Sentinel lymph node as a new marker for therapeutic planning in breast cancer patients.

BACKGROUND AND OBJECTIVES: Literature review suggests that the sentinel lymph node (sN) represents a reliable predictor of axillary lymph node status in breast cancer patients; however, some important issues, such as the optimisation of the technique for the intraoperative identification of the sN, the role of intraoperative frozen section examination of the sN, and the clinical implications of sN metastasis as regards the surgical management of the axilla, still require further confirmation. The authors aimed (1) to assess the feasibility of sN identification with a combined approach (vital blue dye lymphatic mapping and radioguided surgery, RGS) and the specific contribution of either techniques to the detection of the sN, (2) to determine the accuracy and usefulness of intraoperative frozen section examination of the sN in order to perform a one-stage surgical procedure, and (3) to define how the sN might modulate the therapeutic planning in different stages of disease. MATERIALS AND METHODS: From October 1997 to June 2001, 334 patients with early-stage (T(1-2) N(0) M(0)) invasive mammary carcinoma underwent sN biopsy; the average age of patients was 61.5 years (range, 39-75 years). In a subset of 153 patients, both vital blue dye (Patent Blue-V) lymphatic mapping and RGS were used to identify the sN, and the relative contribution of each of the two techniques was assessed. RESULTS: In the whole group, the sN was identified in 326 of 334 patients (97.6%), and 105 of 326 patients (37.3%) had positive axillary lymph nodes (pN+). In 9 of 105 pN+ patients, the definitive histologic examination of the sN did not show metastases but these were detected in non-sN, thus giving an 8.6% false-negative rate, a negative predictive value of 94.5% (156/165), and an accuracy of 96.5% (252/261). As regards the specific contribution of the two different techniques used in the identification of the sN, the detection rate was 73.8% (113/153) with Patent Blue-V alone, 94.1% (144/153) with RGS alone, and 98.7% (151/153) with Patent Blue-V combined with RGS (P < 0.001). Noteworthy, whenever the sN was identified, the prediction of axillary lymph node status was remarkably similar (93-95% sensitivity; 100% specificity; 95-97% negative predictive value, and 97-98% accuracy) whichever of the three procedures was adopted (Patent Blue-V alone, RGS alone, or combined Patent Blue-V and RGS). Intraoperative frozen section examination was performed in 261 patients, who had at least one sN identified, out of 267 patients who underwent complete axillary dissection; 170 patients had histologically negative sN (i.o. sN-) and 91 patients histologically positive sN (i.o. sN+). All 91 i.o. sN+ were confirmed by definitive histology, whereas in 14 of 170 i.o. sN- patients (8.2%) metastases were detected at definitive histology. As regards the correlation between the size of sN metastasis, the primary tumour size, and the status of non-sN in the axilla, micrometastases were detected at final histology in 23 patients and macrometastases in 82 patients. When only micrometastases were detected, the sN was the exclusive site of nodal metastasis in 20 of 23 patients (86.9%) while in 3 patients with tumour size larger than 10 mm micrometastases were detected also in non-sN. Macrometastases were never detected in pT(1a) breast cancer patients; the sN was the exclusive site of these metastases in 30 patients (36.6%), while in 52 patients (63.4%) there were metastases both in sN and non-sN. CONCLUSIONS: Sentinel lymphadenectomy can better be accomplished when both procedures (lymphatic mapping with vital blue dye and RGS) are used, because of the significantly higher sN detection rate, although the prediction of axillary lymph node status remains remarkably similar whichever method is used. The intraoperative frozen section examination proved to be rather accurate in predicting the actual pathologic status of the sN, with a negative predictive value of 91.8%; in 35% of patients it allowed sN biopsy and axillary dissection to be performed in a one-stage surgical procedure. Finally, specific clinical and histopathologic features of the primary tumour and sN might be used to tailor the loco-regional and systemic treatment in different clinical settings, such as in ductal carcinoma in-situ (DCIS), early-stage invasive breast cancer, and patients with large breast cancer undergoing neo-adjuvant CT for breast-saving surgery as well as elderly patients with operable breast cancer.

Sentinel lymph node biopsy in patients with Stage I/II melanoma: Clinical experience and literature review.

