Contemporary management of breast cancer

Role of sentinel lymph node biopsy in high-risk ductal carcinoma in situ patients

BACKGROUND

The role of sentinel lymph node biopsy (SLNB) for ductal carcinoma in situ (DCIS) is poorly defined. However, up to 20% of patients with DCIS will have invasive carcinoma; these patients require staging for axillary metastasis. The aim of this study was to identify patients with a core biopsy diagnosis of DCIS who may benefit from SLNB.

METHODS

In a prospective study, we performed SLNB on patients with a preoperative diagnosis of >2.5 cm of high-grade DCIS or DCIS when mastectomy was indicated.

RESULTS

Sixty-two patients underwent surgery for high-grade DCIS, and 35 of these patients underwent SLNB. Postsurgical excision histology revealed invasive disease in 20 patients, 19 of whom had undergone SLNB. Before the adoption of SLNB in selected DCIS patients, all 20 with occult invasive disease would have required second surgery axillary staging (P < .01, chi-square test).

CONCLUSIONS

SLNB should not be performed routinely for all patients with an initial diagnosis of DCIS. However, selective lymphadenectomy may be a useful clinical adjuvant in selected high-risk DCIS patients.

Emerging approaches for prophylaxis and management of oropharyngeal mucositis in cancer therapy

Oral mucositis is a common treatment-limiting side effect of cancer therapy that may have a significant impact on quality of life and on the cost of care. Oral mucositis is the most distressing complication of cancer therapy as reported by head and neck cancer patients, in patients receiving dose-dense myelosuppressive chemotherapy and in patients receiving haematopoietic stem cell transplant. Mucositis may increase the risk of local and systemic infection, particularly in myelosuppressed patients. Severe oral mucositis can lead to the need to interrupt or discontinue cancer therapy, and thus may impact cure of the primary disease. Current care of patients with mucositis is essentially palliative, and includes appropriate oral hygiene, nonirritating diet and oral care products, topical palliative mouth rinses, topical anaesthetics and use of systemic opioid analgesics. Emerging approaches for prevention and treatment of oral mucositis are developing based on an increasing understanding of the pathobiology of mucosal damage and repair. New interventions are expected to be administered based on the mechanisms of initiation, progression and resolution of the condition. The approval by the FDA of keratinocyte growth factor (palifermin; Amgen) in 2004 represents a new step in prevention of oral mucositis in stem cell transplant patients based on the increasing understanding of the pathogenesis of mucositis. Progress in the prevention and management of mucositis will improve quality of life, reduce cost of care and facilitate completion of more intensive cancer chemotherapy and radiotherapy protocols. Improved management of mucositis may allow implementation of cancer treatment protocols that are currently excessively mucotoxic, but have potentially higher cure rates of the malignant disease.

The role of sentinel lymph node biopsy in ductal carcinoma in situ

AIM

To review the role of sentinel lymph node (SLN) biopsy in the surgical management of patients with ductal carcinoma in situ (DCIS).

METHODS

A search was conducted of Medline and the National Library of Medicine to identify key articles concerning DCIS, SLN biopsy (SLNB) and axillary dissection. Further relevant articles were obtained from the references cited in the literature.

RESULTS

Up to 20% of patients with a core biopsy diagnosis of DCIS will be later up-staged based on an invasive component identified on the excision specimen. Quality assurance in breast screening programmes requires minimally invasive pre-operative diagnosis and also axillary sampling in the case of documented invasive disease. As an effective and validated procedure, SLNB represents a paradigm shift in the surgical management of the axilla for patients with invasive breast cancer. It remains undefined which, if any, subgroups of patients with DCIS should undergo SLNB.

CONCLUSION

Axillary lymphadenectomy is an overtreatment for patients with DCIS. Performing a SLNB during the initial procedure may avoid a second operation in some DCIS patients who are diagnosed with occult invasive disease at their definitive operation. When predictors of hidden invasive disease are clarified by further study, SLNB may be used in the management of selected high-risk DCIS patients.

Perinucleolar Compartment Prevalence Has an Independent Prognostic Value for Breast Cancer

The perinucleolar compartment (PNC) is a multicomponent nuclear structure enriched with RNAs transcribed by RNA pol III and RNA binding proteins. Studies in cultured cells showed an association between PNC and transformed phenotype. To evaluate the relationship between structure and malignancy in vivo, we examined PNC prevalence (the percentage of cells containing at least one PNC) in normal and cancerous paraffin-embedded breast tissues using immunohistochemistry against a PNC-associated protein. Five hundred nuclei in the most active area of each sample were scored for PNC prevalence. The results show that PNC prevalence significantly correlates with the progression of breast cancer (by the criteria of staging). PNC prevalence in primary tumors, lymph nodes, and distant metastases shows a stepwise increase from a median of 23% in primary tumors to ∼100% in distant metastases. In addition, univariate and multivariate (controlling for tumor size and grade) analyses show that early-stage patients with invasive ductal carcinomas containing a higher PNC prevalence have a significantly poorer prognosis. These findings link PNC prevalence with the progression of breast cancer in vivo and suggest that PNC-containing cells have metastatic advantages. These findings also show the potential of PNC prevalence as a prognostic marker for breast cancer.

