A rare tumour of the vulva: a case report of a vulva angioneurofibroma hamartoma in a Cameroonian woman

We present the case of a rare vulva tumour, in a 33 years Cameroonian old woman and managed in Obstetrics and Gynecology Unit of Yaoundé Central Hospital in Cameroon. It was a painless pedunculated vulva tumour which developed over a period of six months. This gigantic rapidly growing tumour, was treated with simple surgical resection. After surgical resection, histology confirmed an angioneurofibroma hamartoma. There has been no recurrence and presently the patient is symptom-free.Key words: Tumour, vulva, ngioneurofibroma hamartom

Medullary and papillary carcinoma of the thyroid gland occurring as a collision tumor with lymph node metastasis: A case report

<p>Abstract</p> <p>Introduction</p> <p>Papillary thyroid carcinoma and medullary thyroid carcinoma are two different thyroid neoplasia. The simultaneous occurrence of medullary thyroid carcinoma and papillary thyroid carcinoma as a collison tumor with metastases from both lesions in the regional lymph nodes is a rare phenomenon.</p> <p>Case presentation</p> <p>A 32-year-old Iranian man presented with a fixed anterior neck mass. Ultrasonography revealed two separate thyroid nodules as well as a suspicious neck mass that appeared to be a metastatic lesion. The results of thyroid function tests were normal, but the preoperative calcitonin serum value was elevated. Our patient underwent a total thyroidectomy with neck exploration. Two separate and ill-defined solid lesions grossly in the right lobe were noticed. Histological and immunohistochemical studies of these lesions suggested the presence of medullary thyroid carcinoma and papillary thyroid carcinoma. The lymph nodes isolated from a neck dissection specimen showed metastases from both lesions.</p> <p>Conclusions</p> <p>The concomitant occurrence of papillary thyroid carcinoma and medullary thyroid carcinoma and the exact diagnosis of this uncommon event are important. The treatment strategy should be reconsidered in such cases, and genetic screening to exclude multiple endocrine neoplasia 2 syndromes should be performed. For papillary thyroid carcinoma, radioiodine therapy and thyroid-stimulating hormone suppressive therapy are performed. However, the treatment of medullary thyroid carcinoma is mostly radical surgery with no effective adjuvant therapy.</p

Endogenous Market Structure and Trade

Many agricultural products are exported from a small number countries and few export traders are typically involved. This is the case for maple syrup whose production takes place in eastern Canada and in the northeastern part of the United States. Corner solutions in oligopoly models usually arise because of asymmetries in trade and procurement costs. Such asymmetries can be ruled out in the case of Canadian and US maple syrup exports, yet many importing countries purchase only either from Canada or from the US. A theory of endogenous market structures based on duopoly competition with fixed costs is developed. It explains many stylized facts including that large markets have a higher probability of accommodating duopoly competition while smaller markets are more likely to “naturally” attract a single entrant or no entrant at all. A random parameter multinomial logit model is used to explain market structure and probability estimates are used to correct for potential selection biases in market-structure-specific gravity equations