Role of lymphangiography in staging testicular seminoma

Imaging of the lymphatic system: new horizons

The lymphatic system is a complex network of lymph vessels, lymphatic organs and lymph nodes. Traditionally, imaging of the lymphatic system has been based on conventional imaging methods like computed tomography (CT) and magnetic resonance imaging (MRI), whereby enlargement of lymph nodes is considered the primary diagnostic criterion for disease. This is particularly true in oncology, where nodal enlargement can be indicative of nodal metastases or lymphoma. CT and MRI on their own are, however, anatomical imaging methods. Newer imaging methods such as positron emission tomography (PET), dynamic contrast-enhanced MRI (DCE-MRI) and color Doppler ultrasound (CDUS) provide a functional assessment of node status. None of these techniques is capable of detecting flow within the lymphatics and, thus, several intra-lymphatic imaging methods have been developed. Direct lymphangiography is an all-but-extinct method of visualizing the lymphatic drainage from an extremity using oil-based iodine contrast agents. More recently, interstitially injected intra-lymphatic imaging, such as lymphoscintigraphy, has been used for lymphedema assessment and sentinel node detection. Nevertheless, radionuclide-based imaging has the disadvantage of poor resolution. This has lead to the development of novel systemic and interstitial imaging techniques which are minimally invasive and have the potential to provide both structural and functional information; this is a particular advantage for cancer imaging, where anatomical depiction alone often provides insufficient information. At present the respective role each modality plays remains to be determined. Indeed, multi-modal imaging may be more appropriate for certain lymphatic disorders. The field of lymphatic imaging is ever evolving, and technological advances, combined with the development of new contrast agents, continue to improve diagnostic accuracy.

Adjuvant radiation therapy for low stage testicular seminoma: Diagnosis and therapy in evolution

We performed a retrospective study to evaluate the clinical outcome of patients with early stage testicular seminoma who received adjuvant radiation therapy after orchiectomy over the past 15 years. During the 15 year period, 61 patients were treated with adjuvant radiation therapy for stages I, IIA, and IIB testicular seminoma. Patients received from 2,000 to 4,000 cGy delivered by a Cobalt machine and later by a linear accelerator. Our standard treatment protocol was modified in 13 patients: 7 secondary to abnormal lymphangiography (LAG) parameters and 6 due to abnormal computed tomography findings. We analyzed each patient's outcome for survival, recurrence, and complications. We then compared outcomes, looking for differing trends based on evolving evaluation or treatment techniques. The average follow-up is 75 months, with an overall survival rate of 93%. The cause specific survival is 100%. Four patients died from intercurrent diseases; at time of autopsy, one of these patients was noted to have a small focus of seminoma in a lateral inguinal node. He died from widely disseminated Hodgkin's disease. Three patients, including the aforementioned one, had recurrent disease outside of the radiation field, yielding a recurrence rate of 5%. No significant long term treatment complications were reported, although 24% of patients had one or more complications from LAG. Regardless the various changes in patient evaluation and radiation treatment techniques over the past 15 years, adjuvant radiation therapy remains effective in patients with early stage testicular seminoma.

Testicular seminoma: a failure analysis and literature review

PURPOSE

A retrospective analysis of 74 patients with pure seminoma, treated at the University of Florida between 1964 and 1989, was undertaken.

METHODS AND MATERIALS

All patients received megavoltage irradiation, with chemotherapy reserved for salvage. At 10 years, the probability of relapse-free survival was 91% for Stage I, 93% for Stage IIA, 83% for Stage IIB, and 75% for Stage III patients.

RESULTS

There were seven recurrences, none of which occurred in irradiated areas. Only two of seven patients (29%) with recurrence were salvaged.

CONCLUSION

A literature review revealed an increasing rate of mediastinal or supraclavicular recurrence, correlating with the size of the subdiaphragmatic disease, in Stage II patients who did not receive elective mediastinal irradiation. Recommendations are made regarding the role of elective mediastinal irradiation for Stage II disease. We conclude that patients with Stage I or II seminoma can have high cure rates when treated with radiotherapy alone. Patients with Stage III seminoma should be treated initially with cisplatin-based chemotherapy.

Indirect computed tomography lymphography of subdiaphragmatic lymph nodes using iodinated nanoparticles in normal dogs

RATIONALE AND OBJECTIVES

We evaluated the imaging characteristics of an iodinated particulate contrast agent for indirect computed tomography (CT) lymphography of normal subdiaphragmatic lymph nodes in dogs.

METHODS

Four milliliters of a 15% (wt/vol) iodinated nanoparticle suspension was injected into the gastric, colonic, rectal, or cervical submucosa, loose paraprostatic fascia, or metatarsal subcutaneous tissues in 10 healthy beagles. Endoscopic, CT, or ultrasound guidance was used when necessary to facilitate contrast agent delivery. CT and radiographic images were obtained prior to contrast administration and at 4 hr, 24 hr, and 7 days postcontrast injection. Postmortem examinations were then conducted.

