Melanocytic Myxoid Spindle Cell Tumor With ALK Rearrangement (MMySTAR): Report of 4 Cases of a Nevus Variant With Potential Diagnostic Challenge.

Melanocytic tumors rarely display extensive dermal myxoid deposits except in the myxoid variant of melanoma. We describe in 4 patients the unusual association of morphologic and genetic features. All cases occurred in males and were located on the limbs or proximal girdle area. Age at diagnosis ranged from 8 to 47 years. Size ranged from 6 to 11 mm. Microscopic analysis showed compound, but mainly dermal melanocytic nevi, all presenting a deep dermal expansion with fascicules of amelanotic spindled cells floating in a myxoid background. Cytologic atypia and mitotic activity were low. The superficial portion was either of spitzoid or nevoid cytology with a limited junctional component. In the initial case, the dermal myxoid component was predominant with rare, barely visible, superficial melanocytic nests. This peculiar morphology was responsible for a delayed diagnostic, which required an extensive panel of antibodies ruling out most, potentially myxoid, soft tissue tumors. We later observed the presence of similar, but more limited, dermal morphologic features in 3 other cases. Immunohistochemistry in the deep myxoid areas was melanA, ALK, SOX10, and MiTF. Molecular studies confirmed the ALK rearrangement by an ALK break-apart fluorescence in situ hybridization technique and by RNA sequencing. The latter identified 4 different 5'-fusion partners. Two gene fusions were undescribed: FBXO28(e2)-ALK(e19) and NPAS2(e2)-ALK(e19), and 2 previously described: TPM3(e7)-ALK(e20) and PPFIBP1(e9)-ALK(e19). No relapse or metastatic evolution was seen during follow-up (3 to 24 mo). We denominated this potentially challenging new variant of compound nevus linked to a kinase fusion: Melanocytic Myxoid Spindle Cell Tumor with ALK Rearrangement.

Metastatic malignant peripheral nerve sheath tumour presenting as a spontaneous extradural haematoma - A case report.

Malignant peripheral nerve sheath tumours may arise from any cranial or somatic nerve. The median survival with best therapy is 49 months. The present case reports a patient with an MPNST that exhibited an unusually indolent behaviour. Besides this, the patient developed a dural metastasis from the lesion and presented with a spontaneous extra-dural haematoma. This has not been reported hitherto in literature.

Spindle cell oncocytoma of the adenohypophysis: two case reports and a review of the literature.

Spindle cell oncocytoma (SCO) of the adenohypophysis is a rare tumor in the sellar region. Due to its rarity, little information is available regarding SCO. It is often misdiagnosed as another type of sellar tumor. In the present study, two cases of SCO were reported. One patient was a 35-year-old female presenting with decreased visual acuity, amenorrhea and lactation. The other patient was a 62-year-old female with no clear symptoms or signs. Cranial magnetic resonance imaging (MRI) revealed a suprasellar mass with marked homogeneous enhancement in the two cases. A craniotomy was performed to completely resect the tumors. The tumors were immunopositive for vimentin, epithelial membrane antigen (EMA), S-100 and thyroid transcription factor-1 (TTF-1). The tumors were pathologically diagnosed as SCO. No recurrence occurred during the follow-up period of 15-21 months. In the present study, the literature was reviewed and the clinical data, imaging features, intraoperative findings and recurrence of 24 cases were analyzed in the literature as well as the present two cases. The average age of the SCO patients was 58.5 years and no gender preference was observed for the disease. The tumor exhibited homogeneous enhancement on the MRI. The intraoperative assessment revealed that the tumor had a rich blood supply and the SCO tumors were immunopositive for vimentin, S-100, EMA and TTF-1. These findings provided valuable clinical data for the preoperative diagnosis and surgical removal of SCO tumors.

Re-appraisal of risk classifications for primary gastrointestinal stromal tumors (GISTs) after complete resection: indications for adjuvant therapy.

