| Breast Cancer Essay, Research Paper
Germ Cell Tumors
Germ cell tumors are formed from egg-making cells within the ovaries. They represent
approximately 3% of all ovarian cancers in Western countries. Germ cell tumors tend to
occur in young women, with a peak incidence among individuals who are in their early 20s.
Like testicular cancer, these tumors usually are very curable. In addition, they are
associated with specific markers (proteins) that are released into the blood, such as
beta-human chorionic gonadotropin (x-HCG) and alpha fetoprotein (AFP). After germ cell
tumors have been treated, the physician may conduct blood tests for x-HCG and/or AFP, to
determine whether the cancer is recurring (returning) (see also Treatment of Ovarian
Cancer).
Unlike patients with common epithelial tumors, 75% of whom are Stage 3 or 4 at diagnosis,
between 60% and 70% of patients with germ cell tumors are Stage 1; most remaining
patients are Stage 3 (Stages 2 and 4 are relatively rare for this tumor type) (see also
Ovarian Cancer Staging).
Germ cell tumors are divided into dysgerminomas and nondysgerminomatous types.
Dysgerminoma is the most common germ cell tumor, representing nearly one-half
of all cases. This tumor has been likened to the male testicular cancer known as
seminoma. A vast majority (some 80%) of dysgerminomas affect women younger
than 30, and roughly 20% of such tumors are diagnosed during pregnancy.
Nondysgerminomatous tumors are less common than dysgerminomas. Tumors in
this category include embryonal carcinoma, a very malignant, primitive form of
carcinoma; immature teratoma, a tumor made up of different tissues that are not
normally found in the ovary; choriocarcinoma, malignant tumor of the placental
epithelium; polyembryoma, a tumor formed from embryonic cells; and mixed germ
cell tumors, tumors containing a variety of cell types.
Sex Cord-Stromal Tumors
Sex cord-stromal tumors represent about 5% of all ovarian cancers. They are formed from
cells of the sex cord or mesenchyme (early connective tissue) within the embryonic gonad,
and they may contain gonad-related cells (e.g., granulosa cells, Sertoli cells, thecal cells) as
well as fibroblasts, which are immature, connective tissue-forming cells. The most common
tumors in this category are granulosa stromal cell tumors and Sertoli- or Sertoli-Leydig cell
tumors; other related tumors include lipid cell tumors and gynandroblastomas.
Granulosa stromal cell tumor is the most prevalent tumor in this category. It is more
common in postmenopausal women, and it may produce symptoms such as vaginal
bleeding and an elevated blood level of the tumor marker inhibin, a peptide hormone that
prevents the release of follicle stimulating hormone (FSH). Perhaps because of this,
individuals who have granulosa cell tumors often are diagnosed at an early stage (see also
Ovarian Cancer Staging).
Sertoli and Sertoli-Leydig cell tumors are very rare. Most patients with these tumors are
young; the average age is 25 years, with only 10% of individuals being over age 50. Pure
Sertoli cell tumors and pure Leydig cell tumors are benign; however, their malignant potential
is determined by their grade (see also Tumor Grade). Well-differentiated Sertoli-Leydig
tumors usually behave in a benign manner, whereas poorly differentiated tumors tend to be
malignant.
In general, sex cord-stromal tumors are associated with hormonal effects such as
virilization, the development of male secondary sex characteristics (e.g., a low voice, facial
hair); precocious puberty, early sexual maturity; amenorrhea, absence/stopping of the
menstrual period; or postmenopausal bleeding.
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