EBV-Driven Lymphoproliferative Disorders and Lymphomas of the Gastrointestinal Tract: A Spectrum of Entities with a Common Denominator (Part 3)

EBV is the first known oncogenic virus involved in the development of several tumors. The majority of the global population are infected with the virus early in life and the virus persists throughout life, in a latent stage, and usually within B lymphocytes. Despite the worldwide diffusion of EBV infection, EBV-associated diseases develop in only in a small subset of individuals often when conditions of immunosuppression disrupt the balance between the infection and host immune system. EBV-driven lymphoid proliferations are either of B-cell or T/NK-cell origin, and range from disorders with an indolent behavior to aggressive lymphomas. In this review, which is divided in three parts, we provide an update of EBV-associated lymphoid disorders developing in the gastrointestinal tract, often representing a challenging diagnostic and therapeutic issue. Our aim is to provide a practical diagnostic approach to clinicians and pathologists who face this complex spectrum of disorders in their daily practice. In this part of the review, the chronic active EBV infection of T-cell and NK-cell type, its systemic form; extranodal NK/T-cell lymphoma, nasal type and post-transplant lymphoproliferative disorders are discussed.

What Do We Have to Know about PD-L1 Expression in Prostate Cancer? A Systematic Literature Review. Part 2: Clinic-Pathologic Correlations

Many studies have investigated the potential prognostic and predictive role of PD-L1 in prostatic carcinoma (PC). We performed a systematic literature review (PRISMA guidelines) to critically evaluate human tissue-based studies (immunohistochemistry, molecular analysis, etc.), experimental research (cell lines, mouse models), and clinical trials. Despite some controversial results and study limitations, PD-L1 expression by tumor cells may be related to clinic-pathologic features of adverse outcome, including advanced tumor stage (high pT, presence of lymph node, and distant metastases), positivity of surgical margins, high Grade Group, and castration resistance. Different PD-L1 positivity rates may be observed in matched primary PCs and various metastatic sites of the same patients. Over-fixation, type/duration of decalcification, and PD-L1 antibody clone may influence the immunohistochemical analysis of PD-L1 on bone metastases. PD-L1 seemed expressed more frequently by castration-resistant PCs (49%) as compared to hormone-sensitive PCs (17%). Some series found that PD-L1 positivity was associated with decreased time to castration resistance. Treatment with ipilimumab, cyclophosphamide/GVAX/degarelix, or degarelix alone may increase PD-L1 expression. Correlation of PD-L1 positivity with overall survival and outcomes related to tumor recurrence were rarely investigated; the few analyzed series produced conflicting results and sometimes showed limitations. Further studies are required. The testing and scoring of PD-L1 should be standardized.

Gastrointestinal Manifestations in Systemic Mastocytosis: The Need of a Multidisciplinary Approach

Simple Summary

Mastocytosis is a group of neoplastic mast cell disorders ranging from a skin-limited disease to a systemic form with multi-organ involvement, including gut involvement. Clinical manifestations and outcome of systemic mastocytosis are variable. Symptoms may result from either release of mast cell mediators or tissue infiltration by mast cell proliferation. Gastrointestinal symptoms are one of the major causes of morbidity in these patients. The diagnosis of gastrointestinal mastocytosis can be tricky, as symptoms often mimic other more common gastrointestinal diseases; the endoscopic appearance is often unremarkable or nonspecific and the infiltrate can be focal and subtle and easily missed unless special stains are used. This review aims to better define the gastrointestinal involvement in systemic mastocytosis, discussing potential diagnostic pitfalls and pointing out the importance of a multidisciplinary approach for a prompt diagnosis and treatment.

Abstract

Mastocytosis represents a heterogeneous group of neoplastic mast cell disorders. The basic classification into a skin-limited disease and a systemic form with multi-organ involvement remains valid. Systemic mastocytosis is a disease often hard to diagnose, characterized by different symptoms originating from either the release of mast cell mediators or organ damage due to mast cell infiltration. Gastrointestinal symptoms represent one of the major causes of morbidity, being present in 60–80% of patients. A high index of suspicion by clinicians and pathologists is required to reach the diagnosis. Gastrointestinal mastocytosis can be a challenging diagnosis, as symptoms simulate other more common gastrointestinal diseases. The endoscopic appearance is generally unremarkable or nonspecific and gastrointestinal mast cell infiltration can be focal and subtle, requiring an adequate sampling with multiple biopsies by the endoscopists. Special stains, such as CD117, tryptase, and CD25, should be performed in order not to miss the gastrointestinal mast cell infiltrate. A proper patient’s workup requires a multidisciplinary approach including gastroenterologists, endoscopists, hematologists, oncologists, and pathologists. The aim of this review is to analyze the clinicopathological features of gastrointestinal involvement in systemic mastocytosis, focusing on the relevance of a multidisciplinary approach.

