José A. Jiménez-Heffernan

Immunohistochemical characterization of fibroblast subpopulations in normal peritoneal tissue and in peritoneal dialysis-induced fibrosis

Peritoneal fibrosis is one of the most common morphological changes observed in continuous ambulatory peritoneal dialysis (CAPD) patients. Both resident fibroblasts and new fibroblast-like cells derived from the mesothelium by epithelial-to-mesenchymal transition are the main cells involved fibrogenesis. In order to establish markers of peritoneal impairment and pathogenic clues to explain the fibrogenic process, we conducted an immunohistochemical study focused on peritoneal fibroblasts. Parietal peritoneal biopsies were collected from four patient groups: normal controls (n=15), non-CAPD uremic patients (n=17), uremic patients on CAPD (n=27) and non-renal patients with inguinal hernia (n=12). To study myofibroblastic conversion of mesothelial cells, α-smooth muscle actin (SMA), desmin, cytokeratins and E-cadherin were analyzed. The expression of CD34 by fibroblasts was also analyzed. Fibroblasts from controls and non-CAPD uremic patients showed expression of CD34, but no myofibroblastic or mesothelial markers. The opposite pattern was present during CAPD-related fibrosis. Expression of cytokeratins and E-cadherin by fibroblast-like cells and α-SMA by mesothelial and stromal cells supports that mesothelial-to-myofibroblast transition occurs during CAPD. Loss of CD34 expression correlated with the degree of peritoneal fibrosis. The immunophenotype of fibroblasts varies during the progression of fibrosis. Myofibroblasts seem to derive from both activation of resident fibroblasts and local conversion of mesothelial cells.

Epithelial-to-mesenchymal transition of mesothelial cells is an early event during peritoneal dialysis and is associated with high peritoneal transport.

Ultrafiltration (UF) failure is a consequence of long-term peritoneal dialysis (PD). Fibrosis, angiogenesis, and vasculopathy are causes of this functional disorder after 3-8 years on PD. Epithelial-to-mesenchymal transition (EMT) of mesothelial cell (MC) is a key process leading to peritoneal fibrosis with functional deterioration. Our purpose was to study the peritoneal anatomical changes during the first months on PD, and to correlate them with peritoneal functional parameters. We studied 35 stable PD patients for up to 2 years on PD, with a mean age of 45.3+/-14.5 years. Seventy-four percent of patients presented loss of the mesothelial layer, 46% fibrosis (>150 microm) and 17% in situ evidence of EMT (submesothelial cytokeratin staining), which increased over time. All patients with EMT showed myofibroblasts, while only 36% of patients without EMT had myofibroblasts. The number of peritoneal vessels did not vary when we compared different times on PD. Vasculopathy was present in 17% of the samples. Functional studies were used to define the peritoneal transport status. Patients in the highest quartile of mass transfer area coefficient of creatinine (Cr-MTAC) (>11.8 ml min(-1)) showed significantly higher EMT prevalence (P=0.016) but similar number of peritoneal vessels. In the multivariate analysis, the highest quartile of Cr-MTAC remained as an independent factor predicting the presence of EMT (odds ratio 12.4; confidence interval: 1.6-92; P=0.013) after adjusting for fibrosis (P=0.018). We concluded that, during the first 2 PD years, EMT of MCs is a frequent morphological change in the peritoneal membrane. High solute transport status is associated with its presence but not with increased number of peritoneal vessels.

Adrenal Gland Leiomyoma in a Child with Acquired Immunodeficiency Syndrome

An adrenal gland leiomyoma was incidentally found at autopsy in a 2-year-old boy with acquired immunodeficiency syndrome (AIDS). Smooth muscle neoplasms have been described in pediatric AIDS and affect mainly the tracheobronchopulmonary, gastrointestinal, and hepatobiliary systems. An association between Epstein-Barr virus (EBV) and smooth muscle tumors in patients with AIDS has been described. This case is the first leiomyoma to be reported in the adrenal gland of a child with AIDS. EBV genome was demonstrated in the tumor by polymerase chain reaction.

Carcinoma‐associated fibroblasts derive from mesothelial cells via mesothelial‐to‐mesenchymal transition in peritoneal metastasis

Peritoneal dissemination is a frequent metastatic route for cancers of the ovary and gastrointestinal tract. Tumour cells metastasize by attaching to and invading through the mesothelial cell (MC) monolayer that lines the peritoneal cavity. Metastases are influenced by carcinoma‐associated fibroblasts (CAFs), a cell population that derives from different sources. Hence, we investigated whether MCs, through mesothelial–mesenchymal transition (MMT), were a source of CAFs during peritoneal carcinomatosis and whether MMT affected the adhesion and invasion of tumour cells. Biopsies from patients with peritoneal dissemination revealed the presence of myofibroblasts expressing mesothelial markers in the proximity of carcinoma implants. Prominent new vessel formation was observed in the peritoneal areas harbouring tumour cells when compared with tumour‐free regions. The use of a mouse model of peritoneal dissemination confirmed the myofibroblast conversion of MCs and the increase in angiogenesis at places of tumour implants. Treatment of omentum MCs with conditioned media from carcinoma cell cultures resulted in phenotype changes reminiscent of MMT. Adhesion experiments demonstrated that MMT enhanced the binding of cancer cells to MCs in a β1‐integrin‐dependent manner. Scanning electron microscopy imaging showed that the enhanced adhesion was mostly due to increased cell–cell interaction and not to a mere matrix exposure. Invasion assays suggested a reciprocal stimulation of the invasive capacity of tumour cells and MCs. Our results demonstrate that CAFs can derive from mesothelial cells during peritoneal metastasis. We suggest that MMT renders the peritoneum more receptive for tumour cell attachment/invasion and contributes to secondary tumour growth by promoting its vascularization. Copyright