BACKGROUND: A substantial number of localized gastrointestinal stromal tumor (GIST) patients have recurrences even after complete resection. The risk of recurrence after complete resection should be estimated when considering adjuvant therapy. In this study, we evaluated prognostic factors of GIST recurrence and compared several reported risk-stratification schemes for defining risk of recurrence to guide the use of adjuvant therapy using data from a large Japanese GIST population. METHODS: We analyzed clinicopathological data collected retrospectively and prospectively from 712 GISTs with complete resection from 1980-2010. We evaluated possible prognostic factors and compared the National Institutes of Health consensus criteria, the Armed Forces Institute of Pathology criteria, Joensuu's modified NIH classification (J-NIHC), the American Joint Committee on Cancer staging system (AJCCS), and the Japanese modified NIH criteria for prediction of tumor recurrence in adjuvant settings. RESULTS: Univariate analysis suggested that the following factors were prognostic: tumor size, mitotic count, site, clinically malignant features of rupture and/or invasion, and gender. In multivariate analysis, size >5 cm, mitotic count >5/50 HPF, non-gastric location, and the presence of rupture and/or macroscopic invasion were independent adverse prognostic factors. When adjuvant therapy is considered for patients with high-risk GIST, the J-NIHC was the most sensitive classification system, while the AJCCS appeared to be the most accurate for predicting recurrence. CONCLUSION: Tumor size, mitotic count, tumor site, and clinical features of rupture and/or invasion were important prognostic factors for GIST recurrence. Joensuu's classification appeared to best identify candidates for adjuvant therapy.

Nodular fasciitis of the breast.

Nodular fasciitis of the breast is a rare, benign, soft-tissue tumor that can clinically and radiologically mimic invasive ductal carcinoma. A 25-year-old woman presented with a palpable lesion in the lower inner aspect of the left breast. Radiologically, breast carcinoma could not be excluded. On examination of the core needle biopsy, the tumor was characterized histologically as a spindle cell tumor. Excisional biopsy was performed. The tumor was diagnosed as nodular fasciitis of the breast. The imaging and histological findings of this case are presented.

Nevo de células fusiformes de Reed na conjuntiva / Spindle cell nevus of Reed in the conjunctiva

Os autores relatam um caso de nevo de Reed, lesão que apresenta aspecto histológico de malignidade, mas tem evolução benigna. Paciente de 48 anos, masculino, cor parda, apresentava pterígio nasal no olho direito, associado a uma lesão pequena e pouco pigmentada localizada na cabeça do mesmo. Realizou-se exérese de ambos, sem intercorrências, sem sinais de recidiva. O exame histopatológico revelou lesão com bordas definidas, restrita ao epitélio, constituída por células fusiformes perpendiculares à superfície, com pigmentação melânica esparsa. O diagnóstico inicial foi nevo de Spitz, mas, posteriormente, chegou-se à conclusão que se tratava do nevo de células fusiformes de Reed. O presente relato é o segundo na literatura mundial e o primeiro no Brasil.

The authors report one case of nevus of Reed, which has histological aspect of malignancy, but a benign evolution. A 48-years-old brown skin male presented nasal pterygium in right eye, associated with a small and poorly pigmented lesion located on the pterygium head. Both were excised without complications and, currently, there is no recidivation. The histopathological examination revealed one lesion with defined edges, limited to the epithelium, consisted of spindle cells perpendiculars to the surface and with sparse melanin pigmentation. The initial diagnosis was Spitz nevus, but, afterwards, we concluded that was the spindle cell nevus of Reed. This report is the second in the international literature and the first in Brazil.

Mutational status of KIT and PDGFRA and expression of PDGFRA are not associated with prognosis after curative resection of primary gastrointestinal stromal tumors (GISTs).