Persistent Response and Prolonged Survival Following Pembrolizumab Discontinuation Due to Long-Lasting Autoimmune Colitis in Advanced NSCLC: A Case Report

Pembrolizumab is a programmed death receptor-1 (PD-1) inhibitor that has been approved for treatment of a wide variety of malignancies including non-small-cell lung cancer (NSCLC). Immune-mediated colitis is a known adverse effect of pembrolizumab which can lead to the treatment interruption, although not compromising the control of the oncological disease. Herein, we report the case of a 59-year-old woman on pembrolizumab for advanced NSCLC which developed a severe and persistent colitis treated with infliximab for several months following anti-PD-1 antibody discontinuation. This strategy resulted in an improvement but not complete recovery of the gastrointestinal toxicity despite revealed sustained response and control of the oncological disease with prolonged survival over 24 months.

How Can We Treat Vulvar Carcinoma in Pregnancy? A Systematic Review of the Literature

According to our systematic literature review (PRISMA guidelines), only 37 vulvar squamous cell carcinomas (VSCCs) were diagnosed during pregnancy (age range: 17-41 years). The tumor size range was 0.3-15 cm. The treatment was performed after (14/37, 38%), before (10/37, 27%), or before-and-after delivery (11/37, 30%). We found that 21/37 (57%) cases were stage I, 2 II (5%), 11 III (30%), and 3 IVB (8%). HPV-related features (condylomas/warts; HPV infection; high-grade squamous intraepithelial lesion) were reported in 11/37 (30%) cases. We also found that 9/37 (24%) patients had inflammatory conditions (lichen sclerosus/planus, psoriasis, chronic dermatitis). The time-to-recurrence/progression (12/37, 32%) ranged from 0 to 36 (mean 9) months. Eight women died of disease (22%) 2.5-48 months after diagnosis, 2 (5%) were alive with disease, and 23 (62%) were disease-free at the end of follow-up. Pregnant patients must be followed-up. Even if they are small, newly arising vulvar lesions should be biopsied, especially in women with risk factors (HPV, dermatosis, etc.). The treatment of VSCCs diagnosed in late third trimester might be delayed until postpartum. Elective cesarean section may prevent vulvar wound dehiscence. In the few reported cases, pregnancy/fetal outcomes seemed to not be affected by invasive treatments during pregnancy. However, clinicians must be careful; larger cohorts should define the best treatment. Definite guidelines are lacking, so a multidisciplinary approach and discussion with patients are mandatory.

Oral plasmablastic lymphoma: A case report

INTRODUCTION

Plasmablastic lymphoma (PBL) is an uncommon and aggressive large B-cell lymphoma commonly diagnosed in human immunodeficiency viruses -positive patients. Oral cavity is the most commonly PBL affected site. Most oral PBLs presented as asymptomatic swellings, frequently associated with ulcerations and bleeding. Most cases lacked B-symptoms, suggesting a more local involvement of the disease. No standard treatment is yet for oral PBL. Five-year survival rate recorded no more than 33.5%.

PATIENT CONCERNS

A 39-year-old male presented to Dental Clinic with 1 month swelling of the oral cavity, in absence of any other symptoms or signs. He followed antibiotic therapy just on suspicion of an oral abscess and later oral surgical treatment on suspicion of bone neoplasm.

DIAGNOSIS

Surgical specimen analysis highlighted a diffuse infiltrate of large-sized atypical cells with plasmablastic appearance and plasma cell phenotype. Oral cavity PBL was diagnosed. Blood tests recorded mild lymphopenia and positive human immunodeficiency viruses serology.

INTERVENTIONS

Patient underwent chemotherapy including intrathecal methotrexate prophylaxis, in addition to a highly active antiretroviral therapy.