RESULTS

CT images showed enhancement of regional lymph nodes draining the various injection sites. The mean attenuation of opacified nodes was 678 +/- 463 Hounsfield units 24 hr after injection and remained elevated 7 days later. Lymph node opacification on CT images correlated well with the node location observed on postmortem examinations.

CONCLUSION

Subdiaphragmatic lymph nodes can be effectively opacified using an iodinated nanoparticle contrast agent for indirect CT lymphography.

Has lymphography a role in early stage testicular germ cell tumours?

A retrospective study was performed of 183 newly diagnosed seminoma cases and 73 newly diagnosed non-seminomatous germ cell tumours (NSGCT) presenting from 1985 to 1989 to a tertiary referral cancer hospital. The purpose was to assess the contribution of bipedal lymphography (LG) to the management of these patients. As the main value of LG is in detecting small retroperitoneal lymph node (LN) metastases, analysis concentrated upon early stage disease, specifically N0 and N1a LN disease. Comparison between LG results, abdominopelvic computed tomography (APCT), final clinical stage and treatment outcome was performed. We found that with the LG and APCT criteria used (filling defects > 2 mm and LN diameter > 20 mm, respectively), LG was much more sensitive in disease detection. However, with modern techniques APCT can reliably detect disease 10 mm or greater. In addition, tumour marker status, primary tumour vascular invasion status and initial clinical examination were each more important in staging NSGCT disease than LG alone. Thus, LG is now rarely used in our institution but we will have to monitor our excellent survival data to confirm that this change in policy is warranted.

Iodinated nanoparticles for indirect computed tomography lymphography of the craniocervical and thoracic lymph nodes in normal dogs

RATIONALE AND OBJECTIVES

We evaluated the imaging characteristics of an interstitially or intraperitoneally delivered iodinated particulate contrast agent for computed tomography (CT) lymphography of the craniocervical and thoracic lymph nodes.

METHODS

We injected 2-4 ml of 15% wt/vol iodinated nanoparticle suspension subcutaneously, submucosally, or intraperitoneally in eight normal dogs. CT and plain radiographic images were obtained prior to contrast administration and 4 hr, 24 hr, and 7 days after injection. Correlation was made to detailed postmortem assessment.

RESULTS

CT images showed enhancement of regional nodes draining injection sites. Mean attenuation of opacified nodes was 313 +/- 297 (mean +/- standard deviation), 536 +/- 453, and 492 +/- 372 Hounsfield units at 4 hr, 24 hr, and 7 days postinjection, respectively. Lymph node opacification on CT images correlated well with node location found at postmortem.

CONCLUSION

Craniocervical and thoracic lymph nodes can be effectively opacified from interstitial or intraperitoneal delivery of this iodinated nanoparticulate contrast agent.

Post-orchiectomy radiotherapy for stages I and II testicular seminoma

PURPOSE

In 1984 the following changes were made in the management of testicular seminoma at The University of Texas M.D. Anderson Cancer Center: (1) abdominopelvic computerized tomography replaced the bipedal lymph-angiogram for evaluating retroperitoneal nodes; (2) elective mediastinal radiation was totally abandoned; (3) patients with abdominal adenopathy < 10 cm were classified as having Stage IIA disease. This report evaluates the impact of these management policy changes on disease outcome.

METHODS AND MATERIALS

Between 1960 and 1991, 350 patients with Stages I or II testicular seminoma received post-orchiectomy radiation. The 241 patients treated prior to 1984 constitute our old series, and the 109 patients treated since then are our new series. The outcomes in the new series were compared to those in the old series.

RESULTS

The distribution of patients by stage was Stage I, 282 (old series, 190; new series, 92); Stage IIA, 55 (old series, 39; new series, 16); Stage IIB, 13 (old series, 12; new series, 1). The freedom-from-relapse at 5 years correlated with stage: Stage I, 97%; Stage IIA, 87%; Stage IIB, 69%. Elevated post-orchiectomy chorionic gonadotropin levels or involvement of the spermatic cord were adverse for disease relapse in Stage I but not Stage II disease. Patients with Stage I disease fared extremely well in both series (freedom-from-relapse 97%); the outcome for patients with Stage IIA was significantly worse in the new series (5-year freedom-from-relapse 73% vs. 92%) because of a 20% actuarial incidence of apparently solitary left supraclavicular nodal relapse. Although elective mediastinal radiation in the old series prevented this failure pattern, such treatment appeared to significantly decrease the survival of patients older than 40 years.

CONCLUSIONS

(1) Abdominopelvic computerized tomography scanning is adequate for the evaluation of abdominal lymph nodes in patients with seminoma; (2) Post-orchiectomy radiation to the para-aortic and ipsilateral hemipelvic regions remains the treatment of choice for patients with Stage I disease; (3) Patients with Stage IIA disease experience a 20% relapse rate especially in the left supraclavicular fossa and we recommend elective radiation to this site delivered concomitantly with para-aortic irradiation.