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PubMed1996

[Rhythmic lymph extravasation from a lymph fistula].

A 66-year-old woman with a chronic traumatic lymph fistula is described. Using the almost atraumatic fluorescence micro-lymphography the fistula could be precisely localized within the ulcer. Lymph flow from deep channels was rhythmic. This previously unknown phenomenon of rhythmic retrograde flow in a lymphatic fistula is probably due to the activity of contractile segments of lymph collectors and an important factor for the non-healing of ulcers.

Aged↗
PubMed2001

Sentinel lymph node biopsy as an alternative to routine axillary lymph node dissection in breast cancer patients.

Sentinel lymph node (SLN) biopsy is a useful way of assessing axillary nodal status and obviating axillary lymph node dissection (ALND) in patients with node-negative breast cancer. Because SLN technology is evolving rapidly, however, variation in technique is widespread, and no standardization has yet been accomplished. This review discusses the feasibility and accuracy of this procedure and suggests the optimal method for identifying the SLN and detecting micrometastases. Although the SLN can be successfully identified by either the dye-guided or gamma probe-guided method in experienced hands, identification is facilitated when the two techniques are used together. In the gamma probe-guided method, the use of a large-sized radiotracer (particle size, 200-1000 nm) may be preferred because only one or two SLNs are identified. To increase the chance of finding metastases in SLN, it is desirable to make step sections with hematoxylin and eosin staining on permanent and frozen sections. The addition of immunohistochemistry may improve the accuracy of SLN diagnosis. The intraoperative examination of imprint cytology may be useful in determining the status of the SLNs, but further studies are needed to establish whether it has additional value when combined with the frozen section. In practice, routine ALND can be avoided when there is documentation of extensive experience and a low false-negative rate with the technique in the hands of a particular surgeon and hospital team. Particularly, SLN biopsy is more successful and has a lower false-negative rate in patients with smaller tumors. However, investigation of long-term regional control and survival in a prospective randomized trial is necessary, before SLN biopsy can replace routine ALND as the preferred staging operation for women with breast cancer.

Breast↗
PubMed2003

Short-term morbidity of the upper limb after sentinel lymph node biopsy or axillary lymph node dissection for Stage I or II breast carcinoma.

BACKGROUND: The goals of sentinel lymph node biopsy (SLNB) are to improve axillary staging and reduce unnecessary axillary lymph node dissections (ALND), thereby reducing treatment-related upper-limb morbidity. In the current prospective study, short-term upper-limb morbidity was assessed after SLNB and/or ALND. METHODS: The study comprised 204 patients with Stage I/II breast carcinoma. Mean patient age was 55.6 years (standard deviation, 11.6). Sixty-six patients (32%) underwent SLNB only, and 138 (68%) underwent a Level I-II ALND. Assessment (preoperative [t0] and 6 weeks postoperative [t1]) included evaluation of shoulder range of motion, muscle strength, grip strength, pain, upper/forearm circumference, shoulder disability, and activities of daily life (ADL). RESULTS: Considerable treatment-related upper-limb morbidity was observed. Significant (P < 0.001) changes were found for pain, range of motion in forward flexion, abduction and abduction/external rotation, strength of shoulder abductors and elbow flexors, and in perceived disability in ADL. However, no significant difference in change of upper-limb function and ADL was found between the SLNB and ALND groups. CONCLUSIONS: Significant short-term treatment-related upper-limb morbidity exists after SLNB or ALND. There is no significant difference in short-term treatment-related morbidity between SLNB and ALND.

Activities of Daily Living↗
PubMed2005

Clinical outcome of patients with lymph node-negative breast carcinoma who have sentinel lymph node micrometastases detected by immunohistochemistry.

