Prélèvement de ganglions sentinelles dans les carcinomes intracanalaires du sein (± micro-invasion)

Role of axillary staging in women diagnosed with ductal carcinoma in situ with microinvasion

BACKGROUND

Axillary staging via sentinel node biopsy (SLNB) in patients with ductal carcinoma in situ with microinvasion (DCISM) is routinely performed but remains controversial with regard to the risk-benefit ratio.

METHODS

Retrospective single-institution review of patients with diagnosis of DCISM (invasive tumor ≤ 0.1 cm). Age, clinicopathologic data, and follow-up were recorded.

RESULTS

Of 90 patients, 33% were diagnosed by core needle biopsy (CNB), 37% by excisional biopsy, and 29% were upstaged from DCIS on CNB to DCISM at final operation. Three (10%) of 30 patients with DCISM on CNB were upstaged to invasive cancer on final pathology. Median age at diagnosis was 58.9 years (range: 30-89). Lumpectomy was performed in 45% of patients and mastectomy in 55%. Mean number of sentinel nodes was 2.59 (SE 0.17). Six (6.9%) of 87 patients with DCISM as final diagnosis had a positive SLNB (four lumpectomies, two mastectomies). There was no correlation with any clinicopathologic features, including palpable DCIS, DCIS grade/necrosis, or age at diagnosis. All six SLNB-positive patients had a complete axillary dissection; two had additional disease. Median follow-up time was 74.2 months (range: 2-169). In-breast recurrence was seen in three patients (5%), regardless of SLN status, DCIS grade, or necrosis. Two patients developed distant metastasis. Overall survival was 94.19% at 5 years for DCISM and 100% for DCISM with nodal disease.

CONCLUSION

DCISM comprises 0.6% of breast cancer diagnoses at our institution. There is a low likelihood of nodal spread; however, a lack of identifiable clinicopathologic features associated with a positive SLNB limits selective SLNB use.

The sentinel lymph node procedure for patients with preoperative diagnosis of ductal carcinoma in situ: risk factors for unsuspected invasive disease and for metastatic sentinel lymph nodes

BACKGROUND

Occult invasive disease could be found at definitive histology in patients initially diagnosed with large ductal carcinoma in situ (DCIS). Sentinel lymph node (SLN) biopsy is a reliable and minimally invasive procedure providing axillary information and avoiding a second operation in this particular group of patients. The aim of our study was to assess the value of SLN biopsy in patients with large DCIS who are at highest risk for being upstaged to invasive carcinoma.

PATIENTS AND METHODS

The study included 195 patients diagnosed with DCIS upon initial core biopsy and undergoing SLN biopsy. Many features were correlated with the presence of unsuspected invasive disease and positive SLN biopsy using univariate and multivariate analyses.

RESULTS

Of the 110 patients with pure DCIS, seven patients (6%) had a metastatic lymph node; 31 patients (16%) were found to have invasive disease upon final histology. Univariate analysis of predictors of unsuspected invasive carcinoma showed that patients having a preoperative biopsy that indicated DCIS with microinvasion (DCISM) or large DCIS were at a higher risk of invasive carcinoma after histological examination of the operative specimen. Of the 31 patients who were upstaged to invasive carcinoma at final histology, seven patients (22%) had a positive SLN biopsy. The analysis of predictors of positive SLN in our study shows that diffuse DCIS requiring mastectomy is the main risk factor for SLN metastasis.

CONCLUSION

There are no real predictive factors for invasive disease in patients with an initial diagnosis of DCIS or DCISM. Our study supports the value of SLN biopsy in patients with a preoperative DCISM biopsy or patients with a large pure DCIS biopsy requiring mastectomy.

Cancer canalaire in situ du sein avec micro-invasion. Place du ganglion sentinelle

OBJECTIVES

To investigate the role of sentinel lymph node biopsy for microinvasive ductal carcinoma in situ of the breast.

PATIENTS AND METHODS

From January 2001 to January 2006, lymphatic mapping was performed using radiocolloid and/or blue dye technique. Full axillary lymph node dissection was accomplished systematically in 10 instances at the beginning of the study, and furthermore when the sentinel node was involved (macrometastatic or micrometastatic disease).

RESULTS

Identification rate was 98% (40/41), the unsuccessful procedure occurred after incisional biopsy for diagnosis. The number of sentinel nodes removed was 2 in average (1-5). Sentinel node involvement was found in 10% of cases (4/40): 1 sentinel node macrometastasis pN1, 2 sentinel node micrometastases determined by hematoxylin and eosin staining pN1 (mi), 1 sentinel node micrometastasis detected only by immunohistochemical staining pN0 (mi).

