Bone marrow megakaryocytic activation predicts fibrotic evolution of Philadelphia-negative myeloproliferative neoplasms.

Philadelphia-negative chronic myeloproliferative neoplasms (MPN) have been traditionally considered as indistinctly slowly progressing conditions; recent evidence proves that a subset of cases have a rapid evolution, so that MPN prognosis needs to be personalized. We identified a new morphological parameter, defined as megakaryocytic activation (M-ACT) based on the coexistence of megakaryocytic emperipolesis, megakaryocytes (MK) cluster formation and evidence of arrangement of collagen fibers around the perimeter of MK. We retrospectively analyzed the bone marrow biopsy of two MPN cohorts of patients with polycythemia (PV) (n=64) and non-PV patients (including essential thrombocythemia, and early/prefibrotic primary myelofibrosis [PMF]) (n=222). M-ACT showed a significant correlation with splenomegaly, white blood cell count, and lactate dehydrogenase serum levels in both groups, with JAK2 V617F allele burden in PV patients, and with CALR mutations, and platelet count in non-PV patients. Progression-free survival, defined as PV-to-secondary MF progression and non-PV-to-overt PMF, was worse in both PV and early/prefibrotic PMF patients with M-ACT in comparison to those without M-ACT (P<0.0001). Interestingly, M-ACT was not found in the subgroup of essential thrombocythemia patients. In conclusion, M-ACT can be helpful in the differential diagnosis of MPN and can represent a new morphologic parameter with a predictive value for progression of MPN.

Soft tissue myxofibrosarcoma: A clinico-pathological analysis of a series of 75 patients with emphasis on the epithelioid variant.

BACKGROUND AND OBJECTIVES: The clinical course of soft tissue myxofibrosarcoma is characterized by a high incidence of recurrences and there is no agreement on how to identify patients at major risk. An epithelioid histological variant has been described, with a possible worse prognosis. We reviewed our series to identify prognostic factors and assess clinical significance of the epithelioid variant. METHODS: We examined the clinico-pathological features of a series of 75 patients affected by soft tissue myxofibrosarcoma at a mean follow-up of 63 months (range 17-132). RESULTS: Disease specific survival and local recurrence free survival were, respectively, 84.8% and 76.8% at 5 years. Seven patients (8.6%) presented with the epithelioid variant with a survival of 62.5%. High grade and epithelioid morphology were negative prognostic factors for patient survival, high grade, and inadequate surgical margins for local recurrence. Radiotherapy had a local protective effect in high grade tumors. CONCLUSIONS: Our experience confirms the difficulties in obtaining wide margins in myxofibrosarcoma and the high rate of recurrence. Local recurrences did not significantly affect survival and a limb-sparing approach can be chosen also in recurrences. Patients affected by the epithelioid variant showed a worse prognosis. Chemotherapy should be considered as adjuvant treatment in this subtype. J. Surg. Oncol. 2016;114:50-55. © 2016 Wiley Periodicals, Inc.

Cartilage differentiation in ependymoma: histogenetic considerations on a new case.

The presence of cartilage in gliomas is a very unusual finding and has been mainly reported in ependymomas and in astrocytomas. A derivation of cartilage from neuroepithelial cells through a neuroepithelial-mesenchymal transition or directly from blood vessel-associated multipotent stromal elements has been proposed. We herein describe a further case of ependymoma with the presence of cartilage in a child affected by a tumor in the posterior fossa. In this case, only the last recurrence, characterized by focal areas of anaplasia, contained a nodule of cartilage. The immunohistochemical expression of fibronectin, tenascin-C, and CD44 was investigated, and the possible role of these molecules in the process of cartilage formation is discussed. Moreover, the literature on the subject is reviewed.

Porocarcinoma of the left arm: A report of a rare skin cancer case and literature review.

Porocarcinoma is a rare type of skin cancer that develops from the intraepidermal ductal part of eccrine sweat glands. It can arise de novo or from poroma ground with high potential for locoregional metastatic spread, morbidity, and mortality. It mostly occurs in elderly patients.

Recurrent BRAF Gene Rearrangements in Myxoinflammatory Fibroblastic Sarcomas, but Not Hemosiderotic Fibrolipomatous Tumors.

