Merkel cell carcinoma in elderly: case report and review of the literature.

Merkel cell carcinoma (MCC) is a rare neuroendocrine tumour of the skin, characterised by an aggressive clinical course. The incidence of this rare neoplasia is rapidly increasing. Herein we report our experience with a patient who developed a MCC of the inguinal region.

Integrative molecular analysis of combined small-cell lung carcinomas identifies major subtypes with different therapeutic opportunities.

BACKGROUND: Combined small-cell lung cancer (C-SCLC) is composed of SCLC admixed with a non-small-cell cancer component. They currently receive the same treatment as SCLC. The recent evidence that SCLC may belong to either of two lineages, neuroendocrine (NE) or non-NE, with different vulnerability to specific cell death pathways such as ferroptosis, opens new therapeutic opportunities also for C-SCLC. MATERIALS AND METHODS: Thirteen C-SCLCs, including five with adenocarcinoma (CoADC), five with large-cell neuroendocrine carcinoma (CoLCNEC) and three with squamous cell carcinoma (CoSQC) components, were assessed for alterations in 409 genes and transcriptomic profiling of 20 815 genes. RESULTS: All 13 cases harbored TP53 (12 cases) and/or RB1 (7 cases) inactivation, which was accompanied by mutated KRAS in 4 and PTEN in 3 cases. Potentially targetable alterations included two KRAS G12C, two PIK3CA and one EGFR mutations. Comparison of C-SCLC transcriptomes with those of 57 pure histology lung cancers (17 ADCs, 20 SQCs, 11 LCNECs, 9 SCLCs) showed that CoLCNEC and CoADC constituted a standalone group of NE tumors, while CoSQC transcriptional setup was overlapping that of pure SQC. Using transcriptional signatures of NE versus non-NE SCLC as classifier, CoLCNEC was clearly NE while CoSQC was strongly non-NE and CoADC exhibited a heterogeneous phenotype. Similarly, using ferroptosis sensitivity/resistance markers, CoSQC was classified as sensitive (as expected for non-NE), CoLCNEC as resistant (as expected for NE) and CoADC showed a heterogeneous pattern. CONCLUSIONS: These data support routine molecular profiling of C-SCLC to search for targetable driver alterations and to precisely classify them according to therapeutically relevant subgroups (e.g. NE versus non-NE).

Long-term outcome following Helicobacter pylori eradication in a retrospective study of 105 patients with localized gastric marginal zone B-cell lymphoma of MALT type.

BACKGROUND: Treatment aimed at eradicating Helicobacter pylori infection results in lymphoma remission in most localized gastric mucosa-associated lymphoid tissue (MALT) lymphomas. The aim of this survey is to investigate the long-term effect of this therapeutic approach in a large series of patients. METHODS: One hundred and five patients with localized gastric MALT lymphoma were initially treated only with H. pylori eradication regimens. Lymphoma responses were graded using the Wotherspoon score. RESULTS: Helicobacter pylori, detected by histology in 81% of cases, was eradicated in all positive patients. Histological regression of the lymphoma was achieved in 78 of 102 assessable patients [76%, 95% confidence interval (CI): 67% to 84%] with complete remission (score 0-2) in 66 and partial remission (score 3) in 12. At a median follow-up time of 6.3 years, histological remission was consistently confirmed in 33 of 74 assessable patients, while 25 had score fluctuations (from 0 to 4) and 13 presented a lymphoma relapse (score 5). Only one patient had a distant progression. Transformation to a large-cell lymphoma was seen in two cases. The 5- and 10-year overall survival is 92% (95% CI: 84% to 96%) and 83% (95% CI: 70% to 91%), respectively. Only one patient died of lymphoma after transformation to a high-grade lymphoma. CONCLUSIONS: Helicobacter pylori eradication resulted in complete lymphoma remission in the majority of cases. Long-term clinical disease control was achieved in most patients. A watch and wait policy appears to be safe in patients with minimal residual disease or histological-only local relapse.

