Affiliation of authors: Breast Unit, Istituto Nazionale per lo Studio e la Cura dei Tumori, Milan, Italy.
Correspondence to: Marco Greco, M.D., Breast Unit, Istituto Nazionale per lo Studio e la Cura dei Tumori, Via Venezian 1, 20133, Milan, Italy (e-mail: marco.greco{at}istitutotumori.mi.it).
The aim of our study (1) was to evaluate the role of positron emission tomography (PET) in lymph node staging of breast cancer as an alternative to surgical staging. The sensitivity of PET would be reduced if compared with serial sectioning (i.e., each section at a thickness of 250 µm) followed by systematic staining by immunohistochemistry. Even such a choice, however, can be considered arbitrary and still inadequate to evaluate the real condition of lymph nodes. In fact, because the diameter of the neoplastic cell can be less than 10 µm, the ideal distance between the two sections should be shorter than 10 µm to be sure of detecting any individual metastasized tumor cell. More sophisticated and accurate methods of lymph node evaluation (i.e., reverse transcription-coupled polymerase chain reaction) (2) have been described with the aim of reducing the rate of false-negative sentinel nodes. However, it is impractical to routinely use these procedures for lymph node staging even for a sentinel node. At this point, what is really crucial is to determine the cutoff of the lymph node tumor load that may used to compare an alternative procedure with the traditional axillary dissection.
Other methods reported for validation of the sentinel node procedure, in which a more accurate assessment was used for the sentinel node than for other axillary lymph nodes, lead to a bias in the evaluation of lymph node metastases. In our study, we chose the histopathologic method commonly used in clinical practice and uniformly applied to every lymph node removed.
Besides the fact that prognostic importance of micrometastases has yet to be defined completely, we must now consider the value of axillary lymph node staging with respect to treatment. Since 25% of lymph node-negative breast cancers have a poor prognosis, several authors look for a more accurate histologic method to detect lymph node metastases and convert a variable fraction of lymph node-negative breast cancers into lymph node-positive ones. Thus, it is reasonable to predict that an increased rate of lymph node-positive breast cancers will have a good prognosis, altering a prognostic stratification, which is the aim of the staging. It is also known that lymph node-positive breast cancers with favorable morphologic and biologic tumor variables show a better prognosis than lymph node-negative ones associated with adverse factors (3).
When lymph node staging is integrated with several biomolecular variables of tumors in the stratification of the risk (4,5), lymph node information (not lost with PET) influences the adjuvant treatment only in 6% of patients (6). Therefore, we believe that the lack of identification of lymph node micrometastases does not lead to an inadequate treatment. Even avoiding axillary dissection, it does not seem to lead to a suboptimal treatment (7) if the decision is supported by an adequate evaluation of the biology of the tumor.
Thus, in our institute, a randomized clinical trial is ongoing with the aim of redefining the role of lymph node staging in the multimodal treatment of stage T1N0 breast cancer. The study arm does not include any lymph node staging or any primary lymph node treatment, and the choice of a systemic adjuvant treatment is determined through more complex biologic evaluation of the primary tumor.
REFERENCES
1
Greco M, Crippa F, Agresti R, Seregni E, Gerali A, Giovanazzi R, et al. Axillary lymph node staging in breast cancer by 2-fluoro-2-deoxy-D-glucosepositron emission tomography: clinical evaluation and alternative management. J Natl Cancer Inst 2001;93:6305.
2 Bostick PJ, Huynh KT, Sarantou T, Turner RR, Qi K, Giuliano AE, et al. Detection of metastases in sentinel lymph nodes of breast cancer patients by multiple-marker RTPCR. Int J Cancer 1998;79:64551.[Medline]
3 Menard S, Bufalino R, Rilke F, Cascinelli N, Veronesi U, Colnaghi MI. Prognosis based on primary breast carcinoma instead of pathological nodal status. Br J Cancer 1994;70:70912.[Medline]
4
Goldhirsch A, Glick JH, Gelber RD, Seen HJ. Meeting highlights: International Consensus Panel on the Treatment of Primary Breast Cancer. J Natl Cancer Inst 1998;90:16018.
5
Eifel P, Axelson JA, Costa J, Crowley J, Curran WJ Jr, Deshler A, et al. National Institutes of Health Consensus Development Conference Statement: adjuvant therapy for breast cancer, November 13, 2000. J Natl Cancer Inst 2001;93:97989.
6 Greco M, Gennaro M, Valagussa P, Agresti R, Ferraris C, Ferrari B, et al. Impact of nodal status on indication for adjuvant treatment in clinically node negative breast cancer. Istituto Nazionale per lo Studio e las Cura dei Tumori. Ann Oncol 2000;11:113740.[Abstract]
7 Greco M, Agresti R, Cascinelli N, Casalini P, Giovanazzi R, Maucione A, et al. Breast cancer patients treated without axillary surgery: clinical implications and biologic analysis. Ann Surg 2000;232:17.[Medline]
![]() |
||||
|
Oxford University Press Privacy Policy and Legal Statement |