Fine needle aspiration cytology of endocrine neoplasms of the pancreas. Morphologic and immunocytochemical findings in 20 cases.

OBJECTIVEnTo analyze the role of fine needle aspiration (FNA) cytology in the preoperative diagnosis of pancreatic endocrine neoplasms.nnnMETHODSnCytologic and histologic diagnoses of pancreatic endocrine tumors were reviewed. A total of 20 FNA cytologic procedures from 20 patients were selected. A false positive case, a retroperitoneal paraganglioma, was also reviewed. Two groups of patients were established: (1) those in whom a surgical biopsy with an immunohistochemical study was available (n = 13), and (2) those with a pancreatic tumor in which the diagnosis was confirmed by immunocytochemical studies (n = 7). In 13 cases the pancreatic tumor was aspirated, while in 7, liver metastases were studied. The immunoexpression of chromogranin and synaptophysin was evaluated in alcohol-fixed smears from 12 and 11 cases, respectively.nnnRESULTSnOne false negative and 1 false positive diagnosis were present. In the remaining 19 cases a cytologic diagnosis of pancreatic endocrine tumor was given. Main cytologic features were: (1) a prominent cellular dissociation with many single cells and small, poorly cohesive groups; (2) intermediate to large size cells with ill-defined cytoplasm, naked or eccentric nuclei, and frequent binucleation; and (3) variable nuclear pleomorphism with the characteristic finely granular distribution of the chromatin. Immunocytochemical evidence of endocrine differentiation (chromogranin or synaptophysin) was present in the 12 cases analyzed.nnnCONCLUSIONnFNA cytology offers the possibility of a precise preoperative, noninvasive diagnosis of pancreatic endocrine tumors. Cytologic features differ considerably from those of pancreatic adenocarcinoma, allowing differentiation from nonfunctioning endocrine neoplasms. In difficult cases immunocytologic studies are very helpful.

Role of fine needle aspiration cytology in the diagnosis and management of Warthin’s tumour of the salivary glands

J. M. Viguer, B. Vicandi, J. A. Jiménez‐Heffernan, P. López‐Ferrer, P. González‐Peramato and C. Castillou2028Role of fine needle aspiration cytology in the diagnosis and management of Warthin’s tumour of the salivary glands

Myofibroblastic differentiation in simple peritoneal sclerosis

Objective To analyze the presence of myofibroblasts in a series of peritoneal dialysis (PD) patients with simple sclerosis and non-PD, uremic patients. Since there is a close correlation between active fibrosis and myofibroblastic differentiation we wanted to test if myofibroblasts are present in uremic, non-PD peritoneal samples. To determine if there are correlations between myofibroblastic presence and other functional and morphologic peritoneal parameters. Methods Biopsies were collected from three patient groups: 1) Normal control samples (n=15) of parietal and visceral peritoneum 2) non-PD uremic patients (n=16); and 3) uremic patients on PD (n=32). Peritoneal morphologic and functional parameters and immunohistochemical expression of α-smooth muscle actin was analyzed in each case. Vascular endothelial growth factor (VEGF), bcl-2 anti-apoptotic protein, and progesterone receptor was evaluated in a subset of cases. Results Myofibroblasts were present in 56.3% of the patients with PD-related simple sclerosis. In most cases they were distributed in the upper submesothelial area. None of the biopsies from normal controls and uremic, non-PD patients showed myofibroblasts. Within the group of PD patients, myofibroblasts showed no correlation with time on dialysis, urea/creatinine MTAC, episodes of peritonitis, submesothelial thickening, hyalinizing vasculopathy or mesothelial status. In a subset of PD patients VEGF expression was observed in submesothelial fibroblastic cells. No expression of progesterone receptor or bcl-2 was observed. Conclusions Myofibroblasts are a reliable and simple indicator of fibrosis since they appear in early stages of PD treatment and in patients with minor morphologic anomalies. They are not exclusive of patients with sclerosing peritonitis, ultrafiltration loss or long standing treatment. Their absence in non-PD, uremic patients suggest that uremia-related fibrosis takes place without a significant participation of myofibroblasts.