Early involvement of 6q in surface epithelial ovarian tumors.

Complex karyotypes are often seen in primary surface epithelial ovarian tumors (SEOTs). Conventional cytogenetic as well as fluorescence in situ hybridization analyses coupled with loss of heterozygosity studies identified abnormalities of chromosome 6 as one of the most frequent lesions in these types of tumors. We performed cytogenetic analysis of direct preparations from 40 SEOTs, including borderline tumors and low-, intermediate-, and high-grade carcinomas to verify the frequency of chromosome 6 alterations. We also carried out fluorescence in situ hybridization analysis with a chromosome 6 library and yeast artificial chromosome clones from a region of the same chromosome (6q27). Chromosome 6 abnormalities were identified in 30 of 32 analyzable SEOTs. Twenty-five of 32 cases showed a deletion of 6q irrespective of their histological grade. We wish to underline that this is the first report proving that del(6q) was the most frequent chromosome anomaly in near-diploid SEOTs and that it was the sole anomaly observed in four SEOTs with diploid complement. Our findings suggest that abnormalities of the telomeric region of chromosome 6 (6q27) may be considered one of the earliest lesions in the pathogenesis of ovarian carcinomas.

Gastric GISTs: Analysis of c-Kit, PDGFRA and BRAF mutations in relation to prognosis and clinical pathological characteristics of patients - A GIRCG study.

BACKGROUND: Gastric gastrointestinal stromal tumors (GISTs) represent a subgroup of GISTs with a better prognosis than those located in other areas. In this retrospective study we performed a molecular characterization of a large series of patients with gastric GISTs in relation to clinical-pathological characteristics and prognosis. METHODS: DNA was extracted from paraffin-embedded sections from 221 gastric GIST patients submitted to surgery. Exons 9, 11, 13 and 17 of KIT, exons 12 and 18 of PDGFRA and exons 11 and 15 of BRAF were analyzed by direct sequencing. Cox regression analysis adjusted for clinical-pathological factors was performed to evaluate KIT and PDGFRA mutations in relation to the composite endpoint of relapse or death. RESULTS: KIT and PDGFRA mutations were observed in 119 (53.8%) and 56 (25.3%) patients, respectively, whereas 46 (20.8%) patients had wild type (wt) disease. Univariable analyses showed that a high Miettinen risk category and the presence of ulceration and KIT deletions were associated with increased risk of relapse or death (p < 0.001; p = 0.0389 and p = 0.002, respectively). After adjusting for Miettinen risk score, KIT deletions remained an independent prognostic factor (HRadj = 2.65, 95% CI [1.15-6.13], p = 0.023). Moreover, KIT deletions in exon 11 codons 557, 558 or 559 were associated with a higher risk of relapse or death than wt tumors (HRadj = 3.29 95% CI [1.64-6.64], p = 0.001). CONCLUSIONS: KIT deletions in exon 11, especially those involving codons 557, 558 or 559, were correlated with a more aggressive gastric GIST phenotype and increased risk of relapse or death.

A large 6q deletion is a common cytogenetic alteration in fibroadenomas, pre-malignant lesions, and carcinomas of the breast.

To assess whether early breast lesions are the precursors of invasive carcinomas, three classes of breast lesions, namely benign tumors (including fibroadenomas), putative premalignant lesions (including cases of atypical hyperplasia), and invasive carcinomas, were compared at the cytogenetic and molecular cytogenetic levels. Genetic relatedness was clearly demonstrated by the sharing of several anomalies, among which 6q deletions outnumbered all of the other alterations detected. Indeed, deletions of the long arm of chromosome 6, most likely occurring in epithelial cells, were present in 83.9% of benign breast tumors, 64% of putative premalignant lesions, and 77.4% of analyzable carcinomas. Furthermore, the interval between 6q24 and qter appeared to be the common region of deletion in all three classes of breast lesions, whereas the minimal common region of deletion was 6q27-qter. Interestingly, the latter region was reported previously to be deleted in benign ovarian tumors and recently found to harbor a gene (SEN6) that is important for SV40-mediated immortalization of human cells.

