Stage I Testicular Cancer
Stage I Seminoma
Stage I seminoma has a cure rate that approaches 100% regardless of whether postorchiectomy adjuvant therapy is given.
Standard treatment options:
- Radical inguinal orchiectomy with no retroperitoneal node radiation therapy followed by chest x-rays and computed tomographic (CT) scans of the abdomen and pelvis (surveillance). These studies are typically performed every 4 months for the first 3 years, then every 6 months for 3 years, and then annually for an additional 4 years.
Results of multiple clinical series, including more than 1,200 patients with stage I seminoma managed by postorchiectomy surveillance, have been reported.[2-9] The overall 10-year tumor recurrence rate is 15% to 20%, and nearly all patients whose disease recurred were cured by radiation therapy or chemotherapy. Thus, the overall cure rate is indistinguishable from that achieved with adjuvant radiation therapy or carboplatin chemotherapy. Relapses after 5 years are unusual but can occur in as many as 4% of patients. Independent risk factors for relapse include tumor size greater than 4 cm and invasion of the rete testis. The 5-year risk of relapse is about 10% without either risk factor, 16% with one risk factor, and 32% with both risk factors.
Treatment options when surveillance is not chosen:
The surveillance-after-orchiectomy treatment option is associated with a cure rate that approaches 100%. Relapses requiring additional therapy occur in about 15% of patients who are treated with the surveillance treatment option. The surveillance strategy avoids the need for radiation or chemotherapy in most patients. However, some patients are uncomfortable with surveillance only and wish to minimize the risk of relapse. For such patients, one of the following options may be used; however, there is controversy about which strategy is preferred:
- Removal of the testicle via radical inguinal orchiectomy followed by radiation therapy is an approach that is associated with a 5-year relapse-free survival (RFS) rate of 95% to 96% and a 5-year disease-specific survival rate in excess of 99% in multiple large series and randomized controlled trials.[11-17]
One of the following two treatment fields is typically used: a para-aortic strip covering the retroperitoneal nodes or a dog-leg field that includes the ipsilateral iliac lymph nodes as well as the retroperitoneum. The dose ranges from 20 Gy to 26 Gy. Relapse rates and toxic effects were studied in a randomized comparison (MRC-TE10) of para-aortic radiation therapy alone versus para-aortic radiation therapy with an added ipsilateral iliac lymph node field.[13,18] Five-year RFS rates were virtually identical (96.1% for patients who were treated with the para-aortic strip vs. 96.2% for patients who were treated by a dog-leg field) as were overall survival (OS) rates (one death from seminoma occurred in the para-aortic radiation therapy arm). Pelvic RFS rates were 98.2% versus 100%; the 95% confidence interval (CI) for the difference in pelvic RFS rates was 0% to 3.7%. A statistically significant increase was observed in leukopenia and diarrhea associated with the ipsilateral iliac radiation therapy.
In a randomized trial (MRC-TE18), a radiation dose of 20 Gy over 10 daily fractions was clinically equivalent to 30 Gy over 15 fractions after a median follow-up of 7 years in both RFS and OS. Patients reported that lethargy and their ability to perform normal work were better in the lower-dose regimen.[14,18][Level of evidence: 1iiA]
Radiation therapy for clinical stage I testicular seminoma is no longer favored because of evidence that this treatment is associated with an increased risk of secondary malignancies and an increased risk of death from secondary malignancies. An analysis of data from the population-based Surveillance, Epidemiology, and End Results (SEER) registries in the United States between the years 1973 and 2001 indicated that among 7,179 men receiving radiation therapy for stage I seminoma, 246 had an increased risk of death from secondary cancers compared with the general population (standardized mortality ratio, 1.89; 95% CI, 1.67–2.14). An international study of more than 40,000 testis cancer survivors reported that among the 7,885 survivors who had been followed for 20 to 29 years, radiation therapy was associated with a doubling of the risk of secondary cancers (relative risk, 2.0; 95% CI, 1.8–2.3).
- Radical inguinal orchiectomy followed by either one or two doses of carboplatin adjuvant therapy.
