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Pigmented tumors are rare neoplasm of central nervous system. Melanocytic tumor, including primary and metastatic lesions, is the most common type. Owing to the rarity, the differential diagnosis of pigmented tumors and clinical management of melanocytic tumor remain challenge. Therefore, focusing on melanocytic tumors, the clinical, radiological, histopathological features and treatment outcomes were presented and analyzed in this study. We identified 22 melanocytic tumors, 2 melanotic medulloblastomas, 2 melanotic ependymomas and 1 melanotic schwannoma. Compared with metastatic melanocytic tumors (MMTs), primary melanocytic tumors (PMTs) were characterized by younger age (36.11 ± 17.96 vs. 51.69 ± 12.58 years, p = 0.0262), lower possibility to be multiple lesions (11.1%vs. 61.5%, p = 0.0306), higher proportion of hypointensity on T2-weighted images (66.7% vs. 15.4%, p = 0.0260) and higher frequency in black appearance (77.8% vs. 23.1%, p = 0.0247). During the follow-up, 4 PMTs and 11 MMTs (71.4%) experienced tumor progression. PMTs had better prognosis than MMTs that progression-free survival (PFS) rate of PMT was 50.0% but decreased to 23.1% for MMTs at 12 months (p = 0.0123). Cox proportional hazards regression revealed that multiplicity of tumor was an independent predictor for PFS. None of patient with multiple tumors was in PFS after 12 months’ follow-up whereas PFS rate was 40.5% for single tumor (p = 0.0002). In conclusion, radiological appearances, especially hypointensity on T2-weighted images, might be an indication for PMT. MMTs are more likely to be multiple intraparenchymal masses in elder patients located in supratentorial region. Current treatments included operation, radiotherapy and chemotherapy are not competent to control tumor progression and other therapeutic modalities are urgently needed.

Although pituitary adenomas (PAs) are regarded as benign neoplasm, efficient postoperative management of PAs, especially invasive PAs, is still a major challenge for neurosurgeons. Thus, in order to verify the effect of postoperative surveillance alone for invasive PAs and identify helpful predictive factors of relapse after initial surgery, a series of 107 cases of surgically gross-totally resected invasive PAs were retrospectively investigated. With regarded to pituitary function, the preoperative incidence of hypothyroidism was higher than that of hypoadrenocorticism and hypogonadism (66.4% vs. 31.8% and 29.9%; p 0.001). Tumors extended into sphenoid sinus or cavernous sinus may be less likely to develop hypoadrenocorticism or hypogonadism. Postoperative relapse was found in 35 cases (32.7%) during a median follow-up of 27 months. The overall relapse rates were 12.3, 28.9 and 38.4% at 1, 3 and 5 years, respectively. Tumor size was the exclusive independent risk factor for relapse. Higher relapse rates presented in large invasive PAs (more than 3.45 cm) were 24.5, 48.9 and 59.2% at 1, 3 and 5 years, respectively. In conclusion, preoperative larger tumors shared significantly higher risk of relapse after initial surgical total resection. Due to the relatively high relapse rate, close surveillance should be executed in strict rotation in postoperative management of gross-totally resected invasive PAs. Moreover, special attention should be payed to tumors with diameter of more than 3.45 cm for more than half of them relapsed in 5 years.

Objective Atypical pituitary adenomas were relatively more malignant lesions defined by WHO criteria. However, not all of them show clinically aggressive behavior. Thus, the current WHO criteria of atypical adenoma didn’t seem to be enough to distinguish clinically aggressive adenoma. Therefore, we would like to identify other clinical factors in a cohort of atypical pituitary adenomas to a better identification of clinical aggressiveness. Patients and Methods In order to verify predictors of clinically aggressive phenotype among atypical pituitary adenomas, we retrospectively analyzed the clinical characteristics and therapeutic outcomes of consecutive 49 cases. Results Totally, 26 cases were identified as clinically aggressive pituitary adenoma. Clinically aggressive lesions were more likely to be functional (46.2% vs. 17.4%, p = .0388) and be detected in males (65.4% vs. 21.7%, p = .0037). Clinically aggressive adenomas also had higher Ki-67 index [5.0 (5.3)% vs. 4.1 (1.3)%, p = .0011] and presented bigger tumor size [11.83 (11.95) cm3 vs. 5.39 (6.08) cm3, p = .0174]. In multivariate analysis, gender (p = .017), functional status (p = .009) and Ki-67 index (p = .024) were independent predictors of clinical aggressiveness. Further analysis revealed that Ki-67 index of more than 4.45% was associated with worse progression-free survival. Conclusions Gender, functional status, tumor size and Ki-67 index ≥ 4.45% were associated with clinical aggressiveness. A clinicopathological classification of pituitary adenomas may be useful to determine who should be under closer radiological follow-up or followed multimodal treatment strategy.

The purpose of this study was to discuss shape, scale and superimposed types of sandy gravel bodies in sandy-gravel braided distributary channel. Lithofacies analysis, hierarchy bounding surface analysis and subsurface dense well pattern combining with outcrops method were used to examine reservoir architecture patterns of sandy gravel braided distributary channel based on cores, well logging, and outcrops data, and the reservoir architecture patterns of sandy gravel braided distributary channels in different grades have been established. The study shows: (1) The main reservoir architecture elements for sandy gravel braided channel delta are distributary channel and overbank sand, while reservoir flow barrier elements are interchannel and lacustrine mudstone. (2) The compound sand bodies in the sandy gravel braided delta distributary channel take on three shapes: sheet-like distributary channel sand body, interweave strip distributary channel sand body, single strip distributary channel sand body. (3) Identification marks of single distributary channel include: elevation of sand body top, lateral overlaying, “thick-thin-thick” feature of sand bodies, interchannel mudstone and overbank sand between distributary channels and the differences in well log curve shape of sand bodies. (4) Nine lithofacies types were distinguished in distributary channel unit interior, different channel units have different lithofacies association sequence.

This paper discusses the overall distribution characteristics of alluvial fan in the Triassic Lower Karamay Formation, Yizhong Area, the Karamay Oilfield, with core, outcrop, logging and seismic data. On this basis, the shapes, sizes and stacking patterns of intercalations in different levels and sub-facies are analyzed using the hierarchy bounding surfaces method. In the study area, the Lower Karamay Formation contains (from bottom to top) root fan, middle fan and outer fan deposits, with size-reducing grains, as a complete retrograding sedimentary sequence. The intercalation in the alluvial fan reservoir can be divided into two types: lithological intercalation (fine sediments) and physical intercalation (argillaceous sandstone/conglomerate). Origin, pattern and size of intercalations vary significantly in different sub-facies zones. In particular, the intercalations in root fan are “scattered generally and interlaced locally”, presenting as partially discontinuous screen in a high-permeable network; the intercalations in middle fan are relatively stable intercalations and lateral intercalations, with a higher capacity to shade or screen the seepage; the intercalations in outer fan present as a layered cake, with reservoir bodies mosaic-like along the source and lenticular in perpendicularity to the source that are separated by thick barrier beds, showing the highest capacity of screen. Key words: Karamay Oilfield, Lower Karamay Formation, alluvial fan, intercalation, root fan, middle fan, outer fan