Myxoinflammatory fibroblastic sarcoma (MIFS) is a low grade soft tissue sarcoma with a predilection for acral sites, being associated with a high rate of local recurrence but very infrequent distant metastases. Although a t(1;10) translocation resulting in TGFBR3-MGEA5 fusion has been reported as a recurrent genetic event in MIFS, this abnormality is seen only in a subset of cases. As no studies to date have investigated the spectrum of alternative genetic alterations in TGFBR3-MGEA5 fusion negative MIFS, we undertook a genetic analysis of this particular cohort for further molecular classification. Triggered by an index case occurring in the finger of a 37-year-old female and harboring a novel TOM1L2-BRAF fusion by targeted RNA sequencing we investigated potential recurrent BRAF abnormalities by screening a large group of 19 TGFBR3-MGEA5 fusion negative MIFS by fluorescence in situ hybridization. There were 6 (32%) additional MIFS with BRAF genetic abnormalities, including 5 gene rearrangements and one showing BRAF amplification. Interestingly, VGLL3 amplification, a recurrent genetic abnormality coexisting with t(1;10) in some MIFS, was also detected by fluorescence in situ hybridization in 4/6 (67%) BRAF-rearranged MIFS, but not in the BRAF-amplified case. Up-regulated VGLL3 mRNA expression was also demonstrated in the index case by RNA sequencing. The 7 BRAF-rearranged/amplified MIFS arose in the fingers (n=3), and 1 each in wrist, forearm, foot, and knee, of adult patients (36 to 74 y; M:F=4:3). The histologic spectrum ranged from predominantly solid growth of plump histiocytoid to epithelioid tumor cells with focal myxoid change to a predominantly myxoid background with scattered tumor cells. Varying degree of inflammatory infiltrates and large tumor cells with virocyte-like macronucleoli were observed in most cases. Immunohistochemical stains of phosphorylated ERK, a downstream effector of BRAF activation, were positive in all 4 cases tested (2 diffuse strong, 2 focal strong). Unlike t(1;10), BRAF rearrangements were only found in MIFS but not in 6 hemosiderotic fibrolipomatous tumor (HFLT) lacking TGFBR3-MGEA5 fusions (including 2 pure HFLT, 2 hybrid HFLT-MIFS, and 2 associated with pleomorphic hyalinizing angiectatic tumors).

Intestinal metaplasia of the sinonasal mucosa adjacent to intestinal-type adenocarcinoma. A morphologic, immunohistochemical, and molecular study.

It has been hypothesized that the development of sinonasal intestinal-type adenocarcinoma (ITAC) occurs through intestinal metaplasia (IM) of the respiratory and/or glandular epithelium. The aim of this study was to characterize the histological, immunohistochemical, and molecular features of sinonasal IM. Histologic slides from 29 consecutive surgical specimens of ITAC were retrieved. Sections were stained for CDX2, cytokeratin 20 (CK20), MUC2, and p53. The status of TP53 gene exons 4-9 was assessed separately in areas of IM and in ITAC. Foci of IM were detected in eight cases (27.5%). They were all positive for CK20 and CDX2, while MUC2 was detected in six cases (75%). In six cases (75%), the metaplastic foci showed signs of dysplasia, including nuclear enlargement with increased nucleus to cytoplasm ratio, nuclear hyperchromasia, loss of nuclear polarity, and presence of prominent nucleoli. P53 nuclear immunoreactivity was observed in four cases. TP53 gene sequencing was successfully performed in six cases and revealed the same mutation in both IM and ITAC in two cases (c.832C > T and c.215G > C), while another ITAC showed a mutation that was not present in the adjacent IM (c.536A > G). In conclusion, our study suggests a possible clonal relationship between areas of sinonasal IM and ITAC, indicating that IM may represent a precursor lesion of ITAC. Improving the knowledge on the morphological and molecular features of IM is a key step to identify reliable biomarkers to determine the risk of sinonasal ITAC development.

Ectopic salivary gland tissue in a Rathke's cleft cyst.

The presence of salivary gland tissue in the sella turcica has rarely been reported, mainly after pituitary examination at autopsy. Only five symptomatic cases have previously been described, mainly associated with Rathke's cleft cyst. We report a 17-year-old boy presenting with headaches and hyperprolactinemia. The MRI showed a 19 mm sellar mass that at surgery revealed as a cystic lesion filled with mucinous fluid. The histological examination documented the presence of ectopic salivary gland tissue in the wall of a Rathke's cleft cyst. The present report focuses on the possible pitfalls when dealing with unusual sellar lesions, and the need of increased awareness of this rare condition.