BACKGROUND: The sentinel lymph node (sN) represents one of the most powerful predictors of the outcome of patients with Stages I and II cutaneous melanoma, and may be relevant for the therapeutic planning of early-stage melanoma patients. Since adopting the technique of lymphatic mapping with vital blue dye (Patent Blue-V) in July 1993, we have periodically up-dated the methodology and revised our results in order to define the contribution of radio-guided surgery (RGS) to the detection of the sN as well as the role of intraoperative frozen section examination of the sN. MATERIALS AND METHODS: Between July 1993 and December 1997, 180 patients with clinically node-negative primary cutaneous melanoma (Stages I-II) underwent sN biopsy followed by "selective lymph node dissection" (SLND) whenever sN metastasis was detected. Presently, complete data are available in 165 patients who were divided into two consecutive subsets of 39 and 126 patients, based on the technique for the identification of the sN: Patent Blue-V only or Patent Blue-V associated to RGS. Moreover, in this second subset of patients intraoperative frozen section findings were compared with definitive pathologic examination. RESULTS: As regards the first subset of 39 patients (17 males and 22 females; mean age 51.3 years), the sN was identified in 35 patients (89.7%); 8 patients (22.8%) were found to have metastatic melanoma cells in their sN, and they all underwent SLND of the affected basin. As regards the second set of 126 patients (54 males and 72 females; mean age 53.5 years), the sN was detected in every case by means of the combined technique (Patent Blue-V and RGS): in 4 of 126 patients (3.2%), the sN was detected by means of RGS only whereas in no patient was the sN detected by Patent Blue-V only. Frozen section examination was performed in 123 of 126 patients who had sN detection by Patent Blue-V and RGS, and the intraoperative examination had a sensitivity of 66.6% (22 of 33), specificity of 100% (90 of 90), negative predictive value of 89.1% (90 of 101), and accuracy of 91% (112 of 123). The benefit of frozen section examination in avoiding a two-stage procedure was 17.9% (22 of 123 patients). In patients with thicker lesions (pT(3)-pT(4)), the sensitivity and the benefit of intraoperative examination were 76% (19 of 25) and 32% (19 of 59 patients), respectively. CONCLUSIONS: Sentinel node lymphadenectomy can be better accomplished when both procedures (lymphatic mapping with Patent Blue-V and RGS) are used because the two methods look quite complementary. In fact, the use of the radiocolloid mapping allows to detect a hot spot in the regional basin prior to making the skin incision in order to perform a minimal invasive access, and it may also more accurately differentiate the true sN from a secondary echelon node (non-sN). The use of frozen section examination should be restricted to patients with pT(3)-pT(4) primary melanoma, due to the higher sensitivity and benefit in terms of avoiding a two-stage operative procedure.

Expression and localization of mutant p16 proteins in melanocytic lesions from familial melanoma patients.

Little is known about the correlation between the loss of p16 expression and tumor progression in familial melanoma; no systematic study has been conducted on p16 expression in melanocytic tumors from patients carrying germline CDKN2A mutations. We analyzed 98 early primary lesions from familial patients, previously tested for germline CDKN2A status, by quantitative immunohistochemistry using 3 p16 antibodies. We found that p16 expression was inversely correlated with tumor progression and was significantly lower in melanomas, including in situ lesions, than in nevi. Of other features analyzed, tumor thickness showed the most significant correlation with p16 levels. Lesions from mutation-negative patients displayed combined nuclear and cytoplasmic staining. However, some mutation-positive lesions (ie, G101W, 113insR, M53I, R24P, and 33ins24), including benign nevi, showed nuclear mislocalization, confirming previous studies suggesting that subcellular distribution indicates functional impairment of p16.

Trilucent breast implants: five years' experience from an Italian perspective.

In June 2000 the Medical Devices Agency (MDA) issued a Hazard Notice recommending the explantation of Trilucent breast implants (TBP) as a precautionary measure. Following that recommendation, we reviewed our series of 52 patients (71 implants) operated on from 1994 to 1998 to recall and advise those still harboring TBP. We have analyzed all the recorded adverse events in our setting before June 2000 to estimate the adverse reaction frequency and their time relation (review series). We have also recorded the rate of preoperative symptoms and postoperative findings in 23 patients (29 implants) who underwent explantation after the MDA recommendation (explantation series). In addition, some histologic observations have been made. The rates of significant capsular contracture (Baker 3-4) and explantations were estimated using the Kaplan-Meier method of survival analysis, and the rates of wrinkling and palpability were compared at 1 and 5 years of follow-up. Overall, the rate of grade 3-4 capsular contracture was approximately 45% at 6 years of follow-up with no statistically significant difference among the reconstruction and augmentation groups. The analysis of survival curves showed an overall rate of approximately 55% of explantations at 6 years. Preoperatively, capsular contracture and volume modifications were the most frequent findings in the explantation series. Postoperatively, most implants opposed inadequate resistance to the operative stress and ruptured, showing a creamy content. Free oil has never been found in tissue surrounding the periprosthetic capsule. In conclusion, it appears that the TBP-claimed advantages over other available implants seem to be inconsistent and the MDA advice appropriate. The problems related to these implants have had a great impact on public opinion in Europe and have contributed to the implementation of the conformity assessment procedures to be followed for medical devices: on the 4th February 2003 breast implants were in fact reclassified as class 3 products, in order to provide the best guarantee for health protection. The publication of a communication by the European Parliament in November 2001 gives us hope for the future.

