Automatic Small Bowel Tumor Diagnosis by Using Multi-Scale Wavelet-Based Analysis in Wireless Capsule Endoscopy Images

BACKGROUND: Wireless capsule endoscopy has been introduced as an innovative, non-invasive diagnostic technique for evaluation of the gastrointestinal tract, reaching places where conventional endoscopy is unable to. However, the output of this technique is an 8 hours video, whose analysis by the expert physician is very time consuming. Thus, a computer assisted diagnosis tool to help the physicians to evaluate CE exams faster and more accurately is an important technical challenge and an excellent economical opportunity. METHOD: The set of features proposed in this paper to code textural information is based on statistical modeling of second order textural measures extracted from co-occurrence matrices. To cope with both joint and marginal non-Gaussianity of second order textural measures, higher order moments are used. These statistical moments are taken from the two-dimensional color-scale feature space, where two different scales are considered. Second and higher order moments of textural measures are computed from the co-occurrence matrices computed from images synthesized by the inverse wavelet transform of the wavelet transform containing only the selected scales for the three color channels. The dimensionality of the data is reduced by using Principal Component Analysis. RESULTS: The proposed textural features are then used as the input of a classifier based on artificial neural networks. Classification performances of 93.1% specificity and 93.9% sensitivity are achieved on real data. These promising results open the path towards a deeper study regarding the applicability of this algorithm in computer aided diagnosis systems to assist physicians in their clinical practice.

Tumor de Buschke-Löwenstein: um Caso em Doente com Coinfeção Vírus da Imunodeficiência Humana e Vírus Papiloma Humano

O tumor de Buschke-Löwenstein (TBL) é uma variante rara de condiloma acuminatum que possui comportamento maligno pelo crescimento local, mas não apresenta potencial metastático. Afeta primariamente a área genital e, menos frequentemente a região perianal. Os fatores de risco para o seu desenvolvimento incluem a terapêutica imunossupressora e a infeção VIH. Possui elevada taxa de recorrência e de transformação maligna, sendo a cirurgia o tratamento inicial recomendado. Apresenta-se um caso de TBL perianal e anal num doente com infeção VIH cuja histologia não revelou transformação maligna e para o qual a terapêutica cirúrgica isolada foi eficaz. Revê-se o conhecimento atual sobre esta entidade tendo em atenção a história natural nos indivíduos infetados pelo VIH.

Ovarian Borderline Tumor and Fertility-Sparing Surgery

Ovarian borderline tumors (OBTs) are frequently diagnosed in women of reproductive age. There is no consensus about their management, and it sometimes represents a dilemma aboutwhat should be done: fertility sparing surgery or a hysterectomy with salpingo-oophorectomy? Case: A 32-year-old nulligravida, diagnosed with a right ovarian borderline tumor is presented. She underwent pelvic washings, right salpingo-oophorectomy, appendectomy, and omental and peritoneal biopsies (laparotomic approach). Macroscopically, the left ovary was normal and subsequent exploration for staging was also normal, including the lymph nodes. Intraoperatively, frozen section examination was unclear, suggesting an OBT. Results: The final histopathologic diagnosis was ovarian borderline tumor, stage IIC (International Federation of Gynecology and Obstetrics [FIGO] staging). The patient expressed a desire to preserve her fertility. Thirty-six months postsurgery, she became pregnant spontaneously and delivered a healthy newborn at term. Conclusions: Conservative surgery can be performed in young patients treated for an OBT, provided they are closely followed up and that this surgery is performed after careful consideration and informed consent. It is, however, controversial with respect to performing hysterectomy and salpingo-oopherectomy upon the patient’s completion of childbearing.

A Rare Abdomino-Pelvic Tumor: Paraganglioma

Paragangliomas are rare tumors, with a reported incidence of 2–8 per million. They are chromaffin cell tumors that develop from the neural crest cells and may be divided in tumors derived from the parasympathetic or sympathetic ganglia. We report a case a of a 32-year-old nulliparous woman, referred to our Infertility Clinic. Abdomino-pelvic ultrasound identified a large abdominopelvic tumor, without ovarian origin (both ovaries were identified and had normal morphology). Magnetic Resonance Imaging suggested a right adnexal multicystic, vascularized mass close to iliac vessels and questioning an ovarian origin. At exploratory laparotomy, a 10 cm encapsulated and vascularized mass was found beginning just below right renal artery and extending to the level of the broad ligament. This mass was totally excised and histopathology was consistent with Paraganglioma.

Apresentação Curiosa de um Tumor Cutâneo e o seu Sucesso Terapêutico

A doença de Bowen é um carcinoma espinocelular (CEC) in situ que pode evoluir para carcinoma espinocelular invasivo. Mulher, 61 anos, referia placa rosada, anular, bem delimitada, não descamativa, na região pré-auricular direita com 2 anos de evolução. Desde 2 meses antes da consulta, surgiu no seu centro um nódulo translúcido, com telangiectasias. A biopsia excisional do nódulo mostrou carcinoma espinocelular com doença de Bowen na periferia. A placa remanescente foi tratada com laser de CO2 seguida de terapêutica fotodinâmica com desaparecimento completo da lesão. Salienta-se este caso pela curiosidade da sua apresentação clínica e pelos bons resultados terapêutico e estético.

Identification of de Novo Germline Mutations in the HRPT2 Gene in Two Apparently Sporadic Cases with Challenging Parathyroid Tumor Diagnoses

The diagnosis of parathyroid carcinomas is often difficult. HRPT2 mutations have been identified in familial [hyperparathyroidism-jaw tumor (HPT-JT) syndrome] and sporadic parathyroid carcinomas, supporting that HRPT2 mutations may confer a malignant potential to parathyroid tumors. In this study, we report the clinical, histopathological, and genetic investigation of two unrelated cases, whom had apparently sporadic malignant parathyroid tumors, initially diagnosed as adenomas. In one case, the differential diagnosis was complicated by cervical seeding of parathyroid tumor cells. Genetic studies identified de novo HRPT2 germline mutations in cases 1 (c.518_521delTGTC [p.Ser174LysfsX27]) and 2 (c.226 C > T [p.Arg76X]), unveiling the hereditary HPT-JT syndrome in both patients. Furthermore, the identification of somatic mutations in the patients‟ parathyroid tumors provided evidence for complete inactivation of the HRPT2 gene, which was consistent with the tumor malignant features. The sensitivity of parafibromin immunostaining to detect HRPT2 mutations was limited. The present data suggests that patients with apparently sporadic parathyroid carcinomas, or parathyroid tumors with atypical histological features, should undergo molecular genetic testing, as it may detect germline HRPT2 mutations. Establishing the diagnosis of hereditary HPT-JT syndrome is relevant for clinical counseling and management of the carriers and their relatives.