Chromosome 6 abnormalities in ovarian surface epithelial tumors of borderline malignancy suggest a genetic continuum in the progression model of ovarian neoplasms.

PURPOSE: We used conventional cytogenetics, molecular cytogenetics, and molecular genetic analyses to study the pattern of allelic loss on chromosome 6q in a cohort of borderline epithelial ovarian tumors. EXPERIMENTAL DESIGN: Fifteen tumor samples were collected from patients undergoing surgery for ovarian tumors. The tumors of borderline malignancy, classified according to the standard criteria, included 4 mucinous and 11 serous tumors. Cytogenetic and molecular cytogenetic (with yeast artificial chromosome clones from 6q26-27) studies were performed on tumor areas contiguous to those used for histological examination ensuring the appropriate sampling. Moreover loss of heterozygosity analysis was performed using PCR amplification of eight microsatellite markers mapping on 6q27 (D6S193, D6S297), 6q26 (D6S305, D6S415, D6S441), 6q21 (D6S287), 6q16 (D6S311), and 6q14 (D6S300). RESULTS: Deletions of this chromosome arm, in particular of 6q24-27, were the most frequent lesions found in this set of tumors. In a tumor with a normal karyotype the only detectable alteration was a deletion of approximately 300 kb within the D6S149-D6S193 interval at band 6q27. This is, to date, the smallest deletion described for borderline tumors. CONCLUSION: Alterations in the above-mentioned interval are a common finding in advanced ovarian carcinomas but also in benign ovarian cysts, implying that some tumors of borderline malignancy may arise from benign tumors and that malignant ones may evolve from tumors of borderline malignancy. Genes located in 6q27 seem to be crucial for this mechanism of early events in ovarian tumorigenesis.

Cell biology, clinicopathological profile, and classification of gastro-enteropancreatic endocrine tumors.

Recent developments in the field of endocrine cell biology and pathology at both morphological and molecular levels are briefly outlined and discussed as a basis for endocrine tumor characterization. The main tools available for identifying the endocrine nature of the tumors, their pathogenetic interpretation. and experimental reproduction with special emphasis on tumor antecedents are reported. Based on this, classifications of endocrine tumors of the pancreas and gastrointestinal tract are developed, covering most clinical (hyperfunctional syndromes included), pathological, and biological patterns, with special emphasis on tumor prognosis.

Primary oat cell carcinoma of the kidney.

A malignant renal neoplasm with all the morphologic attributes of oat cell (small cell, neuroendocrine) carcinoma is presented. It metastasized widely to regional lymph nodes and resulted in the death of the patient. Ultrastructurally, the tumor contained dense-core endocrine-type secretory granules. It had a cell component which was argyrophilic and which gave a positive immunocytochemical reaction for calcitonin. To the best of our knowledge, this is the first documentation of this tumor type in the kidney.

Neuroendocrine carcinoma within lymph nodes in the absence of a primary tumor, with special reference to Merkel cell carcinoma.

We report eight cases of neuroendocrine carcinomas found within inguinal (five cases), axillary (two cases), and submandibular (one case) lymph nodes. The patients underwent extensive investigations, but no primary tumor was found in any case. Although the existence of an occult or regressed primary cannot be ruled out, the possibility of a lymph node origin should be considered on the basis of epithelial inclusions or anomalous carcinomatous differentiation of stem cells of the lymphoreticular system.

Gastric argyrophil carcinoidosis in patients with Zollinger-Ellison syndrome due to type 1 multiple endocrine neoplasia. A newly recognized association.

