Moran C A, Suster S
Department of Pulmonary and Mediastinal Pathology, Armed Forces Institute of Pathology, Washington, DC 20306-6000, USA.
Cancer. 1997 Aug 15;80(4):681-90.
Primary germ cell tumors of the mediastinum are unusual neoplasms with histopathologic features that are similar to those of germ cell tumors in the gonads. However, their clinical features, behavior, and spectrum of pathologic features in the mediastinum have not yet been fully defined.
The clinical and pathologic features of 322 cases of primary mediastinal germ cell tumors were reviewed, with special emphasis on teratomatous lesions. The tumors were divided into groups according to their histologic features and correlated with their order of frequency, patient gender and age distribution, and morphologic features. A clinical staging scheme based on the extent and location of the lesions was devised.
The overwhelming majority of patients were men (320); only 2 were women (both had teratomatous lesions with additional malignant components). The patients' ages ranged from 1 to 79 years (mean, 40 years). Histologically, all types of germ cell tumors were represented, including 138 teratomas (87 mature teratomas, 6 immature teratomas, and 45 teratomas with additional malignant components); 120 seminomas; 52 nonseminomatous, nonteratomatous germ cell tumors (38 yolk sac tumors, 6 embryonal carcinomas, and 8 choriocarcinomas); and 12 combined germ cell tumors without teratomatous components. The teratomatous lesions with additional malignant components were further separated into subtypes based on the histologic types of their malignant components, i.e., epithelial, mesenchymal, etc. Clinical staging was possible in 242 cases, with 191 cases (79%) in Stage I, 4 cases (1.6%) in Stage II, and 47 cases (19.4%) in Stage III. In each group, the clinical staging correlated well with the clinical outcome for the majority of patients.
The results of this study showed that mediastinal germ cell tumors have demographic and histopathologic distributions similar to those of tumors occurring in the male gonads, with teratomatous and seminomatous lesions being the most common. Among the nonseminomatous germ cell tumors in this study, the yolk sac tumors appeared to occur the most frequently (the ratio of yolk sac tumor occurrence to embryonal carcinoma occurrence was 6.1:1). In addition, the subclassification of teratomas with additional malignant components based on the histologic types of malignancies may lead to more therapy choices for patients. At the same time, the use of a clinical staging scheme may be of value in predicting clinical outcome and planning therapy.
纵隔原发性生殖细胞肿瘤是一种罕见的肿瘤，其组织病理学特征与性腺生殖细胞肿瘤相似。然而，它们在纵隔中的临床特征、行为及病理特征谱尚未完全明确。
回顾了322例原发性纵隔生殖细胞肿瘤的临床和病理特征，特别关注畸胎瘤病变。根据组织学特征将肿瘤分组，并与它们的发生频率顺序、患者性别和年龄分布以及形态学特征相关联。设计了一种基于病变范围和位置的临床分期方案。
绝大多数患者为男性（320例）；仅2例为女性（均有含其他恶性成分的畸胎瘤病变）。患者年龄范围为1至79岁（平均40岁）。组织学上，所有类型的生殖细胞肿瘤均有，包括138例畸胎瘤（87例成熟畸胎瘤、6例未成熟畸胎瘤和45例含其他恶性成分的畸胎瘤）；120例精原细胞瘤；52例非精原性、非畸胎瘤性生殖细胞肿瘤（38例卵黄囊瘤、6例胚胎癌和8例绒毛膜癌）；以及12例无畸胎瘤成分的混合性生殖细胞肿瘤。含其他恶性成分的畸胎瘤病变根据其恶性成分的组织学类型进一步分为亚型，即上皮性、间叶性等。242例患者可行临床分期，其中191例（79%）为I期，4例（1.6%）为II期，47例（19.4%）为III期。在每组中，临床分期与大多数患者的临床结局密切相关。
本研究结果表明，纵隔生殖细胞肿瘤在人口统计学和组织病理学分布上与男性性腺肿瘤相似，畸胎瘤和精原细胞瘤病变最为常见。在本研究的非精原性生殖细胞肿瘤中，卵黄囊瘤似乎最为常见（卵黄囊瘤与胚胎癌的发生率之比为6.1:1）。此外，根据恶性肿瘤的组织学类型对含其他恶性成分的畸胎瘤进行亚分类可能会为患者带来更多治疗选择。同时，使用临床分期方案可能有助于预测临床结局并规划治疗。