OUTCOMES

At 12 months from diagnosis, patient recorded complete hematological remission.

CONCLUSIONS

Oral PBL diagnosis requires a high level of suspicion and awareness both by physicians and pathologists. They should be aware of the extent of such disease which is often mistaken as oral abscess or infected tooth, thus leading to delay the most appropriate diagnostic evaluation. As PBL is an aggressive non-Hodgkin lymphoma, a delayed diagnosis might negatively impact on both treatment and survival.

Acute Radiation Colitis after Preoperative Short-Course Radiotherapy for Rectal Cancer: A Morphological, Immunohistochemical and Genetic Study

Preoperative radiotherapy is a widely accepted treatment procedure in rectal cancer. Radiation-induced changes in the tumor are well described, whereas less attention has been given to the non-neoplastic mucosa. Our aim is to provide a detailed analysis of the morphological features present in non-neoplastic mucosa that pathologists need to be familiar with, in order to avoid misdiagnosis, when evaluating rectal cancer specimens of patients preoperatively treated with radiotherapy, especially with short-course regimen. We compared 2 groups of 95 rectal cancer patients treated preoperatively with either short-course (45 patients) or long-course radiotherapy (50 patients). Depending on the type of protocol, different histopathological features, in terms of inflammation, glandular abnormalities and endocrine differentiation were seen in the non-neoplastic mucosa within the irradiated volume. Of note, features mimicking dysplasia, such as crypt distortion, nuclear and cytoplasmic atypia of glandular epithelium, were identified only in the short-course group. DNA mutation analysis, using a panel of 56 genes frequently mutated in cancer, and p53 immunostaining were performed on both tumor and radiation-damaged mucosa in a subset of short course cases. Somatic mutations were identified only in tumors, supporting the concept that tissues with radiation-induced "dysplastic-like" features are not genetically transformed. Pathologists should be aware of the characteristic morphological changes induced by radiation. The presence of features simulating dysplasia in the group treated with short-course radiotherapy may lead to serious diagnostic mistakes, if erroneously interpreted. Next generation sequencing (NGS) analysis further validated the morphological concept that radiation-induced abnormalities do not represent pre-neoplastic lesions.

A tricky and rare cause of pulmonary eosinophilia: myeloid/lymphoid neoplasm with eosinophilia and rearrangement of PDGFRA

Background

Eosinophilic lung diseases represent a heterogeneous group of disorders with prominent infiltrate of eosinophils in lung interstitium and alveolar spaces. Peripheral blood eosinophilia is often present. Infections, drugs, allergens, toxic agents have to be evaluated as possible causes of eosinophilic lung infiltrates. The category of myeloid/lymphoid neoplasms with eosinophilia and rearrangement of PDGFRA, PDGFRB, FGFR1 and PCM1-JAK2 represents an uncommon cause of eosinophilic lung infiltrate.

Case presentation

We report the case of a 70-year old man complaining of dry cough and dyspnea. Ground glass-opacities were seen on imaging studies and peripheral blood eosinophilia was present. A thorough step-wise patient’s evaluation led to identify the clonal nature of eosinophilia and the diagnosis of myeloid/lymphoid neoplasm with eosinophilia and rearrangement of PDGFRA was made.

Conclusions

Correlation with clinical history, laboratory tests and imaging studies is essential to achieve the correct diagnosis when facing with eosinophilic lung infiltrates. A prolonged eosinophilia can cause life-threatening organ damage. Identification of PDGFRA rearrangement, as in the present case, is particularly critical given the sensitivity and excellent response to imatinib, which has completely changed the natural history of this neoplasm.

Fibrin-associated large B-cell lymphoma: first case report within a cerebral artery aneurysm and literature review

Background

Fibrin-associated diffuse large B-cell lymphoma (FA-DLBCL) is a rare Epstein-Barr virus (EBV) positive lymphoproliferative disorder included in the current World Health Organization (WHO) classification. It arises within fibrinous material in the context of hematomas, pseudocysts, cardiac myxoma or in relation with prosthetic devices. In these clinical settings the diagnosis requires an high index of suspicion, because it does not form a mass itself, being composed of small foci of neoplastic cells. Despite overlapping features with diffuse large B-cell lymphoma associated with chronic inflammation, it deserves a separate classification, being not mass-forming and often following an indolent course.