In a large, randomized, controlled, noninferiority trial (MRC-TE19 [NCT00003014]), 1,477 men with stage I seminoma were randomly assigned to undergo para-aortic (or dog-leg field, if clinically indicated) radiation therapy or to receive a single dose of carboplatin (concentration-versus-time or area-under-the-curve [AUC] × 7) after radical inguinal orchiectomy study participants were followed up for a median of 6.5 years.[18,21] The RFS rate at 5 years was 94.7% in the carboplatin arm and 96.0% in the radiation therapy arm (1.3% difference; 90% CI, 0.7%–3.5%; hazard ratio [HR], 1.25 [nonsignificant trend in favor of radiation therapy]; 90% CI, 0.83–1.89). The one death from seminoma occurred in the radiation therapy arm. There was a reduced number of contralateral testicular germ cell tumors in the carboplatin arm: 2 versus 15 (HR, 0.22; 95% CI, 0.05–0.95; P = .03).[Level of evidence: 1iiA] In this trial, AUC dosing was based on radioisotope measurement of glomerular filtration rate; dosing based on calculations of creatinine clearance is not equivalent, has not been validated in this setting, and is discouraged.
Phase II studies, including several with more than 4 years median follow-up, have consistently reported lower relapse rates (0%–3.3%) when two doses of carboplatin were administered either 3 or 4 weeks apart and dosed either at 400 mg/m2 or at an AUC of 7.[3,4,22-26] Administration of two doses of carboplatin has never been compared with a single dose nor with radiation therapy in a randomized trial.
Stage I nonseminoma is highly curable (>99%). Orchiectomy alone will cure about 70% of patients, but the remaining 30% will relapse and require additional treatment. The relapses are highly curable, and postorchiectomy surveillance is a standard treatment option, but some physicians and patients prefer to reduce the risk of relapse by having the patient undergo either a retroperitoneal lymph node dissection (RPLND) or one or two cycles of chemotherapy. Each of these three approaches has unique advantages and disadvantages, and none has been shown to result in longer survival or superior quality of life.
Standard treatment options:
- Radical inguinal orchiectomy followed by a regular and frequent surveillance schedule.
Typically, patients are seen monthly during the first year, every 2 months during the second year, every 3 months during the third year, every 4 months during the fourth year, every 6 months during the fifth year, and annually for the subsequent 5 years.[27-29] At each visit, the history is reviewed, a physical examination is given, determination of serum markers are performed, and a chest x-ray is obtained (sometimes at alternating visits). An additional key aspect of surveillance involves abdominal or abdominopelvic CT scans, but the preferred frequency of such scans is controversial.
A randomized, controlled trial (MRC-TE08) compared a schedule that used only two scans at 3 months and 12 months with a schedule that used five scans at 3, 6, 9, 12, and 24 months. With over 400 randomly assigned patients and a median follow-up of 40 months, all relapsing patients had either good- or intermediate-risk disease, and there were no differences in the stage or extent of disease at relapse between the two arms. No deaths were reported. Nonetheless, some organizations recommend CT scans every 3 to 4 months during the first 3 years of follow-up and continuing but less-frequent CT scans thereafter. While this study would appear to indicate that scans at 3 and 12 months are adequate during the first year, longer follow-up will be needed to assess whether discontinuing scans after 12 months is safe.[Level of evidence: 1iiA] With regard to chest imaging, disease recurrence is rarely detected by chest x-ray alone, so chest x-ray may play little or no role in routine surveillance but is nonetheless included in the mainstream surveillance schedules.
The need for long-term follow-up has not been adequately investigated. Surveillance series with long follow-up times have reported that fewer than 1% of clinical stage I patients relapse after 5 years.[31,32] Late relapses often occur in the retroperitoneum when they do occur. Therefore, some schedules discontinue CT scans after 12 months, while others recommend at least annual scans for 10 years.
The option of a radical inguinal orchiectomy followed by a regular and frequent surveillance schedule should be considered only if:
- CT scan and serum markers are negative.
- The patient accepts the need for and commits to frequent surveillance visits. Children are adequately followed by alpha-fetoprotein serum markers, chest x-rays, and clinical examination.
- The physician accepts responsibility for seeing that a follow-up schedule is maintained as noted.
- Removal of the testicle through the groin followed (in adults) by RPLND.
A nerve-sparing RPLND that preserves ejaculation in virtually every patient has been described in clinical stage I patients and appears to be as effective as the standard RPLND.[34-36] Surgery should be followed by monthly determination of serum markers and chest x-rays for the first year and every-other-month determinations for the second year.
Men undergoing RPLND, who are found to have pathological stage I disease, have a roughly 10% risk of relapsing subsequently, whereas men with pathological stage II disease (i.e., those who are found to have lymph node metastases at RPLND) have as much as a 50% risk of relapse without further treatment. Two cycles of post-RPLND chemotherapy using either bleomycin, etoposide, and cisplatin (BEP) or etoposide plus cisplatin (EP) lowers the risk of relapse in men with pathological stage II disease to about 1%.[38,39] The vast majority of reported patients in studies of RPLND underwent the operation at a center of excellence with a urological surgeon who had performed hundreds of such operations. The ability of less-experienced urologists to achieve similar results is unknown.