Lymphatic mapping and sentinel lymphadenectomy for breast cancer

Lymphatic mapping and sentinel lymphadenectomy has become an important tool for axillary lymph node staging in women with early-stage breast cancer. This review examines data regarding the staging accuracy, indications and technical aspects of the procedure, and clinical trials investigating the technique. Multiple studies now confirm that sentinel lymphadenectomy accurately stages the axilla and is associated with less morbidity than axillary dissection. Blue dye, radiocolloid, or both can be used to identify the sentinel node, and several injection techniques may be used successfully. Many patient factors previously thought to affect accuracy of the procedure have now been shown to be of limited significance. The indications for the procedure are expanding, and the histopathologic evaluation of the sentinel node and the role of lymphoscintigraphy have been clarified. Clinical trials are now underway that will determine the prognostic significance of micrometastases and the therapeutic benefit of axillary dissection in women with and without sentinel node metastases. Incorporation of sentinel lymphadenectomy into routine clinical practice will maintain accurate axillary staging with lower morbidity and improved quality of life for women with early-stage breast cancer.

Development of malignant breast microcalcifications after neoadjuvant chemotherapy in advanced breast cancer

The increased interest in the use of neoadjuvant chemotherapy for patients with locally advanced or large tumors at initial presentation necessitates the recognition of sequelae of this therapy. This article describes the interval appearance of malignant, linear-branching, microcalcifications during neoadjuvant chemotherapy for locally advanced breast cancer. Mammographically the malignant microcalcifications appeared only in the region of the breast where the primary tumor was found. Pathologically only a subpopulation of malignant cells responded to the chemotherapy, demonstrating viability of the majority of the tumor, with cell death only in the subpopulation. With the increased use of neoadjuvant chemotherapy, it is important to recognize previously undescribed mammographic findings secondary to this therapeutic approach.

Treatment of the axilla by tangential breast radiotherapy in women with invasive breast cancer

BACKGROUND

The objective of this study was to determine if standard tangential breast radiation covered the sentinel lymph node in women with invasive breast cancer.

METHODS

Women with invasive breast cancer treated by lumpectomy, radiotherapy and sentinel node biopsy at our institution were included in this study if the sentinel lymph node site had been marked with a clip. Plain films were used to determine if the clip fell within the tangential fields.

RESULTS

Between April 1999 and May 2001, 36 women with invasive breast cancer treated by lumpectomy, sentinel lymph node biopsy and breast radiation were identified. Median age was 56 years (range 34 to 80) with a median tumor size of 1.1 cm (range 0.3 to 2.9 cm). The clip marking the sentinel lymph node fell within the tangential fields in 34 of 36 (94%) of the patients. The radiation dose to the clip area was greater than 4,400 cGy in 50% of those calculated by three-dimensional techniques.

CONCLUSIONS

The sentinel lymph node is located within classic tangential fields in the overwhelming majority of women with invasive breast cancer. The extent of the radiation fields, and ultimately the final dose, may need to be modified if the intent is for prophylactic treatment.

Clinical axillary recurrence in breast cancer patients after a negative sentinel node biopsy

BACKGROUND

The purpose of this study was to determine the axillary recurrence rate in breast cancer patients with a negative sentinel lymph node who did not have an axillary node dissection.

METHODS

Sentinel lymphadenectomy for breast cancer patients, without axillary node dissection if the node was negative, was introduced in 1998 at our institution. This study includes those women with a negative sentinel lymph node. Adjuvant chemotherapy was administered based on primary tumor characteristics. If breast radiotherapy was used, no attempt was made to include the axilla.

RESULTS

From January 1998 to December 2001, 206 patients (208 breast cancers) had a negative sentinel lymph node. The median age at diagnosis was 56 years and median tumor size was 1.2 cm. With a median follow-up of 26 months, there have been 3 axillary recurrences with a clinical sentinel lymph node false negative rate of 1.4%.

CONCLUSIONS

In this study, the clinical false negative rate of a sentinel lymph node biopsy is 1.4%. Our study provides further evidence supporting the use of sentinel lymphadenectomy in women with breast cancer.