Case presentation

A 64-year-old immunocompetent woman required medical care for cerebral hemorrhage. Computed Tomography (CT) angiography identified an aneurysm in the left middle cerebral artery. A FA-DLBCL was incidentally identified within thrombotic material in the context of the arterial aneurysm. After surgical removal, it followed a benign course with no further treatment.

Conclusions

The current case represents the first report of FA-DLBCL identified in a cerebral artery aneurysm, expanding the clinicopathologic spectrum of this rare entity. A complete literature review is additionally made.

Management of duodenal stump fistula after gastrectomy for malignant disease: a systematic review of the literature

Background

Duodenal stump fistula (DSF) remains one of the most serious complications following subtotal or total gastrectomy, as it endangers patient’s life. DSF is related to high mortality (16–20%) and morbidity (75%) rates. DSF-related morbidity always leads to longer hospitalization times due to medical and surgical complications such as wound infections, intra-abdominal abscesses, intra-abdominal bleeding, acute pancreatitis, acute cholecystitis, severe malnutrition, fluids and electrolytes disorders, diffuse peritonitis, and pneumonia. Our systematic review aimed at improving our understanding of such surgical complication, focusing on nonsurgical and surgical DSF management in patients undergoing gastric resection for gastric cancer.

Methods

We performed a systematic literature review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA) guidelines. PubMed/MEDLINE, EMBASE, Scopus, Cochrane Library and Web of Science databases were used to search all related literature.

Results

The 20 included articles covered an approximately 40 years-study period (1979–2017), with a total 294 patient population. DSF diagnosis occurred between the fifth and tenth postoperative day. Main DSF-related complications were sepsis, abdominal abscess, wound infection, pneumonia, and intra-abdominal bleeding. DSF treatment was divided into four categories: conservative (101 cases), endoscopic (4 cases), percutaneous (82 cases), and surgical (157 cases). Length of hospitalization was 21–39 days, ranging from 1 to 1035 days. Healing time was 19–63 days, ranging from 1 to 1035 days. DSF-related mortality rate recorded 18.7%.

Conclusions

DSF is a rare but potentially lethal complication after gastrectomy for gastric cancer. Early DSF diagnosis is crucial in reducing DSF-related morbidity and mortality. Conservative and/or endoscopic/percutaneous treatments is/are the first choice. However, if the patient clinical condition worsens, surgery becomes mandatory and duodenostomy appears to be the most effective surgical procedure.

Gastrointestinal Mastocytosis: A Potential Diagnostic Pitfall to Be Aware

Mastocytosis is a rare and heterogeneous group of disorders that may be limited to the skin and even spontaneously regress or may have a systemic presentation with multi-organ involvement and poor outcome. Among the extracutaneous sites, gastrointestinal tract is often affected, but nonspecific clinical manifestations combined with subtle histological findings of the disease makes the diagnosis of gastrointestinal mastocytosis rather hard. In absence of a high index of suspicion, gastrointestinal involvement is easily overlooked. We report a challenging case of systemic mastocytosis presenting with isolated gastrointestinal manifestations without skin involvement, in which the diagnosis was missed at first evaluation of intestinal biopsies.

Laparoscopic approach to an incidentally found pelvic retroperitoneal liposarcoma: Case report and review

RATIONALE

Well-differentiated liposarcomas (WDLPS) are rare retroperitoneal tumors that can reach significant size as they can grow without constrains before becoming symptomatic. Laparotomic open radical tumor resection represents the most common surgical approach.

PATIENT CONCERNS

A mass with "fat fluid level" was found in the right pelvis of an asymptomatic woman undergoing routine transvaginal ultrasound: the preoperative diagnosis was right mature ovarian teratoma.

DIAGNOSIS

Postoperative histopathology confirmed the diagnosis of WDLPS.

INTERVENTIONS

A radical laparoscopic excision of the retroperitoneal mass with bilateral salpingectomy was performed.

OUTCOMES

Patient is free of disease at 18 months after surgery.

LESSON

Despite computed tomography scan is the gold standard technique to identify WDLPS, such neoplasms can be misdiagnosed for mature ovarian teratomas. When a retroperitoneal mass is incidentally discovered during a surgery, an open core-needle biopsy is usually performed, and appropriate treatment planned only after complete staging and final pathology are available. Instead, when tumor margins are identified, resection of an incidentally diagnosed WDLPS would benefit from laparoscopic magnification that could improve distinguishing the disease from the surrounding tissues. Therefore, laparoscopy could represent a safe and effective technique to diagnose and treat retroperitoneal diseases.