In patients with pathologic stage I disease after RPLND, the presence of lymphatic or venous invasion or a predominance of embryonal carcinoma in the primary tumor appears to predict for relapse.[40-42] In a large, Testicular Cancer Intergroup Study, the relapse rate among men with pathological stage I disease was 19% in those with vascular invasion versus 6% in those without vascular invasion. One study reported that the relapse rate for men with pathological stage I disease was 21.2% (18 of 85 men relapsed), if their tumors were predominantly embryonal carcinoma and 29% if there was a predominance of embryonal carcinoma plus lymphovascular invasion versus 3% (5 of 141 men relapsed), if there was not a predominance of embryonal carcinoma.[40,41]
Among pathological stage II patients, the relapse rate was 32% among men with embryonal carcinoma-predominant tumors compared with15.6% in the other stage II patients. The risk of metastatic disease (i.e., either pathological stage II disease or relapsed pathological stage I disease) in men with tumors showing a predominance of embryonal carcinoma plus lymphovascular invasion was 62% compared with 16% in men with neither risk factor.
These data have shown that high-risk patients undergoing RPLND have a substantial risk of subsequently receiving chemotherapy. Data from one institution have shown that about half of men with stage I pure embryonal carcinoma undergoing RPLND will subsequently receive cisplatin-based chemotherapy.
Retroperitoneal dissection of lymph nodes is not helpful in the management of children, and potential morbidity of the surgery is not justified by the information obtained. In men who have undergone RPLND, chemotherapy is employed immediately on first evidence of recurrence.
- Adjuvant therapy consisting of one or two courses of BEP chemotherapy in patients with clinical stage I disease.
A randomized, controlled trial compared a single cycle of BEP chemotherapy to RPLND in 382 patients. The 2-year recurrence-free survival rates were 99.5% with chemotherapy versus 91.9% with RPLND (absolute difference = 7.6%; 95% CI, 3.1%–12.1%). There were no treatment-related or cancer-specific deaths in either arm of the study.
A Swedish and Norwegian study reported results of a risk-adapted therapy protocol in which patients with nonseminomas with lymphovascular invasion underwent postorchiectomy chemotherapy with one or two cycles of BEP chemotherapy, while those without lymphovascular invasion underwent either surveillance or a single cycle of BEP. The study included 745 patients and, with a median follow-up of 4.7 years and 2-year follow-up of 89% of patients, there were no deaths from testicular cancer, although one patient died of a stroke immediately after completing chemotherapy for relapsed disease. OS and cause-specific survival were 98.9% and 99.9%, respectively. Both of these studies were conducted at community-based hospitals and demonstrated that postorchiectomy chemotherapy could be delivered at a regional or national level without depending on centers of excellence.
Several phase II studies and case series reporting the results after two cycles of BEP in intermediate- or high-risk patients have identified relapse rates ranging from 0% to 4% (average = 2.4%). Fewer than 1% of patients in these series died of testicular cancer. While chemotherapy produces the lower relapse rate and a comparable disease-specific survival rate compared with RPLND or surveillance, it is unknown whether a brief course of chemotherapy results in late toxic effects or an increased risk of late relapse. Longer follow-up is awaited.
There is no consensus about the optimal management of men with stage I nonseminomas, but each of the three strategies above produces a disease-specific survival rate of about 99%. Some clinicians have advocated a risk-adapted approach such that low-risk patients undergo surveillance, while others undergo either RPLND or chemotherapy. The goal of this approach is to minimize the side effects of treatment, but risk-adapted therapy has never been demonstrated to result in better outcomes. Some experts prefer a surveillance strategy generally so as to minimize unnecessary treatment. Others prefer RPLND to obtain more accurate staging, to reduce the risk of needing chemotherapy (and, therefore, chemotherapy's side effects and toxicity) and to, theoretically, reduce the risk of late relapse. At the same time, many experts reject RPLND as insufficiently effective at lowering relapse rates and prefer chemotherapy. Surveillance and chemotherapy have been tested at the regional and national level with excellent results, however, the limited data concerning RPLND in the regional setting have shown higher than expected in-field relapse rates but no deaths.[44,45]
With regard to risk stratification, data suggest that relapse rates are higher in patients with histologic evidence of lymphatic or venous invasion or a predominance of embryonal carcinoma.[12,31,40,41,47] Tumors that consist of mature teratoma appear to have a lower relapse rate.Current Clinical Trials
Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with stage I malignant testicular germ cell tumor. The list of clinical trials can be further narrowed by location, drug, intervention, and other criteria.
General information about clinical trials is also available from the NCI Web site.References
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