Talk:Germ cell tumor

Overlapping pages
These pages have text overlapping with this page, and others; distribute the text among other pages. --Una Smith 19:19, 1 July 2007 (UTC)


 * Germ cell ovarian cancer: distribute between ovarian cancer and germ cell tumor.  Done --Una Smith 22:43, 5 July 2007 (UTC)
 * Mediastinal germ cell tumor: distribute between mediastinal tumor (or similar) and germ cell tumor

text from germ cell ovarian cancer
moved here pending incorporation into this article, or deletion. --Una Smith 22:39, 5 July 2007 (UTC)

Ovarian Germ Cell Tumors can be divided into three major groups: (1) benign tumors (usually dermoid cysts); (2) malignant tumors that arise from dermoid cysts; and (3) primitive malignant germ cell tumors including dysgerminoma, yolk sac tumors, immature teratomas, embryonal carcinomas, and choriocarcinoma.

Dysgerminoma of the ovary is the female counterpart of the seminoma in the male. It occurs primarily in young females and accounts for about 30-40% of germ cell tumors. Grossly, the tumor is rather rubbery in consistency, smooth, rounded, and thinly encapsulated, with a brown or grayish-brown color. This neoplasm is unilateral in 85-90% of cases. It is a solid neoplasm, which may contain areas of softening due to degeneration.

Histologically, dysgerminoma mimics the pattern seen in the primitive gonad, ie, it has nests of germ cells that appear as large, rounded cells with central nuclei that contain one or two prominent nucleoli surrounded by undifferentiated stroma (Fig 49-6). Lymphocytes may invade the stroma and occasionally giant cells are identified. A lymphocytic infiltrate is considered a favorable prognostic indicator.

Endodermal sinus tumor of the ovary, previously called a yolk sac tumor, is the second most common germ cell neoplasm, occurring in approximately 20% of cases.

Mature cystic teratoma (dermoid cyst) are the most common germ cell tumors and in this case all tissue is developmentally mature and there is little or no risk of malignancy. Patients may be asymptomatic or present abdomino-pelvic pain or increasing abdominal girth or a palpable abdominal mass.

Dysgerminoma. Dysgerminomas are the most frequent malignant germ cell tumors in young women (80% of cases). They are rarely pure dysgerminomas but are often mixed with other cell types and synciotrophoblastic types secreting hCG.

Endodermal sinus tumor (yolk sac tumor). These are an association of extra-embryonic mesodermal cells and endodermal cells. The mean age at diagnosis is 19 years and the incidence appears to increase with age.

Gonadoblastoma of the ovary is a rare neoplasm composed of nests of germ cells and sex cord derivatives that are surrounded by connective tissue stroma.

Other Tumors. Other tumors include embryonic carcinomas consisting of extra-embryonic and embryonic teratoma-type pluripotential cells.

cleanup text from testicular cancer

 * Germ-cell tumors are classified as either seminomas or nonseminomas (which may be called teratomas in the UK). Seminomas are slow-growing. Seminomas, when found, tend to be localized (i.e., only in the testicles), simply because they spread relatively slowly. Nonseminomas, on the other hand, tend to spread more quickly.  Nonseminomas are further classified into four subtypes; embryonal carcinomas, choriocarcinomas, yolk sac tumors, teratomas and mixed tumors. Their appearance under the microscope and also their gene expression is rather distinguished from each other, their rate of spread varies somewhat, but they are nevertheless treated similarly.  When seminomas and nonseminomas are both present (which is not unusual), the cancer is classified as nonseminoma.


 * Blood markers for testicular tumors include the beta subunit of human chorionic gonadotropin (βhCG), lactate dehydrogenase (LDH), and alpha-fetoprotein (AFP). Seminomatous tumors never present elevated AFP levels. Placental alkaline phosphatase and other markers are sometimes used by the pathologist to differentiate between seminoma and nonseminomatous tumors.