BACKGROUND: The ideal pathologic assessment of sentinel lymph nodes (SLNs) in patients with breast carcinoma remains controversial. The authors evaluated how detailed assessment of SLNs using immunohistochemistry (IHC) and serial sectioning would affect treatment decisions and outcomes in patients with breast carcinoma who had negative SLNs on standard hematoxylin and eosin staining. METHODS: The SLNs from patients who were treated between June 1998 and June, 1999 and who had negative lymph node status determined by hematoxylin and eosin staining (n = 84 patients) were evaluated further with serial sectioning and cytokeratin IHC. Patients were offered adjuvant therapy based on primary tumor factors. RESULTS: The median patient age was 57 years, and the median tumor size was 1.2 cm. At a median follow-up of 40.2 months, 81 patients (96%) were alive with no evidence of disease, 1 patient was alive with disease, 1 patient had died of disease, and 1 patient had died of other causes. Fifteen patients (18%) had micrometastases identified on IHC. Of the total 84 patients, information regarding adjuvant therapy was not available for 5 patients. Of the remaining 79 patients, 10 patients (13%) were not offered adjuvant chemotherapy but had positive SLN status determined by IHC. SLN status based on IHC evaluation did not correlate with age (P = 0.077), tumor size (P = 0.717), grade (P = 0.148), estrogen receptor status (P = 1.000), or lymphovascular invasion (P = 0.274). Furthermore, IHC-detected positive SLN status did not correlate with distant metastasis (P = 0.372) or overall or distant metastasis-free survival (P = 0.543 and P = 0.540, respectively). CONCLUSIONS: Although the finding of SLN micrometastases by IHC may change management in > 12% of patients, preliminary results suggested that such micrometastases do not affect outcomes significantly.

Adult↗
PubMed1986

Diffusion of a lymph-carried antigen in the fiber network of the lymph node of the rat.

A lymph-carried antigen is retained preferentially in those areas of the subcapsular sinus of a lymph node overlying the extrafollicular zone of the peripheral cortex. There, it becomes associated with the reticular fibers crossing these particular sinus areas. We wondered whether the antigen thereafter diffuses along the extensions of these fibers which form a peculiar network in the "cortical pathways of migration of circulating lymphocytes" (CPMCL), leading to the different cell populations effecting the immune responses. Fluorescein isothiocyanate (FITC)-conjugated antigens were injected locally into rats sacrificed 0.5-24 h later. The antigens diffused along the fibers of the CPMCL. It is proposed that this diffusion constitutes one mechanism of stimulation of recruited circulating lymphocytes and of orientation of their migration towards the proper effector-cell population.

Animals↗
PubMed2001

Intralaboratory validation of alternative endpoints in the murine local lymph node assay for the identification of contact allergic potential: primary ear skin irritation and ear-draining lymph node hyperplasia induced by topical chemicals.

We validated a two-tiered murine local lymph node assay (LLNA) with a panel of standard contact (photo)allergens and (photo)irritants with the aim of improving the discrimination between contact (photo) allergenic potential and true skin (photo)irritation potential. We determined ear weights to correlate chemical-induced skin irritation with the ear-draining lymph node (LN) activation potential. During tier I LLNAs, a wide range of concentrations were applied on three consecutive days to the dorsum of both ears. Mice were exposed to UVA light immediately after topical application to determine the photoreactive potential of some test chemicals. Mice were killed 24 h after the last application to determine ear and LN weights and LN cell counts. It was possible to classify the tested chemicals into three groups according to their threshold concentrations for LN activation and skin irritation: (1) chemicals with a low LN activation potential and no or very low skin irritation potential; (2) chemicals with a marked LN activation potential higher than a distinct skin irritation potential; and (3) chemicals with LN activation potential equal to or lower than their skin irritation potential. Group 1 consisted only of contact allergens, indicating that LN activation in the absence of skin irritation points to a contact allergenic activity. Since groups 2 and 3 comprised irritants and contact allergens, a tier II LLNA protocol was used to finally differentiate between true irritants and contact allergens. Briefly, mice were pretreated with mildly to moderately irritating concentrations of the chemical to the shaved back and after 12 days were challenged on the ears as described above in order to elicit a contact allergenic response in the ear skin and the ear-draining LN. With this approach, tier II LLNAs have to be conducted only in cases for which skin irritation potential is in the range of LN activation potential and no structure-activity relationship data indicating a contact allergenic hazard are available.

Administration, Topical↗
PubMed2005

Laparoscopic lymph node dissection around the inferior mesenteric artery for cancer in the lower sigmoid colon and rectum: is D3 lymph node dissection with preservation of the left colic artery feasible?

