of a single clinical report, we suggest that the finding of BRCA germline mutations in ACs should be taken into consideration, together with other clinical variables, given their potential association with remarkable response to cytotoxic chemotherapy that might be burdened with enhanced toxicity. Accordingly, BRCA1/2 mutations might offer the opportunity of personalizing treatment beyond PARP inhibitors up to the choice of a multimodal approach with curative-intent.

The clinical and pathologic spectrum of mucocutaneous reactions after COVID-19 vaccinations in three tertiary referral centers of northern Italy.

Adverse cutaneous reactions after COVID-19 vaccinations have increased, highlighting not only how SARS-CoV-2 infection but also COVID-19 vaccines may induce adverse cutaneous manifestations. We evaluated the clinical and pathologic spectrum of mucocutaneous reactions after COVID-19 vaccinations, observed consecutively within three large tertiary centers of the Metropolitan City of Milan (Lombardy), comparing our results with the currently available literature. We retrospectively reviewed medical records and skin biopsies of patients diagnosed with mucocutaneous adverse events after COVID-19 vaccinations and followed at three Italian tertiary referral centers in the Metropolitan City of Milan. One hundred twelve patients (77 women and 35 men (112 total); median age, 60 years) have been included in the present study; a cutaneous biopsy was performed in 41 cases (36%). The trunk and arms were the most involved anatomic areas. Autoimmune reactions after COVID-19 vaccinations, urticaria, morbilliform eruptions, and eczematous dermatitis have been the most commonly diagnosed disorders. Compared to the currently available literature, we performed many more histologic examinations, allowing us to make more precise diagnoses. Most of the cutaneous reactions were self-healing and/or responded to topical and systemic steroids and systemic antihistamines, thus not discouraging the general population from carrying out vaccinations, which currently have a good safety profile.

Unique Patterns of Heterogeneous Mismatch Repair Protein Expression in Colorectal Cancer Unveil Different Degrees of Tumor Mutational Burden and Distinct Tumor Microenvironment Features.

Mismatch repair (MMR) protein expression in colorectal cancer (CRC) cells is usually homogeneously retained or lost. Rare lesions may show a heterogeneous pattern of MMR protein expression. We evaluated MMR protein expression (MLH1, MSH2, MSH6, and PMS2) in 200 CRCs, identifying 3 groups with proficient MMR protein expression (MMRp), deficient MMR protein expression (MMRd), and heterogeneous MMR protein expression (MMRh). MMRh tumors were microdissected on the basis of the expression of the heterogeneous marker. DNA was extracted and subjected to targeted sequencing. RNA was purified from bulk tumors of all MMRh cases and in a control series of 15 MMRp and 10 MMRd CRCs and analyzed using the PanCancer IO 360 Panel (NanoString Technologies). Twenty-nine of the 200 cases (14.5%) were MMRd. Nine cases (4.5%) showed a heterogeneous pattern of MMR expression, with 6 tumors harboring concomitant loss of one of the other MMR proteins, thus featuring areas with double loss at immunohistochemistry (IHC) testing (MMRh double-loss cases). Four of the 6 MMRh double-loss cases were suitable for a separate sequence variant analysis of IHC double-negative and IHC single-negative components of the tumor. In all lesions, both components exhibited a high tumor mutation burden (TMB). Nevertheless, a significant increase in TMB in the double-negative components was observed (mean TMB: negative, 70 mut/Mb vs positive, 59 mut/Mb) because of a higher number of subclonal variants compared with the other component. Comparative gene expression analyses among MMRd, MMRp, and MMRh CRCs highlighted differential gene expression patterns and an increased number of tumor-infiltrating lymphocytes in MMRh lesions, which is also characterized by a substantial population of exhausted CD8+ lymphocytes. We describe a unique subgroup of CRCs showing heterogeneous expression of MMR proteins in a background of concomitant loss of one of the other markers.

Acute Promyelocytic Leukemia with del(6)(p22) and Atypical bcr2 PML::RARA Fusion Transcript: A Case Report.

