The application of a multidisciplinary approach in the diagnosis of Castleman disease and Castleman-like lymphadenopathies: A 20-year retrospective analysis of clinical and pathological features.

BACKGROUND: Castleman disease (CD) comprises a group of rare and heterogeneous haematological disorders, including unicentric (UCD) and multicentric (MCD) forms, the latter further subdivided into HHV8-MCD, POEMS-MCD and idiopathic-MCD (iMCD). However, according to the Castleman Disease Collaborative Network guidelines, the diagnosis of CD can only be achieved through collaboration between clinicians and pathologists. METHODS: We applied these clinical and pathological criteria and implement with clonality testing to a retrospective cohort of 48 adult and paediatric Italian patients diagnosed with reactive lymphadenitis with CD-like histological features. RESULTS: We confirmed the diagnosis of CD in 60% (29/48) of the cases, including 12 (41%) UCD and 17 (59%; five HHV8-MCD, three POEMS-MCD and nine iMCD) MCD. Of the remaining 19 cases (40%) with multiple lymphadenopathy, 5 (26%) were classified as autoimmune diseases, 1 (5%) as autoimmune lymphoproliferative disorder, 1 (5%) as IgG4-related disease, 11 (83%) as reactive lymphadenitis and 1 (5%) as nodal marginal zone lymphoma. CONCLUSIONS: Our study emphasizes the importance of the multidisciplinary approach to reactive lymphadenitis with CD-like features in order to achieve a definitive diagnosis and choose the appropriate treatment.

mTOR eosinophilic renal cell carcinoma: a distinctive tumor characterized by mTOR mutation, loss of chromosome 1, cathepsin-K expression, and response to target therapy.

In the spectrum of oncocytic renal neoplasms, a subset of tumors with high-grade-appearing histologic features harboring pathogenic mutations in mammalian target of rapamycin (mTOR) and hitherto clinical indolent behavior has been described. Three cases (2F,1 M) with histologically documented metastases (lymph node, skull, and liver) were retrieved and extensively investigated by immunohistochemistry, FISH, and next-generation sequencing. Tumors were composed of eosinophilic cells with prominent nucleoli (G3 by ISUP/WHO) arranged in solid to nested architecture. Additionally, there were larger cells with perinuclear cytoplasmic shrinkage and sparse basophilic Nissl-like granules, superficially resembling the so-called spider cells of cardiac rhabdomyomas. The renal tumors, including the skull and liver metastases, showed immunoexpression PAX8, CK8-18, and cathepsin-K, and negativity for vimentin. NGS identified mTOR genetic alterations in the three cases, including the skull and liver metastases. One patient was then treated with Everolimus (mTOR inhibitors) with clinical response (metastatic tumor shrinkage). We present a distinct renal tumor characterized by high-grade eosinophilic cells, cathepsin-K immunohistochemical expression, and harboring mTOR gene mutations demonstrating a malignant potential and showing responsiveness to mTOR inhibitors.

Acute Myeloid Leukemia with NPM1 Mutation and Disseminated Leukemia Cutis: Achievement of Molecular Complete Remission by Venetoclax/Azacitidine Combination in a Very Old Patient.

We describe a case of acute myeloid leukemia with NPM1 mutation and disseminated leukemia cutis in a very old patient, who achieved a long-lasting response to the azacitidine/venetoclax combination with molecular complete remission, given the potential value of this rarely observed clinical outcome.

Systemic ALK-negative anaplastic large cell lymphoma with distinctive myxoid change and DUSP22 rearrangement.

Systemic anaplastic lymphoma kinase-negative (ALK-) anaplastic large cell lymphoma (ALCL) comprises a genomically heterogeneous disease that is considered a distinct entity by the 2016 World Health Organization Classification of Tumours of Haematopoietic and Lymphoid Tissues. Other than lymph nodes, systemic ALK- ALCL may affect extranodal tissues, sites where the inflammatory background may be especially prominent. In this scenario, myxoid change is exceptional in systemic ALK- ALCL. We describe a rare case of systemic ALK- ALCL with distinctive myxoid changes, carrying specific chromosomal aberrations that affect the clinical outcome. Careful morphological, immunohistochemical, and molecular workup is mandatory because a myxoid background should not be a reason to ignore the possibility of a lymphoma. Finally, extensive correlation with staging and the detection of prognostic biomarkers such as DUSP22 and TP63 rearrangements are essential for the diagnosis and prediction of clinical outcome in ALK- ALCL.

An Extragenital Colonic Salpingiosis.