BACKGROUND: When we perform laparoscopic lymph node dissection around the inferior mesenteric artery (IMA), we preserve the left colic artery (LCA) to maintain the blood supply to the proximal sigmoid colon. In this study, we present our laparoscopic D2 and D3 lymph node (LN) dissection technique and evaluate its applicability and safety. METHODS: We performed LN dissection on 23 rectal and lower sigmoid colon cancer cases from April 2002 to December 2004. For D3 LN dissection, the incision to the mesosigmoid extends to just before the root of the IMA, which is exposed with an ultrasonic cutting and coagulating surgical device to avoid bleeding. Then, the arterial wall is exposed with a dissecting electrocautery spatula down to the LCA, at least 2 cm of which is exposed. Adipose tissue surrounding the IMA and inferior mesenteric vein is dissected. For D2 LN dissection, we partially expose the IMA to confirm the location of the LCA. RESULTS: The mean times taken for D2 and D3 LN dissections were 36.2 and 68.2 min, respectively. Both procedures took longer in male patients. There was a trend for the procedure overall to take less time in female patients. However, D2 dissection took significantly longer in male than female patients (p < 0.05). In women, D3 dissection took significantly longer than D2 (p < 0.05), but this trend was not seen in men. Increased experience among surgeons with this procedure was associated with significantly faster LN dissections in men (p < 0.05), but not in women (p = 0.493). Pearson product moment analysis identified a relationship between body mass index (BMI) and the time taken for D2 LN dissection (r = 0.765), but not D3 LN dissection (r = 0.158). There was no treatment-related morbidity with this technique. CONCLUSIONS: This method was safe and feasible for all patients in this series, but takes longer to perform in male patients.

Aged↗
PubMed2001

Intraoperative pathologic evaluation of a breast cancer sentinel lymph node biopsy as a determinant for synchronous axillary lymph node dissection.

BACKGROUND: Intraoperative pathologic evaluation of a breast cancer sentinel lymph node (SLN) biopsy permits synchronous axillary lymph node dissection (ALND), but frozen section is time consuming and potentially inaccurate. This study evaluated intraoperative gross examination and touch prep analysis (TPA) of a breast cancer SLN biopsy as determinants for synchronous ALND. METHODS: Intraoperative gross examination/TPA were performed on the SLN of consecutive breast cancer patients from 1997 to 2000. Patients with an intraoperative "positive" SLN underwent synchronous ALND. Intraoperative results were compared with the final pathology. RESULTS: Thirty-seven of 150 patients had a positive SLN on final pathology. Intraoperative gross examination/TPA identified 54% (20 of 37) of these patients. All intraoperative "positive" patients underwent synchronous ALND. Of 17 "false-negative" findings, 53% (9 of 17) had micrometastatic disease. There were no "false-positive" results. Overall sensitivity and specificity were 54% and 100%, respectively. CONCLUSIONS: Gross examination/TPA are simple, rapid techniques for the intraoperative evaluation of a breast cancer SLN. As there were no false-positive results, the rationale behind SLN biopsy was preserved. These techniques permitted synchronous ALND in over half of all patients with a positive SLN. This represents a potential benefit to the patient by eliminating a second hospitalization for delayed ALND.

Adult↗
PubMed2005

An axilla scoring system to predict non-sentinel lymph node status in breast cancer patients with sentinel lymph node involvement.

BACKGROUND: Axillary lymph node dissection (ALND) is the current standard of care for breast cancer patients with sentinel lymph node (SN) involvement. However, the SN is the only involved axillary node in a significant proportion of these patients. Here we examined factors predictive of non-SN involvement in patients with a metastatic SN, in order to develop a scoring system for predicting non-SN involvement. MATERIALS AND METHODS: This study was based on a prospective database of 337 patients who underwent SN biopsy for breast cancer, of whom 81 (24%) were SN-positive; we examined factors predictive of non SN involvement in the 71 of these 81 women who underwent complementary ALND. All clinical and histological criteria were recorded and analysed according to non-SN status, by using Chi-2 analysis, Student's t-test, and multivariate logistic regression. RESULTS: Univariate analysis showed a significant association between non-SN involvement and histological primary tumor size (p=0.0001), SN macrometastasis (p=0.01), the method used to detect SN metastasis (H&E versus immunohistochemistry) (p=0.03), the number of positive SNs (p=0.049), the proportion of involved SNs among all identified SNs (p=0.0001) and lymphovascular invasion (p=0.006). Histological primary tumor size (p=0.006), SN macrometastasis (p=0.02) and the proportion of involved SNs among all identified SNs (p=0.03) remained significantly associated with non-SN status in multivariate analysis. Based on the multivariate analysis, we developed an axilla scoring system (range 0-7) to predict the likelihood of non-SN metastasis in breast cancer patients with SN involvement. CONCLUSION: In patients with invasive breast cancer and a positive SN, histological primary tumor size, the size of SN metastases, and the proportion of involved SNs among all identified SNs were independently predictive of non-SN involvement.

Adult↗
PubMed2006

Re-fixation in a lymph node revealing solution is a powerful method for identifying lymph nodes in colorectal resection specimens.

