The role of lymphoscintigraphy in the management of the patient with breast cancer.

INTRODUCTION: Regional nodal status is the most powerful predictor of recurrence and survival in women with breast cancer. Lymphatic mapping and sentinel lymph node (SLN) biopsy have been found to accurately predict the regional nodal status. Preoperative lymphoscintigraphy has been used in melanoma patients to identify the basins at risk for metastases when primary sites are located in watershed areas of the body. This study was performed to define the role of lymphoscintigraphy for axillary nodal staging in women with breast cancer. Specifically, can preoperative lymphoscintigraphy define a population of women with breast cancer who have multidirectional drainage or who do not drain to the axilla and need no axillary dissection? METHODS: 516 patients with invasive breast cancer were accrued in a national breast lymphatic mapping trial sponsored by the U.S. Department of Defense. Preoperative lymphoscintigraphy images were produced using filtered technetium-99 sulfur colloid. Lymphatic drainage to axillary and internal mammary sites was noted. RESULTS: Drainage to an axillary SLN was found in 335 (65%) patients, and internal mammary or extra-axillary drainage was noted in 52 (10%) patients. By using sensitive hand-held probes and vital blue dye intraoperatively, the overall success rate of finding an axillary SLN was 85%. Of the 335 patients who had an axillary SLN identified with imaging, all had successful SLN biopsy procedures. Although no SLNs could be imaged in 181 patients, 153 (85%) of these patients had an axillary SLN identified with intraoperative mapping. For 28 patients in which lymphoscintigraphy was negative and intraoperative mapping was unsuccessful, complete axillary node dissection was performed, and 13 (46%) of these patients were found to have metastatic disease in the basin. CONCLUSIONS: Preoperative lymphoscintigraphy can identify those women with primary breast cancers who have extra-axillary regional basin drainage such as internal mammary. The ability to image an axillary SLN was associated with a high success rate of being able to find the node intraoperatively with a combination mapping technique. In a high percentage of patients with negative lymphoscintigraphy, the SLN was identified with more sensitive hand-held probes. Therefore, patients who have a negative preoperative lymphoscintigraphy and intraoperatively are found to have no "hot" spot in the axilla with the hand-held probe still need an axillary node dissection, because 46% of these patients contain metastatic disease in the axilla.

The clinical relevance of molecular staging for melanoma.

The presence of metastatic disease in the regional nodal basin is the most important prognostic indicator for patients with malignant melanoma. The metastatic status of the sentinel lymph node (SLN), defined as the first node in the basin to drain a primary tumor, has been shown to represent that of the entire basin. Since routine histologic examination of lymph nodes often underestimates the presence of micrometastatic disease, a more sensitive assay for detecting tumor cells is needed. We have previously shown that a molecular assay based on the reverse transcriptase polymerase chain reaction (RT-PCR) was able to define a population of patients at higher risk for both recurrence and death, compared with routine H&E histology. Recently, we have compared "molecular staging" of patients by RT-PCR with conventional S-100 immunohistochemistry (IHC) staining of the SLNs. In these studies, SLN specimens were bivaled, and half of each specimen was examined by routine histology, including both H&E and S-100 IHC. The other half of each specimen was analyzed by a nested RT-PCR assay. H&E histology alone detected metastatic disease in 36 of 233 (16%) patients tested. Serial sectioning and IHC detected micrometastatic disease in another 16 patients, thus increasing the proportion of patients with nodal disease to 22%. RT-PCR detected micrometastatic disease in 114 of 181 patients who were negative by conventional methods, further increasing the proportion of patients with evidence of nodal disease to 70% overall. The clinical significance of these findings is still uncertain. The value of additional therapy (including elective lymph node dissection and interferon therapy) for patients who are positive only by the molecular method is currently being investigated by the national multi-center Sunbelt Melanoma Trial.

Clinical relevance of molecular staging for melanoma: comparison of RT-PCR and immunohistochemistry staining in sentinel lymph nodes of patients with melanoma.

OBJECTIVE: To determine the clinical significance of a molecular assay based on the reverse transcriptase polymerase chain reaction (RT-PCR) for the presence of micrometastatic melanoma cells in sentinel lymph nodes (SLNs). SUMMARY BACKGROUND DATA: Routine histologic examination of lymph nodes often underestimates the presence of micrometastatic disease. The authors have previously shown that an RT-PCR assay designed to detect melanocyte-specific expression of the tyrosinase gene could be used to define a population of patients at higher risk for both recurrence and death compared with routine hematoxylin and eosin (H&E) histology. In this study, the authors used the tyrosinase RT-PCR assay in a patient population examined by a more detailed histologic analysis, including S-100 immunohistochemistry. METHODS: Patients underwent lymphatic mapping and SLN biopsy. SLN specimens were bivalved, and half of each specimen was serially sectioned and examined by routine H&E histology and S-100 immunohistochemistry. The other half of each specimen was analyzed by a nested RT-PCR assay. RESULTS: Hematoxylin and eosin histology detected metastatic disease in 36 (16%) of the 233 patients tested. S-100 immunohistochemistry detected micrometastatic disease in another 16 patients, and 114 (63%) of 181 patients with histology-negative nodes had positive findings on RT-PCR. There were significant differences between PCR-positive and PCR-negative patient groups in Breslow thickness, Clark level, and the presence of ulceration of the primary tumor, factors that have been shown to correlate with recurrence and survival. CONCLUSIONS: These results suggest that RT-PCR can increase the sensitivity of detection of metastatic melanoma cells in SLNs over the current standard methods, including H&E histology and S-100 immunohistochemistry. Further long-term follow-up is needed to detect actual differences in recurrence and overall survival.

