Genitourinary Cancer – 4 – GCTs at other sites
Genitourinary Cancer – 4
(All the articles published in past are available at www.shyamhemoncclinic.com/blog/)
Question: Thank you Chiragbhai for more interesting points about Testicular cancer: 1. After so many decades, BEP regimen (bleomycin, etoposide, cisplatin) still is the Best, and has not been replaced by new medicines. For lower risk patients, EP can be given instead of BEP however which has less side effects. 2. Nonseminoma overall cure rate is 90%. 3. For those who relapse, salvage chemotherapy provides good long term control in about half of patients. And if second relapse, Autologus Stem Cell Transplant provides long term control in about 50% patients. And this requires two transplants in a row, known as tandem transplant. 4. All residual masses after chemotherapy need to be removed. PET-CT scan is not useful in differentiating live cancer versus dead tumor cells in this malignancy.
Now, I understand Yuvraj Singh, our famous cricketer, had Seminoma but his tumor was in lung. Can it originate in lung?
Answer: Interestingly Yuvraj Singh had Seminoma of mediastinum, technically not lung. Pure seminoma arising from mediastinum also has excellent cure rates like seminoma from testis.
Germ cell tumors can arise from not just testis, but also mediastinum and retroperitoneum. These are much less common and are primarily evaluated and treated in same manner as testicular germ cell tumors. It is important to obtain testicular ultrasound to ensure that is not the primary site.
There are few differences however:
- A proportion of these tumors are not associated with high tumor markers i.e. AFP or beta hCG.
- For nonseminoma, prognosis is not as good i.e. about 50% cure rate. (compared to 90% with testicular origin. Similar to poor risk testicular origin where also it is 50%).
- Residual masses less than 3 cm in these sites can be observed, especially if PET negative (of course with normal tumor markers).
- One very important difference is the need to avoid Bleomycin as far as possible, with mediastinal tumors. These patients may need major thoracic surgery, and prolonged high oxygen too. Bleomycin induced lung injury may put these patients at significant high risk of post operative morbidity and mortality. This has been well documented in series from Indian University. Hence preferred regimen in these patients is not BEP but VIP (etoposide, ifosfamide, cisplatin).
- Mature teratomas of mediastinum have better prognosis compared to testicular. They rarely contain malignant component and complete resection results in good cure rates.
- Radiation is rarely used for mediastinal tumors, due to higher long term risks of cardiovascular side effects (ischemic heart disease, valve disease, pericarditis), secondary cancers of the treated region.
- Mediastinal nonseminomatous germ cell tumors have a peculiar association with serious hematological disorders, in about 5% cases – such as AML, MDS, and rare ones like acute megakaryoblastic leukemia, malignant mastocytosis, malignant histiocytosis. These may develop within few years since diagnosis of GCT, and are mostly fatal.
Que: Very interesting. So Yuvraj Singh has excellent prognosis, right? Any other uncommon site for germ cell tumors?
Ans: Yes, Germ Cell Tumors arising from Ovary. Generally seen in young women, and essentially treated like testicular germ cell tumors. Monitoring is also similar using AFP, and beta HCG levels. About half are dysgerminoma. These are often limited to one ovary, and low grade. Fertility sparing surgery is possible in such cases. Higher stages, and most other histologies require chemotherapy, most commonly BEP combination (bleomycin, etoposide, cisplatin).
January 4th 2017.
Dr. Chirag A. Shah; M.D. Oncology/Hematology (USA), 079 26754001. Diplomate American Board of Oncology and Hematology. Ahmedabad. drchiragashah@gmail.com