AIM: To verify an impact of a lymph node revealing solution (LRS) on the number of lymph nodes (LN) revealed in colorectal resection specimens. MATERIAL AND METHOD: Fifty-nine cases of rectosigmoid carcinomas divided into two subgroups-stage pT2&3 (20 cases) and ypT2&3 (with pre-operative radiotherapy-39 cases)-were formalin fixed for 42-72 h, serially sectioned and re-fixed in LRS containing ethanol, diethyl ether, glacial acetic acid, and formalin for 24 h. The number of LNs was matched to a control group consisting of 34 cases of colorectal carcinoma, 14 pT2&3 and 20 ypT2&3 rectosigmoid carcinomas examined routinely. Results were statistically tested by Student's t-test. RESULTS: In the study group the total number of revealed LNs was 869, range 1-48, average 14.7 per specimen, median 15. In the control group the number of LNs was 200, range 0-13, average 5.9 per specimen, median 6. The difference between the study and the control group was statistically significant (P = 0.05). CONCLUSION: Using LRS leads to a significant increase in the number of revealed LNs in colorectal resection specimens and makes it possible to find more than 12 LNs in a majority of stage pT2 and pT3 adenocarcinomas.

Acetic Acid↗
PubMed2006

Negative sentinel lymph node accurately predicts negative status of pelvic lymph nodes in uterine cervix carcinoma.

OBJECTIVE: The significance of negative sentinel lymph nodes (SLN) is important in the staging and treatment of melanoma and a few other cancers, but is controversial in uterine cervix carcinoma. Our study was aimed at correlating the SLN status in cervical carcinoma with non-sentinel lymph nodes (non-SLN), in a uniform and well controlled population. METHODS: This study includes 36 patients with stage I and IIA cervical carcinoma and bilaterally negative SLN on final pathology. SLN were identified using blue dye and radioisotopic techniques. Frozen section examination was performed for all SLN; the rest of the tissue was formalin fixed and paraffin embedded. The protocol used for SLN was also applied for non-SLN. For each block, six 4-micro m thick sections were cut at 40 micro m intervals and stained with H and E; an additional section taken between the 3rd and 4th levels was imunostained using AE1/AE3 cytokeratin. RESULTS: The mean age for the study population was 39 years (range 25-76); the number of SLN ranged from 2 to 6 (mean 2.7) and the non-SLN from 8 to 49 (mean 23) per case. No metastasis was found in any SLN and non-SLN by step sections and IHC. CONCLUSION: Our study demonstrates that bilaterally negative SLN on final pathology accurately predict the absence of metastases in non-SLN in cervical carcinoma. If confirmed by larger trials, these results may influence the clinical management of early cervical cancer.

Adult↗
PubMed2001

Predictors of positive axillary lymph nodes after sentinel lymph node biopsy in breast cancer.

OBJECTIVE: The purpose of this study was to determine the factors that predict the presence of metastasis in nonsentinel lymph nodes (SLN) when the SLN is positive. METHODS: A prospective database was analyzed and included patients who underwent SLN biopsy for invasive breast cancer from July 1997 to August 2000 (n = 442). One hundred (22.6%) patients had one or more positive SLNs, and were analyzed to determine factors that predicted additional positive axillary nodes. RESULTS: Of the 100 patients with a positive SLN, 40 patients (40%) had additional metastasis in non-SLNs. The only significant variables that predicted non-SLN metastasis were tumor lymphovascular invasion (P = 0.004), extranodal extension (P < 0.001), and increasing size of the metastasis within the SLN (P = 0.011). In analyzing just those patients who had lymphovascular invasion, extranodal extension, and a SLN metastasis > 2mm, 92% were found to have additional positive nodes. CONCLUSIONS: In patients with invasive breast cancer and a positive sentinel lymph node, lymphovascular invasion, extranodal extension, and increasing size of the metastasis all significantly increase the frequency of additional positive nodes.

Adult↗
PubMed1991

Immune responses of the ovine lymph node to Chlamydia psittaci. A cellular study of popliteal efferent lymph.

The popliteal efferent lymphatics were cannulated in sheep of two categories, seronegative or immune to Chlamydia psittaci. Following subcutaneous injection of live C. psittaci or control material into the draining area of the popliteal node, sequential samples of efferent lymph were collected and analysed. Both categories of sheep responded to C. psittaci with increased outputs of lymphocytes and blast cells. Numbers of blast cells rose both absolutely and as a proportion of the total. Plasmablasts increased in number only in seronegative sheep. Outputs of total T cells (CD5+), helper T cells (CD4+), cytotoxic/suppressor T cells (CD8+) and non-helper, non-suppressor T cells (T19) were maximal 4 and 7 days after challenge in immune and seronegative sheep, respectively. Proportionally, CD4+ T cells declined, CD8+ T cells increased and T19 cells were unaltered with time after infection. Chlamydial antigens could not be demonstrated in the cells of efferent lymph by an immunoperoxidase method. The results of this preliminary study show that both T and B cell responses are involved in immunity to C. psittaci.

