Management of clinical stage 1 disease
MANAGEMENT OF CLINICAL STAGE I DISEASE
The management of clinical stage I seminoma has not changed significantly in the last 20 years. Radiation therapy remains the treatment of choice. The ipsilateral hemiscrotum does not require therapy unless gross tumor spillage has taken place. Conventional fractionation for clinical stage I disease is 150 to 180 cGy/d for five sessions per week using high-energy linear accelerator beams to a total dose of 2500 to 3000 cGy. Elective, prophylactic radiation therapy to the mediastinum is contraindicated. The contralateral testis should be shielded during treatment. Proper shielding will result in an exposure 1% or less of the total dose. The relapse rate within the irradiated portal after adequate radiation therapy is negligible. The systemic relapse rate, usually presenting as a supraclavicular mass, ranges from 2% to 9%, and the death rate is under 2%. CT scanning of the abdomen and pelvis is required and has replaced intravenous pyelography. LAG may have two purposes. Small nodal metastases that distort architecture but do not increase nodal size may be identified, and the field size may be smaller than those planned on the basis of CT alone. The smaller field may reduce the long-term effects of abdominal radiotherapy. For left-side, primary testicular tumors, the left renal hilum must be encompassed. Treatment of pelvic lymph nodes is sometimes required for T4 primary tumors or for scrotal violations with tumor spillage. An involved spermatic cord margin at the internal ring may also require field extension.
Although the dose of radiation therapy is low and the cure rate exceptionally high, long-term sequelae include the potential for an increased incidence of gastrointestinal neoplasms (see later). As a consequence, studies have been performed investigating observation as the only management after orchiectomy, to be followed by chemotherapy at relapse. The relapse rate is approximately 15%, but the median time to relapse is about 12 months, longer than that observed for nonseminomatous GCT. Moreover, relapses have occurred at intervals more than 5 years from diagnosis, implying that abdominal CT scanning to detect late relapses must occur indefinitely in patients with seminoma. Therefore, in the United States, observation for clinical stage I seminoma is not considered routine.
NONSEMINOMATOUS GERM CELL TUMORS
Nonseminomatous GCT is relatively radioresistant. Therefore, radiation therapy plays no role in its initial management. If a patient has clinical stage I disease at the conclusion of initial staging, three management options remain, the choice of which depends on specific histologic features and status of serum tumor marker concentrations.
Retroperitoneal Lymph Node Dissection
Because of predictable lymphatic metastatic spread, the conventional approach to patients with clinical stage I nonseminomatous GCT has been the modified, bilateral RPLND. Adequate exposure for RPLND can be achieved through either a transthoracic or a transabdominal approach. The standard bilateral infrahilar RPLND template, which remains the standard against which therapeutic alternatives are judged, includes the paracaval, interaortocaval, preaortic, paraaortic, and common iliac lymph nodes bilaterally.
Despite refinement of radiologic imaging, 15% to 40% of patients are clinically understaged. Retroperitoneal metastases will be found in about 30% of patients judged preoperatively to be clinical stage I. Retroperitoneal relapse will occur in about 20% to 25% of patients on clinical stage I surveillance protocols, and teratoma or viable cancer will be found pathologically in 20% of patients with a normal postchemotherapy CT scan.
Infield recurrence is rare after a properly performed RPLND, which is a curative procedure in the majority of patients with N1 disease, with relapse rates less than 35% without adjuvant chemotherapy and essentially no relapses for higher stage nodal disease followed by two cycles of cisplatin-based chemotherapy. Surgical mortality is less than 1%. Major complications are unusual but can include pancreatitis, renal vascular or ureteral injuries, chylous ascites, aortic wall necrosis, bowel obstruction, pulmonary emboli, hemorrhage, and wound dehiscence. Minor complications include lymphocele, atelectasis, wound infection, and prolonged ileus.
Most patients undergoing bilateral RPLND experience retrograde ejaculation and subsequent infertility. An improved understanding of the neuroanatomy of seminal emission and ejaculation, the pattern of retroperitoneal metastasis for right- and left-sided tumors, and surgical mapping studies led to modification of infrahilar surgical boundaries and techniques. Two approaches have been used: (1) formal dissection and preservation of sympathetic fibers, and (2) modified template that avoids (but does not specifically identify) sympathetic fibers.