BACKGROUND: The aim of this study was to investigate if immunohistochemical expression and mutational status of KIT and PDGFRA in GISTs are associated with the clinical course and disease-free survival after curative resection of the primary tumor without adjuvant systemic therapy. METHODS: Paraffin-embedded tumor sections of 95 GISTs were analyzed for KIT and PDGFRA expression by immunohistochemistry. PDGFRA expression was judged using a scoring system subdividing tumors in negative/weak and strong immunoreactivity groups. For mutation analysis, exons 9, 10, 11, 13, and 17 of KIT and exons 10, 12, 14, and 18 of PDGFRA were sequenced. RESULTS: Of 95 R0-resected GISTs, 69% showed strong PDGFRA immunoreactivity. Gastric GISTs revealed a significantly higher rate of strong PDGFRA immunoreactivity (P = 0.01) and longer DFS (P = 0.015) than GISTs of the small intestine. KIT mutations were detected in 43 of 63 (68.3%) completely sequenced cases while PDGFRA mutations were identified in 6 cases (10%). In multivariate analysis, neither KIT/PDGFRA expression nor mutational status of KIT or PDGFRA were independent prognostic factors. Only mitotic rate predicted recurrence independently. CONCLUSION: Our data do not support the notion that expression of PDGFRA or mutations in KIT or PDGFRA are independent prognostic factors after curative resection of primary GIST.

Extragastrointestinal stromal tumor and liver transplantation: case report and review.

The occurrence of de novo malignant neoplasias has been shown in postransplant patients under imunosuppression. It is the second leading cause of late death in liver transplant recipients. The greatest incidence is seen in cancers associated with chronic infection by human papilloma virus, skin cancers, oropharyngeal, and gastrointestinal (GI) malignancies. GI stromal tumors (GISTs) are the most common mesenchymal tumors of the GI tract. Rare cases are identified outside the GI tract are collectively known as extragastrointestinal stromal tumors (EGISTs). We present an EGIST case in a liver transplantation patient. A 64-year-old man underwent liver transplantation because of cirrhosis (hepatitis B virus and alcoholism) and hepatocellular carcinoma. Histopathologic findings revealed 2 trabecular hepatocellular carcinomas: a 3.5-cm-diameter lesion located at segment VIII and another 2-cm one at segment V. Seven months later, he noticed a hardened, mobile, painless, 3-cm subcutaneous nodule in the perineum localized in the right lateral quadrant 2 cm distant from the anus. A surgical resection with 1 cm margin yielded a histopathology report of a 5.0 x 3.0 cm spindle cell stromal tumor. The immunohistochemical profile was compatible with a GIST, with 5 mitosis per 50 high-powered fields. This tumor is extremely rare after liver transplantation but has shown a good outcome up to now.

[Cases of primary multiple metachronous skin melanoma].

The article presents medical cases of primary multiple metachronous skin melanoma, which is rarely come across in oncological practice and presents interest for oncologists.

Post-traumatic spindle cell nodule misdiagnosed as a herniation of the buccal fat pad.

We studied a quasi-neoplastic lesion that developed in the oral mucosa secondarily to trauma. The female patient, 2 years of age, presented with a rapidly growing nodule and the lesion was diagnosed as a herniation of the buccal fat pad. Following partial resection, no recurrence was seen. The ulcerated polypoid mass was composed of compact spindle-cell proliferation with invasion of underlying muscle and fat. Atypical stromal cells were present in the myxoid areas. The surface edematous stroma contained abundant granulation tissue-type vascularity and a mixed population of chronic inflammatory cells. On immunohistochemical study, the spindle cells were consistent with myofibroblasts. The morphologic features, proliferating cell type, and benign clinical course are identical to the post-operative spindle cell nodules that occur in the genitourinary tract.

Pigmented spindle cell naevus of reed presenting in the conjunctiva.

PURPOSE: This study aimed to present the clinical and histopathological features of a pigmented spindle cell naevus (PSCN) appearing in the conjunctiva. METHODS: Histopathological examination of the lesion following excision and review of the pertinent literature. RESULTS: The features were consistent with those previously recognized in the skin as the PSCN of Reed. CONCLUSION: The PSCN can appear in the conjunctiva and should not be confused with conjunctival melanoma.