Molecular staging for melanoma and breast cancer.

Despite increased sensitivity of PCR techniques, routine H&E histology and, in some cases, immunohistochemistry remain the gold standards for the detection of micrometastatic disease. Highly sensitive and specific molecular assays such as RT-PCR provide an ideal way to detect micrometastatic disease in tissues or blood at risk for metastases. RT-PCR has been shown to increase detection of micrometastases, especially in patients with breast cancer and melanoma. These assays have the potential to provide valuable tumor staging and progression information and thus determine the need for further surgery, adjuvant chemotherapy, and antigen-specific immunotherapy. As investigators gain more experience using molecular assays, the results of these assays will be more likely to guide clinical staging and decision making.

Historical perspectives and future applications.

Lymphatic Mapping and sentinel lymph node biopsy are developing into a new field of minimally invasive surgery. These procedures were brought about by the necessity to better stage patients while minimalizing morbidity. Their application is reaching several aspects of surgery and becoming a major foundation in the armamentarium of the general surgeon.

Molecular staging of malignant melanoma: correlation with clinical outcome.

CONTEXT: For most solid tumors, the metastatic status of regional lymph nodes is the strongest predictor of relapse and survival. However, routine pathological examination of lymph nodes may underestimate the number of patients with melanoma who have nodal metastases. OBJECTIVE: To determine the clinical significance of a highly sensitive molecular assay for occult nodal metastases for the staging of patients with melanoma. DESIGN: A prospective cohort study of consecutive patients in which lymphatic mapping and sentinel lymph node (SLN) biopsy were performed on 114 melanoma patients with clinical stage I and stage II disease. The SLNs were bivalved, and half of each specimen was submitted for routine pathological examination. The other half was submitted for molecular detection of submicroscopic metastases using a reverse transcriptase-polymerase chain reaction (RT-PCR) assay for tyrosinase messenger RNA as a marker for the presence of melanoma cells. Patient follow-up averaged 28 months. SETTING: A major university-based melanoma referral center at a National Cancer Institute-designated cancer center. PATIENTS: A total of 114 patients with newly diagnosed cutaneous malignant melanoma who were at risk for regional nodal metastases. MAIN OUTCOME MEASURE: Melanoma recurrence and overall survival. RESULTS: Twenty-three patients (20%) had pathologically positive SLNs, and all of these patients were also RT-PCR positive. Of the 91 pathologically negative patients, 44 were RT-PCR negative and 47 were RT-PCR positive. There was a recurrence rate among 14 (61%) of the 23 patients who were both pathologically and RT-PCR positive and a recurrence rate among 1 (2%) of 44 patients who were both pathologically and RT-PCR negative. For patients who were upstaged by the molecular assay (pathologically negative, RT-PCR positive), there was a recurrence rate among 6 (13%) of 47 patients. The differences in recurrence rates and overall survival between the pathologically negative, RT-PCR-negative and pathologically negative, RT-PCR-positive patient groups were statistically significant (P= .02 for disease-free survival and for overall survival). In both univariate and multivariate regression analyses, the histological and RT-PCR status of the SLNs were the best predictors of disease-free survival. CONCLUSIONS: The use of an RT-PCR assay for detection of submicroscopic melanoma metastases in SLNs improved the prediction of melanoma recurrence and overall survival over routine pathological examination.

delta 9-Tetrahydrocannabinol (THC) modulates IL-1 bioactivity in human monocyte/macrophage cell lines.

We have previously observed that delta 9-tetrahydrocannabinol (THC), the major psychoactive component of marijuana, increased supernatant interleukin-1 (IL-1) bioactivity in cultures of mouse resident peritoneal macrophages stimulated with lipopolysaccharide (LPS). In this study, experiments were performed to determine whether THC treatment similarly affected phagocytes of human origin. The results showed that THC increased the levels of supernatant IL-1 bioactivity of two human monocytic cell lines, but only if the cells were differentiated with phorbol myristate acetate. Undifferentiated cells displayed decreased IL-1 bioactivity in response to THC. However, under conditions in which THC augmented supernatant IL-1 bioactivity from THP-1 cells, ELISA studies showed that the levels of IL-1 alpha and IL-1 beta were unchanged and decreased, respectively. Furthermore, supernatant interleukin-6 (IL-6) levels were decreased, but tumor necrosis factor (TNF-alpha) levels were increased by THC treatment. These results show that THC treatment modulates cytokine production and/or release by mouse and human macrophages and the drug effects on IL-1-like bioactivity in the supernatants of the human THP-1 cells are due to increased levels of other cytokines, such as TNF-alpha, rather than IL-1 itself.