Most of the above text from testicular cancer duplicates text already here, but a phrase or two may be of use. Integrate into the article, or delete. --Una Smith 16:07, 29 July 2007 (UTC)

Genetics

 * Most germ cell tumors have a chromosome count in the hypo to hyper triploid range (i.e. 60-70 chromosomes per cell nucleus in stead of the normal 46). About 80 % of these tumors also have a specific marker chromosome called isochromosome 12p. This is a chromosome where the shortest "arm" of chromosome 12 (12p) is present on both sides of the same centromer. Among germ cell tumors not having the isochromosome 12p, almost all have increased DNA copy number of 12p through other means. Thus, in tumors with unknown origin, increased DNA copy number of 12p is used as a marker for germ cell origin. The general gene expression patterns are clearly distinguishing the various histological subtypes of germ cell tumors. For example, in embryonal carcinomas, the same genes are overexpressed as are found highly expressed in embryonic stem cells. Further, AFP is a gene specifically expressed from yolk sac tumor, and CGB (encoding HCG) and other "pregnancy related genes" are specifically expressed from choriocarcinomas.

This text from testicular cancer needs to be rewritten (and cite sources!): it applies primarily to post-pubescent testicular germ cell tumors;  these specific chromosome abnormalities usually do not occur in testicular germ cell tumors of babies and children, nor in post-pubescent germ cell tumors in other locations. --Una Smith 16:31, 29 July 2007 (UTC)

Congenital
"A congenital disorder is any medical condition that is present at birth." I wonder if there are any papers that can prove congenital origin of germ cell tumors. -GCTalk —Preceding unsigned comment added by GCTalk (talk • contribs) 02:39, 4 December 2007 (UTC)


 * Germ cell tumors have been diagnosed in utero; some even require treatment in utero.  --Una Smith 14:38, 4 December 2007 (UTC)

Is there any evidence what is the prevalence or incidnce of GCT in utero? - GCTalk —Preceding unsigned comment added by GCTalk (talk • contribs) 15:28, 4 December 2007 (UTC)

Yes. I have edited the article to mention just one specific type of germ cell tumor with abundant record in utero. Does this get at your question? --Una Smith 16:39, 4 December 2007 (UTC)

Yes, thank you. I found papers about this specific type of GCT. How about many other extragonadal germ cell tumors in adults. Are they all from congenital origin? —Preceding unsigned comment added by GCTalk (talk • contribs) 20:12, 4 December 2007 (UTC)


 * Another good question for this article. I have not looked far into it, but I have seen two lines of evidence offered to support the theory that all extragonadal GCTs in humans are congenital:
 * Laboratory research in mice, tracing cell lines, indicate these tumors are the result of early errors of development, not "dedifferentiation" as is often the case with other kinds of cancers
 * The "midline head to tail" distribution of these tumors in humans, regardless of age at diagnosis

GCTalk, if you follow this lead and find some relevant papers, please cite them here. Thanks! --Una Smith (talk) 22:12, 4 December 2007 (UTC)

Personally, in case of adults or teenagers I think it is more likely to be a consequence of events that happen few weeks or months before cancer develops. I would like only encourage scientists to go to this direction. It is too early to say that all extragonadal GCTs may have only congenital origin in adults - I do not know papers that can support it. —Preceding unsigned comment added by GCTalk (talk • contribs) 21:52, 5 December 2007 (UTC)


 * I have read a significant portion of the literature on germ cell tumors and I can assure you there is no evidence supporting the idea that these tumors are "a consequence of events that happen few weeks or months before cancer develops". On the contrary, there are many, many case reports of tumors discovered in people who complained of related symptoms for years but their complaints were dismissed. --Una Smith (talk) 20:08, 6 December 2007 (UTC)

Classification
The pick age distributions by testis cancer type in Southeast England between 1960 and 2004 was: 30-40 for seminoma and 20-35 for non-seminoma. Source: British Journal of Cancer (2007) 96, 529 – 533, Figure 1.

In Wikipedia Germ Cell Tumor article the pick age for Germinoma including dysgerminoma and seminoma is 40-50. Is it correct information for all countries? —Preceding unsigned comment added by (GCTalk (talk)

Research on chemo-resistant GCT
[http://www.cancernetwork.com/asco-2016-genitourinary-cancers-symposium/study-identifies-molecular-targets-chemo-resistant-germ-cell-tumors Study Identifies Molecular Targets in Chemo-Resistant Germ Cell Tumors. Jan 2016] looks interesting but not sure where to mention it in the article. - Rod57 (talk) 14:13, 1 March 2016 (UTC)

Lancet review
10.1016/S0140-6736(15)00991-5 JFW &#124; T@lk  13:14, 25 April 2016 (UTC)