We report four cases of gastric argyrophil carcinoidosis arising in the oxyntic mucosa of patients with Zollinger-Ellison syndrome as part of type 1 multiple endocrine neoplasia (MEN) syndrome. Multiple mucosal and submucosal carcinoids were seen in combination with innumerable hyperplastic and dysplastic growths of argyrophil endocrine cells disseminated in the entire acidopeptic mucosa. Histochemical and ultrastructural investigation indicated that the argyrophil enterochromaffin-like (ECL) cell, a type of endocrine cell normally restricted to the oxyntic mucosa and very sensitive to gastrin stimulation, was a major component of the carcinoidosis. Five similar cases were found in the literature. Because argyrophil ECL cell carcinoid or carcinoidosis is unusual in patients who have the Zollinger-Ellison syndrome but do not have MEN, we believe that the genetic trait of the MEN syndrome has an important permissive role in the promotion of gastric carcinoids through the hypergastrinemia inherent to Zollinger-Ellison syndrome.

Hyperplastic, dysplastic, and neoplastic enterochromaffin-like-cell proliferations of the gastric mucosa. Classification and histogenesis.

Endocrine cells of the gastric oxyntic mucosa, and especially the enterochromaffin-like (ECL) cells, are the progenitors of gastrin-promoted proliferative lesions whose tumorigenic potential largely depends on the background condition in which they arise. Hypertrophic gastropathy due to the familial multiple endocrine neoplasia (MEN-1)-associated or sporadic Zollinger-Ellison syndrome (ZES), diffuse chronic atrophic gastritis restricted to the corpus-fundus (type A CAG), with or without associated pernicious anemia, and Helicobacter pylori-related multifocal chronic atrophic gastritis are the usual background for such growths. The endocrine cell lesions have been classified as pseudohyperplasia (cell clustering unassociated with cell proliferation), hyperplasia (diffuse, linear, micronodular, adenomatoid), dysplasia (enlarged, adenomatous or fused micronodules, microinfiltration, nodular growth), and neoplasia (intramucosal or invasive carcinoids). The entire spectrum of endocrine cell proliferation, from hyperplasia to dysplasia and neoplasia, has been observed in MEN-ZES and diffuse type A CAG. Both hyperplastic and pseudohyperplastic changes occur with some frequency in the H. pylori-related chronic gastritis associated with ulcer disease or dyspepsia. However, because no progression to dysplastic or neoplastic lesions has thus far been documented in these latter conditions, their role in gastric endocrine cell tumorigenesis appears negligible.

Oncocytic meningioma.

Six cases of meningioma showing oncocytic changes are described. The lesions were composed mostly of sheets, nests, and cords of large polygonal cells with finely granular eosinophilic cytoplasm rich in mitochondria. Neoplastic cells showed nuclear pleomorphism with prominent nucleoli. Necrosis and high mitotic rate were present in the majority of cases. Oncocytic differentiation was demonstrated by conventional histology, immunocytochemistry, electron microscopy, and Western-blot analysis. Oncocytic meningiomas showed an aggressive behavior; recurrences were observed in three cases, and invasion of brain cortex was evident in other two cases.

Intestinal and diffuse gastric cancers arise in a different background of Helicobacter pylori gastritis through different gene involvement.

Investigation of extensively sampled nontumor gastric mucosa from 205 early gastric cancers showed Helicobacter pylori colonization in 85% of cases, including 100% of diffuse and 78% (83% in 97 cases with Swiss rolls) of glandular or mixed cancers. Intestinal metaplasia, including its type III variant, was prominent in the mucosa associated with glandular and mixed (but not diffuse) early cancers. Both glandular (usually called "intestinal") and diffuse-type cancers showed admixtures of intestinal and gastric tumor cell phenotypes. Both p53 gene mutations and p53 protein immunostaining were essentially restricted to glandular or mixed cancers and associated dysplastic lesions. Their appearance in the advanced stage of diffuse cancer was partly due to a change of the histologic pattern from glandular to diffuse during progression of some tumors. Loss of laminin, beta I integrin, or zonula adherens junctions was a common finding in both early and advanced diffuse cancer. It is concluded that two main pathways operate in gastric carcinogenesis, both starting from H. pylori gastritis and both leading to phenotypically variable, often mixed gastric/intestinal tumor growth. However, only one of the two pathways involves intestinal metaplasia, its type III variant, p53 gene alteration, and dysplasia to end in glandular cancer. In the other pathway, diffuse cancer apparently arises directly from hyperplastic, sometimes atypical necks of mostly nonmetaplastic gastric glands, through primary involvement of genes affecting cell-cell and cell-matrix junctional proteins.

