An image-analysis system based on support vector machines for automatic grade diagnosis of brain-tumour astrocytomas in clinical routine.

An image-analysis system based on the concept of Support Vector Machines (SVM) was developed to assist in grade diagnosis of brain tumour astrocytomas in clinical routine. One hundred and forty biopsies of astrocytomas were characterized according to the WHO system as grade II, III and IV. Images from biopsies were digitized, and cell nuclei regions were automatically detected by encoding texture variations in a set of wavelet, autocorrelation and parzen estimated descriptors and using an unsupervised SVM clustering methodology. Based on morphological and textural nuclear features, a decision-tree classification scheme distinguished between different grades of tumours employing an SVM classifier. The system was validated for clinical material collected from two different hospitals. On average, the SVM clustering algorithm correctly identified and accurately delineated 95% of all nuclei. Low-grade tumours were distinguished from high-grade tumours with an accuracy of 90.2% and grade III from grade IV with an accuracy of 88.3% The system was tested in a new clinical data set, and the classification rates were 87.5 and 83.8%, respectively. Segmentation and classification results are very encouraging, considering that the method was developed based on every-day clinical standards. The proposed methodology might be used in parallel with conventional grading to support the regular diagnostic procedure and reduce subjectivity in astrocytomas grading.

Primary carcinoid of the testis with metastases. Case report and review of the literature.

Primary carcinoid of the testis is an extremely rare neoplasm, making up 0.23% of all testicular neoplasms. The vast majority of the reported cases are primary carcinoids and 20-25% are associated with teratomas. Approximately 10% of these tumors will develop metastases. We present a case of a 50-year-old man with a primary testicular carcinoid who developed lymph node and lung metastases 4 months after left inguinal orchidectomy. Our case was not associated with testicular teratoma or carcinoid syndrome. Vigorous efforts were done postoperatively to exclude the possibility of carcinoid tumor metastatic to the testis. Our patient achieved a mixed response (lung metastases: complete response, lymph node metastases: partial response) with combined therapy that included chemotherapy (cisplatin, etoposide, ifosfamide, epirubicin), octreotide and radiotherapy to the metastatic lymph nodes. He remains well and asymptomatic. We herein review the literature and discuss all the possibilities to explain the origin of carcinoid tumors of the testis.