Intravascular NK/T-cell lymphoma, Epstein-Barr virus positive with multiorgan involvement: a clinical dilemma

Background

Intravascular lymphoma is a rare type of non-Hodgkin lymphoma mostly of B-cell lineage. A few cases of intravascular lymphoma have been found to be of NK/T-cell origin, mainly affecting the skin and central nervous system.

Case presentation

A 54-year-old Caucasian man sought care because of a 2 weeks history of jaundice and intermittent fever, not responsive to antibiotics and antipyretics. Laboratory tests showed low blood oxygen concentration and pancytopenia. Serum microbiological tests were negative. Computerized tomography (CT) scan revealed hepatosplenomegaly and diffuse ground-glass opacities in both lungs without interlobular septal thickening. Despite oxygen therapy, the clinical conditions rapidly deteriorated leading to death 3 days after admission. Autopsy revealed a multiorgan involvement by an Epstein-Barr virus positive NK/T-cell lymphoma, strikingly growing within the blood vessel lumina, in absence of skin lesions.

Conclusions

The current case highlights the pathological features of this rare entity, the protean clinical presentation of which is often misleading, resulting in delayed diagnosis and treatment.

Erdheim-Chester disease: description of two illustrative cases involving the lung

AIM

Erdheim-Chester disease represents a clonal systemic proliferation of histiocytes. Bone is the most common site of involvement, although almost any organ, including the lungs, can be affected.

METHODS AND RESULTS

The diagnosis of Erdheim-Chester disease can be difficult, owing to its rarity and protean presentation. Correlation between clinical, radiological and histological findings is mandatory for identification of the disease. Foamy histiocytes, lacking Langerhans cell markers, represent the typical histological findings, although their absence does not rule out Erdheim-Chester disease. Identification of BRAF mutation can be helpful in making the diagnosis, and allows for the development and application of targeted therapies in this setting.

CONCLUSIONS

Herein, we describe two cases presenting with lung involvement and vertebral lesions, lacking the more typical long-bone involvement. One case histologically mimicked Rosai-Dorfman disease. However, both cases harboured the pathognomonic BRAFV600E mutation.

Colonic perforation due to severe cytomegalovirus disease in granulomatosis with polyangiitis after immunosuppression

Granulomatosis with polyangiitis (GPA) is a small-vessel necrotizing granulomatous vasculitis typically involving upper airways, lungs, and kidneys, which may lead to end-organ damage and life-threatening complications. Major infections during GPA course represent a considerable concern in the management of the disease. Cytomegalovirus (CMV) infection and disease are rare but significant complications in the course of GPA being associated with high morbidity and mortality rates. Colonic perforation due to CMV colitis is exceedingly rare and has so far almost exclusively been documented in HIV, renal transplant, and systemic lupus erythematosus patients. We reported the case of a patient affected with upper airways-limited GPA who developed acute renal failure from rapidly progressive glomerulonephritis and then experienced colonic perforation due to CMV colitis a few weeks after immunosuppressive treatment with high-dose steroids and cyclophosphamide (CYC) for remission induction of the disease. We also reviewed the literature on CMV-related gastro-intestinal complications in the course of GPA and discussed contributing factors to severe manifestations of CMV infection and its reactivation.