Mucinous cystic tumors of the pancreas: clinicopathological features, prognosis, and relationship to other mucinous cystic tumors.

The clinicopathological features of 56 patients with mucinous cystic tumors (MCTs) of the pancreas were studied. Particular attention was paid to the prognosis of MCTs and the relationship to their ovarian, hepatic, and retroperitoneal counterparts. To distinguish MCTs from pancreatic intraductal papillary-mucinous tumors, MCTs were defined as tumors lacking communication with the duct system and containing mucin-producing epithelium, usually supported by ovarian-like stroma. All 56 tumors occurred in women (mean age 48.2 years) and were preferentially (93%) located in the body and tail of the pancreas. In accordance with the WHO classification, MCTs were divided into adenomas (n = 22), borderline tumors (n= 12), and noninvasive and invasive carcinomas (n = 22). Survival analysis revealed the extent of invasion to be the most significant prognostic factor (p<0.0001). Malignancy correlated with multilocularity and presence of papillary projections or mural nodules, loss of ovarian-like stroma, and p53 immunoreactivity. Stromal luteinization with expression of tyrosine hydroxylase, calretinin, or alpha inhibin was found in 66% of the cases. We conclude that the biologic behavior of MCTs is predictable on the basis of the extent of invasion. The similarities (i.e. gender, morphology, stromal luteinization) between pancreatic MCT and its ovarian, hepatobiliary, and retroperitoneal counterparts suggest a common pathway for their development.

The pathology of the gastrointestinal endocrine system.

Among endocrine tumors occurring in the gastrointestinal tract, midgut argentaffin EC cell carcinoids, gastric argyrophil ECL cell carcinoids, duodenal gastrin cell tumors, and rectal trabecular L cell carcinoids (in order of decreasing frequency) are those occurring more frequently. Together, they account for more than 80% of such tumors. Duodenal somatostatin cell tumors, gangliocytic paragangliomas, and differentiated neuroendocrine carcinomas are also well-defined tumor entities. The carcinoid syndrome, either classical, with intermittent flushing, hypotension, and diarrhea, or atypical, with persistent histamine-type red flushing, bronchospasm, and no diarrhea, and Zollinger-Ellison syndrome, with severe peptide ulcer disease, are the only hyperfunctional syndromes consistently found in association with these tumors. The carcinoid syndrome occurs in about 10% of gastrointestinal carcinoids, usually in their advanced, metastatic stage. The Zollinger-Ellison syndrome occurs in association with about 40% of intestinal gastrin cell tumors, including small intramural growths. Tumor prognosis depends on the mode and site of presentation, histology, cell type(s), size, level of invasion, metastases (especially distant metastases), and associated clinical syndrome or background disease. Hormones, trophic factors, inherited genetic traits, somatic mutations, and some chronic inflammatory processes are pathogenetically important in a large proportion of cases.

The foveolar cell component of gastric cancer.