Endosalpingiosis is a rare condition characterized by the presence of benign fallopian tubal-like glandular epithelium derived from Mullerian ducts, usually affecting the serosal surfaces of the pelvis and peritoneum. It is histologically differentiated from endometriosis as endosalpingiosis lacks endometrial stroma. Endosalpingiosis tends to affect older women and has been associated with ovarian serous tumors of low malignant potential. The extragenital endosalpingosis is typically without symptoms, reported only once as chronic pelvic pain. It rarely affects the appendix but can be mistaken for acute appendicitis or appendiceal tumors. No reports of endoscopic findings have been never described. Its treatment is challenging and provides a multidisciplinary approach with gynecologist, surgeon and gastrointestinal endoscopist. Our case reports for the first time an endoscopic finding of colonic salpingiosis and it is challenging both for the diagnosis and for the treatment.

Case Report: Very Late, Atypical Extra-Medullary Relapse in a Patient With Acute Promyelocytic Leukemia (APL) Rescued With a Transplant-Free Approach.

Relapses of acute promyelocytic leukemia (APL) beyond 7 years from the first molecular remission are exceptional, and it is unclear whether these relapses represent a new, therapy-related leukemia rather than a delayed relapse of the original leukemic clone. The increase extra-medullary relapses (ER) in the era of all-trans retinoic acid (ATRA) therapy suggests a potential correlation between ATRA therapy and ER, and several potential explanations have been proposed. The gold standard post-remission approach, particularly for patients in late relapse, has not yet been established. The benefit of a transplant approach has been questioned in this setting because continuing ATRA-arsenic trioxide (ATO) might be curative. Here we report on the case of an APL patient who relapsed 9 years after achieving her first molecular complete remission (mCR) and who showed an atypical isolated localization at nodal sites, including the into- and peri-parotid glands. Genomic PML/RARa breakpoint analysis detected the same bcr3 PML/RARa hybrid gene in DNA purified from bone marrow and lymph nodes, suggesting that the relapse was because of the reemergence of the initial clone. This case shows that APL, treated with ATRA and cytotoxic drugs, may still emerge in extra-medullary sites even after a very prolonged mCR and could be salvaged with an ATO-based protocol, not including a transplant approach.

NPM1 Mutated, BCR-ABL1 Positive Myeloid Neoplasms: Review of the Literature.

Breakpoint cluster region - Abelson (BCR-ABL1) chimeric protein and mutated Nucleophosmin (NPM1) are often present in hematological cancers, but they rarely coexist in the same disease. Both anomalies are considered founder mutations that inhibit differentiation and apoptosis, but BCR-ABL1 could act as a secondary mutation conferring a proliferative advantage to a pre-neoplastic clone. The 2016 World Health Organization (WHO) classification lists the provisional acute myeloid leukemia (AML) with BCR-ABL1, which must be diagnosed differentially from the rare blast phase (BP) onset of chronic myeloid leukemia (CML), mainly because of the different therapeutic approach in the use of tyrosine kinase inhibitors (TKI). Here we review the BCR/ABL1 plus NPMc+ published cases since 1975 and describe a case from our institution in order to discuss the clinical and molecular features of this rare combination, and report the latest acquisition about an occurrence that could pertain either to the rare AML BCR-ABL1 positive or the even rarer CML-BP with mutated NPM1 at the onset. Differential diagnosis is based on careful analysis of genotypic and phenotypic features and anamnestic, clinical evolution, and background data. Therapeutic decisions must consider the broader clinical aspects, the comparatively mild effects of TKI therapy versus the great benefit that might bring to most of the patients, as may be incidentally demonstrated by our case history.

Germinotropic lymphoproliferative disorder: a systematic review.

Germinotropic lymphoproliferative disorder is a rare and rather enigmatic novel entity with distinctive clinicopathological features, one of which is the typical co-infection by Human herpesvirus 8 and Epstein-Barr virus. Human herpesvirus 8 is a lymphotropic virus detected in Kaposi sarcoma, multicentric Castleman disease, primary effusion lymphoma, Human herpesvirus 8-positive diffuse large B cell lymphoma not otherwise specified, and germinotropic lymphoproliferative disorder. Co-infection by Human herpesvirus 8 and Epstein-Barr virus is identified only in two lymphoproliferative diseases: germinotropic lymphoproliferative disorder and primary effusion lymphoma, which are otherwise diseases with totally different clinical presentations and outcomes. Unlike primary effusion lymphoma mostly occurring in immunocompromised individuals and following an aggressive course, germinotropic lymphoproliferative disorder usually presents with single or multiple lymphadenopathy affecting mainly immunocompetent individuals and mostly follows an indolent course. Based on the PRISMA guidelines, we carried out a systematic search on PubMed/MEDLINE, Web of Science, Scopus, EMBASE, and Cochrane Library using the search terms "germinotropic" and "lymphoproliferative disorder." Current scientific literature reports just 19 cases of germinotropic lymphoproliferative disorder. The purpose of our systematic review is to improve our understanding of the disease, focusing on epidemiology, clinical presentation, pathological features, treatment, and outcome. In addition, we discuss the differential diagnosis with the other Human herpesvirus 8-related lymphoproliferative diseases as currently recognized in the World Health Organization classification, adding a focus on lymphoproliferative disorders showing overlapping features.