A Case of Moderate Sprue-Like Enteropathy Associated With Telmisartan

Sprue-like enteropathy associated with olmesartan medoxomil use has been recently reported. Its clinical manifestations include diarrhea, weight loss and malabsorption. Duodenal biopsies show villous atrophy (VA) with or without intraepithelial lymphocytosis and inflammation of the lamina propria. Serology for celiac disease (CD) is negative and gluten-free diet does not result in clinical improvement. Symptoms resolve after olmesartan discontinuation. Follow-up biopsies show recovery/improvement of the duodenum. Whether sprue-like enteropathy is a specific adverse reaction to olmesartan or rather a class effect of angiotensin-receptor blockers (ARBs) remains a controversial issue. We report a case of sprue-like enteropathy associated with telmisartan. A 52-year-old man presented with chronic diarrhea, abdominal discomfort and significant weight loss. In the last 3 years, he had been treated with telmisartan 40 mg/day for hypertension after right adrenalectomy for an aldosterone-producing adenoma. Laboratory investigations showed no significant abnormalities: Hb 13.6 g/dL, serum albumin 3.9 g/dL, total cholesterol 193 mg/dL, serum creatinine 0.99 mg/dL, sodium 143.6 mmol/L, K⁺ 4.3 mmol/L, calcium 9.3 mg/dL, phosphorus 3.9 mg/dL and 25-OH-D3 27.7 ng/mL. Duodenal histology showed subtotal VA and inflammation of the lamina propria. CD serology was negative. HLA-DQ typing showed absence of the DQ2/DQ8 haplotypes. After telmisartan discontinuation, patient’s symptoms subsided, and his body weight increased despite persistence of a gluten-containing diet. Follow-up biopsies at 3 showed progressive duodenal recovery. Very few cases of sprue-like enteropathy associated with ARBs other than olmesartan have been reported. Our case of telmisartan-associated enteropathy further suggests that sprue-like disease may be a class effect of ARBs.

Primary histiocytic sarcoma presenting as diffuse leptomeningeal disease: Case description and review of the literature

Histiocytic sarcoma is a rare malignant neoplasm arising most commonly in lymph nodes, intestinal tract, skin and soft tissue. The incidence of primary CNS histiocytic sarcoma is even rarer with a total of just 27 cases reported in the literature so far. Herein we describe the first autopsy case of histiocytic sarcoma presenting as a diffuse leptomeningeal disease in absence of a CNS tumor-forming parenchymal lesion. The clinical, pathological and immunophenotypic features are described and an updated literature review on primary CNS histiocytic sarcoma is included.

An Italian case of intestinal anisakiasis with a presurgical diagnosis: Could this parasite represent an emerging disease?

Anisakiasis is a parasitic infection caused by the consumption of raw fish containing larvae of the Anisakis species. Since the first description in 1960 of a patient suffering from this pathogen, in the Netherlands, most of the cases have been reported in Japan, where consumption of raw fish is common, but the number of cases is increasing worldwide. The first case identified in Italy dates back to 1996 and a few cases have been reported since then. In Italy the intestinal form occurs almost as frequently as the gastric form, which is far more frequent in Japan. Intestinal Anisakiasis represents a diagnostic challenge as it is clinically misdiagnosed and most of the patients require surgery due to the occurrence of complications such as bowel occlusion or perforation. Practically no cases of the intestinal form are diagnosed preoperatively. We report the first case, to our knowledge, of intestinal Anisakiasis in which surgery was avoided, due to a prompt diagnosis suspected on intestinal biopsies. A literature review of Anisakiasis cases reported in Italy is also carried out.

Alveolar Adenoma of the Lung: A Clinicopathologic, Immunohistochemical, and Molecular Study of an Unusual Case

We describe an alveolar adenoma of the lung with 3 previously unreported findings, which expand both the clinical and the morphologic spectrum of this rare tumor: presentation as a cystic nodule, foci of mature adipocytes, and S-100 positivity of the mesenchymal cells. Furthermore, using a laser capture microdissection technique under microscope visualization, we analyzed multiple chromosomal loci in both the epithelial and mesenchymal components of the lesion, showing microsatellite alterations and loss of heterozygosity in the former but not in the latter.

RIN2 syndrome: Expanding the clinical phenotype

Biallelic defects in the RIN2 gene, encoding the Ras and Rab interactor 2 protein, are associated with a rare autosomal recessive connective tissue disorder, with only nine patients from four independent families reported to date. The condition was initially termed MACS syndrome (macrocephaly, alopecia, cutis laxa, and scoliosis), based on the clinical features of the first identified family; however, with the expansion of the clinical phenotype in additional families, it was subsequently coined RIN2 syndrome. Hallmark features of this condition include dysmorphic facial features with striking, progressive facial coarsening, sparse hair, normal to enlarged occipitofrontal circumference, soft redundant and/or hyperextensible skin, and scoliosis. Patients with RIN2 syndrome present phenotypic overlap with other conditions, including EDS (especially the dermatosparaxis and kyphoscoliosis subtypes). Here, we describe a 10th patient, the first patient of Caucasian origin and the oldest reported patient so far, who harbors the previously identified homozygous RIN2 mutation c.1878dupC (p. (Ile627Hisfs*7)). Besides the hallmark features, this patient also presents problems not previously associated with RIN2 syndrome, including cervical vertebral fusion, mild hearing loss, and colonic fibrosis. We provide an overview of the clinical findings in all reported patients with RIN2 mutations and summarize some of the possible pathogenic mechanisms that may underlie this condition. © 2016 Wiley Periodicals, Inc.