DISCUSSION AND CONCLUSION

Sentinel lymph node sampling should not be currently applied for management of every ductal carcinoma in situ of the breast but a selective utilization is proposed in documented high risk subset of patients according to clinical, mammographic, and histologic features obtained by percutaneous biopsies. Ductal carcinoma in situ (DCIS) with proved or suspected microinvasion could be scheduled for sentinel node procedure a fortiori in cases undergoing mastectomy because of extensive DCIS before the occurrence of disturbances of lymphatic drainage induced by surgical breast dissection.

Is there an indication for sentinel node biopsy in patients with ductal carcinoma in situ of the breast? A review

Ductal carcinoma in situ (DCIS) of the breast is defined as a proliferation of malignant epithelial cells within breast ducts without evidence of invasion through the basement membrane. The detection rate of DCIS of the breast has dramatically increased since the mid-1980s as the result of the widespread use of screening mammography. DCIS currently represents about 15-25% of all breast cancers detected in population screening programmes. Although inherently a non-invasive disease, occult invasion with the potential of lymph node metastases may occur. Where performing an axillary lymph node dissection-or-not for DCIS used to be an important dilemma, the same now holds for the sentinel node biopsy. This article reviews the potential role of the sentinel node biopsy (SNB) in patients with DCIS. We conclude that based on the current literature, there is in general no role for a SNB in DCIS. A SNB should only be considered in patients with an excisional biopsy diagnosis of high risk DCIS (grade III with palpable mass or large tumour area by imaging) as well as in patients undergoing mastectomy after a core or excisional biopsy diagnosis of DCIS, although SNB may be contraindicated in many of the latter patients because of lesion size and/or multifocality. Even in these patients the value of a positive SN, containing mostly isolated tumour cells, is questionable.

Cancers canalaires in situ du sein avec micro-invasion

OBJECTIVE

Specify the role of axillary lymph node removal in micro-invasive in situ duct carcinomas (DCIS-MI) of the breast with a series of 107 consecutive cases.

METHODS

Single-centre, retrospective, anatomoclinical study with application of the European guidelines adopting as pathological definition the presence of areas of micro-invasion not exceeding 1mm. Axillary lymph node dissection was systematically complete and was preceded by the search for the sentinel node in 10 patients using the isotope method.

RESULTS

Lymph node invasion was revealed in 8 cases in the global population (7.5%). All the cases except one exhibited typical deleterious histological features: comedo architectural sub-type, high nuclear grade, and size of the lesion>3 cm. The lymph node invasion was of 18.5% in the sub-group of high-grade micro-invasive comedo-carcinomas measuring more than 3 cm.

CONCLUSION

Contrary to those exhibiting pure DCIS, DCIS-MI patients require surgical exploration of the armpit, the most appropriate modalities of which are currently debated: classical axillary lymph node dissection or search for the sentinel lymph node; the selective lymphadenectomy procedure is not yet a consensually validated technique.

The relevance of occult axillary micrometastasis in ductal carcinoma in situ: a clinicopathologic study with long-term follow-up

BACKGROUND

Ductal carcinoma in situ (DCIS) represents 20% of newly diagnosed breast carcinoma cases. Historically, the incidence of axillary metastasis in DCIS has been small (1-2%) and its significance has been debated. It is widely known that serial sections of lymph nodes coupled with keratin immunohistochemistry (IHC) increases identification of micrometastasis. The advent of sentinel lymph node evaluation underscores the need to reevaluate the significance of occult micrometastases in DCIS.

METHODS

Patients with DCIS and negative axillary lymph nodes from 1974 to 1992 were selected from the Saint Barnabas Medical Center Tumor Registry. All diagnoses were confirmed, and paraffin blocks were retrieved after acceptance into the study. Seven serial sections were obtained from each block and evaluated with two cytokeratin IHC stains. Clinical follow-up ranged from 10 to 28 years.

RESULTS

One hundred two patients were included in the study. Micrometastases were identified in 13 patients (13%), mostly on 1 level and composed of microscopic clusters in the subcapsular sinus. Seven of these lymph node-positive patients (58%) had high-grade comedo DCIS, 4 (33%) had intermediate grades of various types of DCIS, and one had a low-grade micropapillary DCIS. The overall disease recurrence rate was 12%, but micrometasis was not detected in any of the patients who developed disease recurrence.

CONCLUSIONS

Serial IHC evaluation of lymph nodes dramatically increased the identification of occult micrometastasis. However, IHC detected micrometastasis has no apparent clinical significance in DCIS, based on the current long-term clinicopathologic study. Therefore, the authors questioned the significance of occult micrometastasis, identified by IHC, in DCIS of any type and extent. Further evaluation and follow-up of lymph node micrometastases in patients with invasive tumors of various sizes are needed. The current findings would not support altering the stage of patients with DCIS and micrometastasis detected by IHC only.