M1, a mucin antigen, and cathepsin E, an aspartic proteinase, are both expressed in normal gastric superficial-foveolar epithelial cells. In this study, we determined by immunohistochemical staining the prevalence of these antigens in 316 gastric cancers representative of the main histologic types and stages of the disease. M1 was expressed in 201 cases (64%) and cathepsin E was expressed in 235 cases (75%) of the 313 cases investigated. Both antigens were expressed more commonly in diffuse and mixed cancers than in glandular tumors. M1 was found in 64 of 83 (77%) diffuse cancers and in 48 of 59 (81%) mixed cancers, but in only 74 of 146 (51%) glandular cancers. For cathepsin E, the prevalence was 93% in diffuse cancer, 81% in mixed cancer, and 71% in the 143 glandular cancers examined. Among 25 mucoid tumors, 15 (60%) expressed M1 but only eight (32%) expressed cathepsin E. Overall, 262 (84%) of the tumors expressed at least one of these antigens and of these, 173 (66%) expressed both antigens. No significant difference in the prevalence of M1 or cathepsin E was found between early and advanced cancer or between metastatic and nonmetastatic cancer. The two markers differed in their intracellular localization. In superficial-foveolar cells, M1 immunostaining was concentrated in secretory granules, Golgi complex, and luminal mucous, whereas cathepsin E was found in the endoplasmic reticulum. Moreover, cathepsin E, but not M1, was found in the enterocytes of duodenal villi and, occasionally, in mucopeptic cells. Parallel histochemical and ultrastructural investigations confirmed the occurrence in gastric cancer of foveolar-type cells, manifested by periodic acid-Schiff- and/or alcian blue-reactive mucous granules having a punctate substructure. We conclude that superficial-foveolar cell differentiation is common in gastric cancer and is a major component of this type of tumor. However, pure foveolar cell differentiation is rare. Rather, most gastric cancers consist of cells exhibiting features of foveolar, intestinal, and mucopeptic cell lines.

Ovarian metastases from colorectal carcinoma. Clinicopathologic profile, immunophenotype, and karyotype analysis.

Ovarian metastases from colorectal carcinoma frequently mimic primary ovarian carcinomas. The present study was performed to identify possible criteria helpful in differential diagnosis. Twenty-three ovarian metastases from colorectal carcinomas and 23 primary ovarian carcinomas were evaluated clinicopathologically and immunostained with antigastric M1 antigen, cathepsin E, CA125, vimentin, estrogen and progesterone receptors, cytokeratins 7 and 20, and alpha-inhibin antibodies. We performed a conventional and molecular cytogenetic study on 5 ovarian metastases from colorectal carcinoma using direct preparation, Q banding techniques, and fluorescence in situ hybridization. Integration of clinicopathologic, immunohistochemical, and cytogenetic features is helpful for the differential diagnosis of metastases of colorectal carcinomas from primary ovarian carcinomas. Bilaterality, extrapelvic spreading, high mitotic index, and cytokeratin 20 immunoreactivity, and lack of M1, CA125, and cytokeratin 7 immunoreactivity favor the diagnosis of ovarian metastases from colon carcinomas. The identification of 13q gain as a peculiar, sensitive, and specific marker of colorectal carcinomas seems relevant.

Merkel cell differentiation in trichoblastoma.

Four cases of trichoblastoma rich in Merkel cells (MCs) are reported. They occurred in two men and two women, with ages ranging from 58 to 76 years (mean 67.5 years). MCs were detected immunohistochemically with antibodies to keratin 20, chromogranin A and neuron-specific enolase (NSE). In an attempt at better definition of the nature and role of MCs in trichoblastoma, the distribution of MCs in normal adult and fetal skins obtained at autopsy was studied. In addition, ten cases of sebaceous naevus of Jadassohn (NSJ) were evaluated along similar lines. MCs made up 2-20% of the tumour cells in trichoblastomas; they were present in normal fetal skin and were rare in normal adult skin. All but one of the cases of NSJ showed numerous positive cells in the epidermal component of the lesion with all three antibodies. Six basal cell carcinomas and one syringocystadenoma papilliferum associated with NSJ were negative with keratin 20, chromogranin A and NSE antibodies, whereas a minute trichoblastoma arising against the same background was positive for these markers. Hair follicle cell tumours may recapitulate the skin embryogenesis, as numerous MCs are present in fetal follicles, but only occasional such cells are seen in adult skin.

Revised classification of neuroendocrine tumours of the lung, pancreas and gut.

In this article new classifications of the neuroendocrine tumours of the lung, pancreas and gut are proposed. These classifications use a common frame work and attempt to consider the morphological, functional as well as biological features of the tumours.