Nuclear matrix proteins changes in cancerous prostate tissues and their prognostic value in clinically localized prostate cancer.

BACKGROUND: After the discovery that nuclear matrix (NM) directs the spatial organization of DNA transcription and replication, there has been an increasing interest in studying NM changes associated with malignant transformation and their potential usefulness in the clinical setting. METHODS: High-resolution two-dimensional gel electrophoresis was used to analyze the NM proteins (NMP) of specimens of prostate cancer tissue obtained from the prostates of 75 patients undergoing retropubic prostatectomy. RESULTS: Nine NMP with different molecular weights and isoelectric points have been identified. They were expressed differently by prostate cancer tissues. An increasing trend toward the expression of such proteins like NMP 6-8 was evident with increasing tumor stage and dedifferentiation. NMP 6-8 were also significantly correlated with the risk of biochemical progression. However, Gleason score was the only significant discriminant in this regard in multiparametric models. CONCLUSIONS: This study confirms that prostate cancer progression is related to profound changes in NMP expression patterns. However, due to the complexity of the methods required to define these latter, the clinical relevance of NMP appears to be still limited.

A decision support system to detect morphologic changes of chromatin arrangement in normal-appearing cells.

Several studies have described malignancy-associated changes (MACs) of chromatin arrangement in the nuclei of apparently normal cells adjacent to and distant from an invasive cancer area. MAC assessment is a hard task, since it requires a deep knowledge of morphologic features of chromatin arrangement. The aim of this work is to verify the reproducibility of the subjective evaluation of the expert on the basis of a decision support system (DSS) that automatically and objectively reproduces MAC diagnosis. A set of 61 patients with suspected clinical diagnosis for lung cancer has been taken into account. The scientist who first described MAC defined each patient as MAC positive or negative on the basis of the MAC diagnosis performed on all cells of the related cytologic sample. A DSS based on an artificial neural network has been set up to learn the relation between 14 morphometric and texture parameters, computed on each nucleus by image processing techniques, with the MAC diagnosis of the expert on each cell. The results show that an objective automatic assessment on MAC by the DSS can effectively support the MAC diagnosis. The method adopted in this approach may be also appropriate for other problems, where an automatic classification of visually inspected patterns of biological micro- and submicrostructure is needed.

Analysis of HLA-G expression in breast cancer tissues.

Among the different mechanisms by which cancer can elude the immune system, alterations in the expression of human leukocyte antigen (HLA) class I molecules on tumor cells may play a crucial role by impairing the HLA molecules interaction with T and natural killer (NK) cells specific receptors. More recently, aberrant expression of HLA-G has been described in different tumor tissues in addition to HLA class I downregulation. The HLA-G molecule is a nonclassical HLA class I antigen selectively expressed by trophoblast and thymic epithelial cells. Several studies reported that the HLA-G function might represent an additional mechanism of tumor immune escape, mainly inhibiting NK and cytotoxic T-cell activity. Here we report the analysis of HLA-G expression both at RNA level by reverse transcriptase-polymerase chain reaction and at protein level by Western blot and immunohistochemistry in 25 breast cancer patient tissues. The aim of this study was to elucidate the HLA-G gene expression pattern in breast tumor tissues and correlate it with HLA class I alterations. Our results demonstrated that HLA-G molecules expression was never found even in a group of patients revealing HLA class I total loss, and that HLA-G is not expressed in breast cancer tissue with a low-tumor grade (G1-G2) and minimal stromal contamination.

Endogenous reactivation of the RARbeta2 tumor suppressor gene epigenetically silenced in breast cancer.

Loss of expression of retinoic acid receptor beta2 (RARbeta2), a potent tumor suppressor gene, is commonly observed during breast carcinogenesis. RARbeta2 silencing can be traced to epigenetic chromatin changes affecting the RARbeta P2 promoter. Here we show that retinoic acid therapy fails to induce RARbeta2 in primary breast tumors, which carry a methylated RARbeta P2 promoter. DNA methylation leads to repressive chromatin deacetylation at RARbeta P2. By inducing an appropriate level of histone reacetylation at RARbeta P2 we could reactivate endogenous RARbeta2 transcription from unmethylated as well as methylated RARbeta P2 in breast cancer cell lines and xenograft tumors, and obtain significant growth inhibition both in vitro and in vivo. This study may have translational implications for breast cancer and other cancers carrying an epigenetically silenced RARbeta P2 promoter.