More than 95% of patients with acute promyelocytic leukemia (APL) are characterized by the reciprocal translocation t(15;17)(q24;21), which involves the promyelocytic leukemia protein (PML) gene on chromosome 15 and the retinoic acid receptor-α (RARA) gene on chromosome 17, leading to the production of the PML::RARA chimeric gene. Additional chromosomal abnormalities are described in all acute myeloid leukemias and occur in approximately one-third of patients with newly diagnosed APL. Here, we report the case of de novo APL showing the classical t(15;17)(q24;q21), a deletion of the short arm of chromosome 6 (6p), and a noncanonical molecular variant of the PML::RARA transcript. Nevertheless, the patient achieved complete remission after treatment with conventional therapy with all-trans retinoic acid (ATRA) and arsenic trioxide (ATO). Notwithstanding that the molecular pathogenesis of this type of atypical variant still remains unknown, we conclude that this atypical PML::RARA bcr2 fusion gene associated with del(6p) does not seem to alter the effectiveness of combined treatment with ATRA and ATO.

Natural Language Processing to extract SNOMED-CT codes from pathological reports.

Objective: The use of standardized structured reports (SSR) and suitable terminologies like SNOMED-CT can enhance data retrieval and analysis, fostering large-scale studies and collaboration. However, the still large prevalence of narrative reports in our laboratories warrants alternative and automated labeling approaches. In this project, natural language processing (NLP) methods were used to associate SNOMED-CT codes to structured and unstructured reports from an Italian Digital Pathology Department. Methods: Two NLP-based automatic coding systems (support vector machine, SVM, and long-short term memory, LSTM) were trained and applied to a series of narrative reports. Results: The 1163 cases were tested with both algorithms, showing good performances in terms of accuracy, precision, recall, and F1 score, with SVM showing slightly better performances as compared to LSTM (0.84, 0.87, 0.83, 0.82 vs 0.83, 0.85, 0.83, 0.82, respectively). The integration of an explainability allowed identification of terms and groups of words of importance, enabling fine-tuning, balancing semantic meaning and model performance. Conclusions: AI tools allow the automatic SNOMED-CT labeling of the pathology archives, providing a retrospective fix to the large lack of organization of narrative reports.

Case Report: MAP2K1 K57N mutation is associated with primary resistance to anti-EGFR monoclonal antibodies in metastatic colorectal cancer.

Background: We aim to identify the prevalence and the role of the MAP2K1 K57N mutation in predicting resistance to anti-EGFR agents in metastatic colorectal cancer (mCRC) patients. Methods: We retrospectively reviewed tumor-based next generation sequencing (NGS) results from mCRC patients screened for enrollment in the GO40872/STARTRK-2 clinical trial between July 2019 and March 2021. Then, in patients harboring microsatellite stable (MSS) RAS and BRAF wild-type MAP2K1 mutant mCRC, we reviewed outcome to treatment with anti-EGFR monoclonal antibodies. Results: A total of 246 mCRC patients were screened. Most of them, 215/220 (97.7%), were diagnosed with MSS mCRC and 112/215 (52.1%) with MSS, RAS and BRAF wild-type mCRC. Among the latter, 2/112 (1.8%) had MAP2K1 K57N mutant mCRC and both received anti-EGFR monotherapy as third line treatment. In both patients, MAP2K1 K57N mutant tumors proved primary resistant to anti-EGFR agent panitumumab monotherapy. Of interest, one of these patients was treated with anti-EGFR agents three times throughout his course of treatment, achieving some clinical benefit only when associated with other cytotoxic agents (FOLFOX or irinotecan). Conclusion: We verified in a clinical real-world setting that MAP2K1 K57N mutation is a resistance mechanism to anti-EGFR agents in mCRC. Thus, we suggest avoiding the administration of these drugs to MSS RAS and BRAF wild-type MAP2K1 N57K mutant mCRC.

Pleural Kaposi sarcoma: an unusual clinical case.

Kaposi sarcoma is a low-grade mesenchymal tumor associated with human herpesvirus-8. Here we describe the case of a 37-year old woman, who underwent to kidney and liver transplant for congenital hepatic fibrosis and bilateral polycystic kidney, with successive immunosuppressive therapy. After 5 years from first transplant, she developed cutaneous, mucosal, pleural and nodal localizations of Kaposi sarcoma, without lung lesions. Because of an initial clinical presentation with an important nodal and pleural involvement, a diagnosis of a lymphoproliferative disease was suspected. Pathological examination of the pleural sample allowed to exclude lymphoproliferative neoplasia and was consistent with Kaposi sarcoma. Subsequently involvement of other sites was diagnosed as expression of diffuse disease. The interest of this case lays in the unusual clinical presentation which can lead to diagnostic pitfalls when evaluating pleural biopsies.