Malakoplakia Associated With Multiple Adenomas of the Colon: An Extremely Rare Incidental Finding

Malakoplakia in the colon has been described either as part of a systemic disease with a diffuse presentation or as a rare incidental finding associated usually with an adenocarcinoma. To our knowledge, the association of malakoplakia with colonic adenoma is very rare and only 5 cases, including the present case, have been reported so far. Here, we describe a case of malakoplakia coexisting with multiple sigmoid colonic adenomas in a 67-year-old patient without any underlying inflammatory or infectious disease and with no history of immunosuppressive treatment. As far as we are concerned, this is the first description of malakoplakia associated with multiple colonic adenomas.

Large cell neuroendocrine carcinoma of the ampulla of vater

We report a large cell neuroendocrine carcinoma arising in the ampulla of Vater. The patient, a 74-year-old woman, presented with a 3-cm ulcerated mass located in the ampullary region. She died of disease 8 months after surgery. Microscopically, the tumor was extensively necrotic. It was composed of islands and trabeculae irregularly infiltrating the muscular wall of the duodenum. Neoplastic cells were large and had a high mitotic index. Immunohistochemically, they expressed cytokeratin, chromogranin, synaptophysin, and neuron-specific enolase. Large cell neuroendocrine carcinoma is very rare in the ampulla of Vater, and it shares with its more common pulmonary counterpart the same morphology and probably the same poor prognosis.

Sclerosing haemangioma with a predominant sclerotic pattern: an unusual pulmonary lesion which can be misdiagnosed

AIMS

An unusual sclerosing haemangioma of the lung with a predominant sclerotic pattern is described.

MAIN RESULTS AND CONCLUSIONS

The patient was a 51-year-old male, presenting with a well-circumscribed nodule, 0,6 cm in diameter, located in the lower lobe of the left lung. He is alive and well 9 years after surgical excision of the nodule. Microscopically, the lesion was well demarcated and mostly composed of sclerotic tissue, with numerous irregular entrapped alveolar spaces The characteristic bland, round cells with abundant pale cytoplasm, immunohistochemically positive for TTF-1 and negative for cytokeratin, were limited to small clusters embedded in the stroma at the periphery of the nodule. The most important differential diagnostic considerations of the sclerotic variant of pulmonary sclerosing haemangioma are briefly discussed.

Characterization of the initial alpha-thrombin interaction with glycoprotein Ib alpha in relation to platelet activation

We have evaluated the properties of alpha-thrombin interaction with platelets within 1 min from exposure to the agonist, a time frame during which most induced activation responses are initiated and completed. Binding at 37 degrees C was rapidly reversible and completely blocked by a monoclonal antibody, LJ-Ib10, previously shown to be directed against the alpha-thrombin interaction site on glycoprotein (GP) Ib alpha. By 2-5 min, however, binding was no longer fully reversible and was only partially inhibited by the anti-GP Ib alpha antibody. Results were similar at room temperature (22-25 degrees C), whereas the initial characteristics of alpha-thrombin interaction with platelets were preserved for at least 20 min at 4 degrees C. Equilibrium binding isotherms obtained at the latter temperature were compatible with a two-site model, but the component ascribed to GP Ib alpha, completely inhibited by LJ-Ib10, had "moderate" affinity (kd on the order of 10(-8) M) and relatively high capacity, rather than "high" affinity (kd on the order of 10(-10) M) and low capacity as currently thought. The parameters of alpha-thrombin binding to intact GP Ib alpha on platelets at 4 degrees C corresponded closely to those measured with isolated GP Ib alpha fragments regardless of temperature. Blocking the alpha-thrombin-GP Ib alpha interaction caused partial inhibition of ATP release and prevented the association with platelets of measurable proteolytic activity. These results support the concept that GP Ib alpha contributes to the thrombogenic potential of alpha-thrombin.