3. Testicular Cancer
Testicular tumors are classified as either semino-mas or nonseminomas. The initial treatment for all tumors is radical (inguinal) orchiectomy. Sub-sequent management depends on tumor histology. Nonseminomas include embryonal teratoma, cho-riocarcinoma, and mixed tumors. Retroperitoneal lymph node dissection (RPLND) plays a major role in the staging and management of patients with nonseminomatous germ cell tumors. Low-stage dis-ease is managed with RPLND or in some instances by surveillance. High-stage disease is usually treated with chemotherapy followed by RPLND.
In contrast to nonseminomas, seminomas are very radiosensitive tumors that are primarily treated with retroperitoneal radiotherapy. Chemotherapy is used for patients who relapse after radiation. Patients with large bulky seminomas or those with increased α-fetoprotein levels (usually associated with nonseminomas) are treated primarily with che-motherapy. Chemotherapeutic agents commonly include cisplatin, vincristine, vinblastine, cyclo-phosphamide, dactinomycin, bleomycin, and etopo-side. RPLND is usually undertaken for patients with residual tumor after chemotherapy.
Patients undergoing RPLND for testicular can-cer are typically young (15–35 years old) but are at increased risk for morbidity from the residual effects of preoperative chemotherapy and radiation therapy. In addition to bone marrow suppression, specific organ toxicity may be encountered such as renal impairment following cisplatin, pulmonary fibrosis following bleomycin, and neuropathy fol-lowing vincristine.
Inguinal orchiectomy can be carried out with regional or general anesthesia. Anesthetic manage-ment may be complicated by reflex bradycardia from traction on the spermatic cord.
The retroperitoneum is usually accessed through a midline incision, but regardless of the surgical approach, all lymphatic tissue between the ureters from the renal vessels to the iliac bifurcation is removed. With the standard RPLND, all sympa-thetic fibers are disrupted, resulting in loss of nor-mal ejaculation and infertility. A modified technique that may help preserve fertility limits the dissection below the inferior mesenteric artery to include lym-phatic tissue only on the ipsilateral side of the tes-ticular tumor. Patients receiving bleomycin preoperatively may be particularly at risk for oxygen toxicity and fluid overload, and for developing pulmonary insufficiency or acute respiratory distress syn-drome postoperatively. Excessive intravenous flui administration may be contributory. Anesthetic management should include use of the lowest inspired concentration of oxygen compatible with oxygen saturation above 90%. Positive end-expira-tory pressure (5–10 cm H2O) may be helpful in opti-mizing oxygenation.
Evaporative and redistributive fluid losses (“third spacing”) with open RPLND can be consid-erable as a result of the large wound and the exten-sive surgical dissection. Fluid replacement should be sufficient to maintain urinary output greater than 0.5 mL/kg/h; the combined use of both colloid and crystalloid solutions in a ratio of 1:2 or 1:3 may be more effective in preserving urinary output than crystalloid alone. Retraction of the inferior vena cava during surgery often results in transient arterial hypotension.
The postoperative pain associated with open RPLND incisions is severe, and aggressive postop-erative analgesia is helpful. Continuous epidural analgesia, extended-release epidural morphine, or intrathecal morphine (or hydromorphone) should be considered. Because ligation of intercostal arter-ies during left-sided dissections has rarely resulted in paraplegia, it may be prudent to document nor-mal motor function postoperatively prior to insti-tution of epidural analgesia. The arteria radicularis magna (artery of Adamkiewicz), which is supplied by these vessels and is responsible for most of the arterial blood to the lower half of the spinal cord, arises on the left side in most individuals. It should be noted that unilateral sympathectomy following modified RPLND usually results in the ipsilateral leg being warmer than the contralateral one. Patients who have undergone RPLND frequently complain of severe bladder spasm pain in the postanesthesia care unit and postoperatively.
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