The broad landscape of follicular lymphoma: Part II.

Follicular lymphoma is a neoplasm derived from follicle center B cells, typically both centrocytes and centroblasts, in variable proportions according to the lymphoma grading. The pattern of growth may be entirely follicular, follicular and diffuse and rarely completely diffuse. It represents the second most common non-Hodgkin lymphoma, after diffuse large B-cell lymphoma and it is the most common low-grade mature B-cell lymphoma in Western countries. In the majority of cases, follicular lymphoma is a nodal tumor, occurring in adults and is frequently associated with the translocation t(14;18)(q32;q21)/IGH-BCL2. However, in recent years the spectrum of follicular lymphoma has expanded and small subsets of follicular lymphoma, which differ from common follicular lymphoma, have been identified and included in the current 2017 WHO classification. The aim of our review is to describe the broad spectrum of follicular lymphoma, pointing out that the identification of distinct clinicopathological variants of follicular lymphoma is relevant for the patient outcomes and treatment.

The broad landscape of follicular lymphoma: Part I.

Follicular lymphoma is a neoplasm derived from follicle center B cells, typically both centrocytes and centroblasts, in variable proportions according to the lymphoma grading. The pattern of growth may be entirely follicular, follicular and diffuse, and rarely completely diffuse. It represents the second most common non-Hodgkin lymphoma, after diffuse large B-cell lymphoma and is the most common low-grade mature B-cell lymphoma in western countries. In the majority of cases, follicular lymphoma is a nodal tumor, occurring in adults and frequently associated with the translocation t(14;18)(q32;q21)/IGH-BCL2. However, in recent years the spectrum of follicular lymphoma has expanded and small subsets of follicular lymphoma, which differ from common follicular lymphoma, have been identified and included in the current 2017 WHO classification. The aim of our review is to describe the broad spectrum of follicular lymphoma, pointing out that the identification of distinct clinicopathological variants of follicular lymphoma is relevant for patient outcomes and choice of treatment.

ALK-negative anaplastic large cell lymphoma with "Hodgkin-like" cytomorphology and nuclear expression of PAX5.

Anaplastic lymphoma kinase negative systemic anaplastic large cell lymphoma (ALK-ALCL) is a CD30+ T-cell malignant lymphoma which may involve both lymph nodes and extranodal tissues, showing important clinical differences from ALK-positive ALCL (ALK + ALCL). ALK- ALCL is considered a specific entity by the 2016 World Health Organization (WHO) classification of hematolymphoid neoplasms.We describe an exceptional case of ALK- ALCL with a striking "Hodgkin-like" cytomorphology and a very uncommon nuclear expression of PAX5.

Evaluation of the prognostic role of tumour-associated macrophages in newly diagnosed classical Hodgkin lymphoma and correlation with early FDG-PET assessment.

In Hodgkin Lymphoma (HL), about 20% of patients still have relapsed/refractory disease and late toxic effects rate continue to rise with time. 'Early FDG-PET' and tissue macrophage infiltration (TAM) emerged as powerful prognostic predictors. The primary endpoint was to investigate the prognostic role of both early FDG-PET and TAM; the secondary endpoint was to test if early FDG-PET positivity could correlate with high TAM score. A cohort of 200 HL patients was analysed. Induction treatment plan consisted of two to six courses of ABVD and, if indicated, involved field radiation therapy. All patients repeated CT scan and FDG-PET after two cycles and after the completion of therapy. TAM in diagnostic specimens was determined by immunohistochemistry with a monoclonal antibody (anti-CD68 KP1). Overall, early FDG-PET was negative in 163 patients (81.5%) and positive in 37 patients (18.5%), showing a significant correlation with the achievement of CR (p < 0.0001). After a median follow-up of 40 months, progression free survival (PFS) was significantly better for PET negative patients (p < 0.0001). CD68 expression was low, intermediate or high in 26 (13%), 100 (50%) and 74 (37%) cases, without difference in the distribution between responders and non-responders. PFS analysis showed no significant difference in any score group. TAM score did not show any correlation with early FDG-PET result. This study confirms that early FDG-PET has a high prognostic power, while TAM score does not seem to influence the outcome; in contrast to our original hypothesis, it does not correlate with FDG-PET assessment. Copyright © 2015 John Wiley & Sons, Ltd.

Primitive "Spindle Cell Variant" (Sarcomatoid Variant) Diffuse Large B-Cell Lymphoma of the Uterine Cervix: Description and Outcome of a Rare Case.

A very rare case of primary diffuse large B-cell lymphoma of the uterine cervix characterized by "spindle cell variant" morphology ("sarcomatoid subtype") is described along with a discussion of the challenging diagnosis due to its rarity and presenting clinical and pathological features.