Fine needle aspiration cytology of mammary carcinoma with osteoclast-like giant cells

Carcinoma with osteoclast‐like giant cells (OCGC) is an uncommon neoplasm characterized by giant cells, prominent vascularization, haemorrhage and areas of cribriform epithelial growth with moderate atypia. Multinucleated giant cells (MGC) have been described in several other breast lesions raising an interesting differential diagnosis, mainly with benign disorders. Due to its rarity few cases have been described cytologically. We retrospectively reviewed 13 fine needle aspiration samples from nine patients with this variant of carcinoma. Nine corresponded to breast tumours and four to axillary, liver, subcutaneous and mediastinal metastatic lesions. The expression of CD68 by giant cells was evaluated immunocytochemically in six cases. All patients had a complete pathological study of the breast neoplasm. Smears showed a double component of epithelial and giant cells. Epithelial clusters were predominantly of intermediate size with irregular contours. Most were cohesive but others showed cellular dissociation with scarce to moderate cellular pleomorphism. Giant cells had well defined, deeply stained cytoplasm and round to elongated morphology. Two metastatic cases were devoid of them. Haemosiderin‐laden macrophages were common in smears from breast tumours. In the six cases tested CD68 was expressed in MGC. Cytological features of mammary carcinoma with OCGC correlate closely with the histological ones. Most cases are clearly recognizable as malignant but in others cytological atypia may be minimal, mimicking a benign lesion. In difficult cases the presence of haemosiderin‐laden macrophages and the histiocytic nature of the MGC are helpful diagnostic features.

Fine needle aspiration cytology of intranodal myofibroblastoma. A case report.

BACKGROUNDnIntranodal myofibroblastoma is a rare, primitive, mesenchymal neoplasm of the lymph nodes first described in 1989. It behaves in a benign fashion and has a great predilection for the inguinal region.nnnCASE REPORTnA 56-year-old man was referred for fine needle aspiration cytology of an inguinal lymph node. Smears were moderately cellular, with a predominant population of single, small spindle cells with no atypia. Most neoplastic cells were distributed as dissociated, single cells, with few groups. The cells showed metachromatic stromal material with a fibrillary quality. Nuclei were elongated, with pointed ends and occasional twisted forms. A remarkable finding on Papanicolaou-stained smears was hemosiderin granules. After a cytologic report of low grade spindle cell tumor, the node was excised, and a histologic and immunohistochemical diagnosis of intranodal myofibroblastoma was established.nnnCONCLUSIONnIntranodal myofibroblastoma should always be considered when aspirating solitary inguinal lymph nodes. The presence of a low grade spindle cell pattern of variably dissociated cells with hemosiderin granules should lead to immunocytochemical studies. Muscle-specific actin expression in the absence of S-100 protein and vascular markers permits a more specific diagnosis.

Fine needle aspiration cytology of Langerhans cell sarcoma

Dear Editor, Langerhans cell (LC) sarcoma is a neoplastic proliferation of LC with evident malignant histological features. It is considered as an aggressive variant of LC histiocytosis and the World Health Organization classification refers to it as a specific entity. Histology reveals an anaplastic neoplasm and immunohistochemical studies are necessary for a precise diagnosis. In some cases, nuclear indentations may suggest the diagnosis. In this report, we describe a patient with LC sarcoma that was initially evaluated by fine needle aspiration cytology (FNAC). The tumour presented as a cervical adenopathy and resulted in a troublesome cytological diagnosis. The rarity of this neoplasm is reflected by the existence of very few previous cytological descriptions. A 67-year-old man was referred to our laboratory for FNAC of a laterocervical mass. Physical examination revealed a cervical 3 · 4 cm, non-mobile, firm mass that was aspirated by a pathologist by using a 23-gauge needle. At the time of aspiration no other lesions were present. Smears were hypercellular and showed a single cell population of large neoplastic cells. Naked nuclei were present but most cells had a small to moderate amount of deeply stained cytoplasm (Figure 1). Nuclei were pleomorphic with irregular contours and indentations (Figure 2). A few cells were binucleated and others had a multilobated nucleus. Mitotic figures were common. In addition to the neoplastic population, small lymphocytes, neutrophils and a few eosinophils were present. The background was granular, with numerous necrotic cells. Lymphoglandular bodies were not a prominent finding. These cytological features raised the possibilities of highgrade, non-Hodgkin’s lymphoma and metastatic carcinoma. Immunocytochemistry revealed an intense expression of CD45 in the neoplastic cells. It was performed on alcohol-fixed material using a streptavidin–biotin method. Cytokeratins AE1/A3 were not expressed. A preoperative cytological diagnosis of malignant, high-grade lymphoproliferative neoplasm was given. Surgical biopsy revealed a diffuse growth of large, anaplastic cells with a moderate amount of cytoplasm and areas of necrosis (Figure 3). Although a Correspondence: J. A. Jiménez-Heffernan, Servicio de Anatomı́a Patológica, Hospital Universitario, Donantes de Sangre s/n, 19002 Guadalajara, Spain. Tel.: +34 949209220; Fax: +34 913572145; E-mail: jjheffernan@yahoo.com Figure 1. Smear showing a single cell pattern of large neoplastic cells with moderate amount of cytoplasm and a few small lymphocytes (Diff-Quik, ·177).