Abortion, Veterinary↗
PubMed2002

Determination of the sensitising activity of the rubber contact sensitisers TMTD, ZDMC, MBT and DEA in a modified local lymph node assay and the effect of sodium dodecyl sulfate pretreatment on local lymph node responses.

A modified local lymph node assay (LLNA) was used to determine the sensitising activity of four chemicals used for the production of natural rubber latex products. Tetramethylthiuramdisulfide (TMTD), 2-mercaptobenzothiazole (MBT) and zincdimethyldithiocarbamate (ZDMC), three moderate human sensitisers, and diethylamine (DEA) a known human sensitiser, were epicutaneously administered on the ear and the proliferating activity in the draining (auricular) lymph node (LN) was determined by ex vivo (3)H-thymidine incorporation. Consistent results were obtained for TMTD and ZDMC with stimulation indices (SI) above 3, identifying these compounds as sensitiser, while for DEA and MBT inconsistent results were obtained. For all parameters determined such as LN weight, LN cell number, cell proliferation per 2 x 10(6) cells, and cell proliferation per LN statistical significant increases were observed. The SI, expressed as cellular proliferation per LN or per animal (left and right LN combined), was the most sensitive parameter with an optimum at day 5 after start of treatment.Furthermore, we investigated whether the use of sodium dodecyl sulfate (SDS) was able to enhance weak responses in the LLNA. SDS treatment with dosages of 10% and higher resulted in a SI above 3, while a dosage of 1% SDS showed no activity. Pretreatment with 1% SDS 1 h before application of the rubber chemicals enhanced the responses to these chemicals consistently, identifying also DEA and MBT as sensitisers. Our results indicate that SDS had synergistic activity on the LN responses of the administered rubber chemicals in the LLNA. For the moderately responding sensitisers TMTD and ZDMC both IFN-gamma and IL-4 production was observed. For the weakly responding sensitisers DEA and MBT both IFN-gamma and IL-4 cytokine production was only observed after pretreatment of the animals with 10% SDS. For 10% and 20% SDS, inducing approximately a SI of 20 in the LLNA, no induction of cytokines was observed.

Allergens↗
PubMed2003

A model for teaching sentinel lymph node mapping and excision and axillary lymph node dissection.

BACKGROUND: The surgical skills laboratory increasingly provides opportunities for training and practice in basic surgical procedures. STUDY DESIGN: This article describes a new method for teaching trainees sentinel lymph node mapping and excision and level I/level II axillary dissection. The training session uses cadaver head and torso segments through T6 implanted with radioactive discs to simulate the sentinel node. This model is the first described to provide trainees the opportunity to practice mapping of the sentinel node and excision of the node once identified. RESULTS: A group of PGY2 and PGY3 residents participated in this laboratory experience with defined objectives, syllabus material, and training session. All participants successfully harvested the sentinel node and completed a level I/level II axillary dissection with faculty supervision and feedback. The residents rated the experience as outstanding and felt that it increased their confidence in their ability to perform the procedure in the operating room. CONCLUSIONS: Use of cadavers for surgical skills training is only one of a variety of options currently available to provide practice for surgical housestaff in the surgical skills laboratory. Such a model might well have application in training courses for surgeons in practice and courses accompanying clinical trials for sentinel lymph node mapping and excision.

Axilla↗
PubMed2004

Cost comparison of two surgical strategies in the treatment of breast cancer: sentinel lymph node biopsy versus axillary lymph node dissection.

OBJECTIVES: The feasibility and accuracy of sentinel lymph node biopsy (SLNB) in the treatment of breast cancer is widely acknowledged today. The aim of our study was to compare the hospital-related costs of this strategy with those of conventional axillary lymph node dissection (ALND). METHODS: A retrospective study was carried out to determine the total direct medical costs for each of the two medical strategies. Two patient samples (n = 43 for ALND; n = 48 for SLNB) were selected at random among breast cancer patients at the Centre Leon Bérard, a comprehensive cancer treatment center in Lyon, France. Costs related to ALND carried out after SLNB (either immediately or at a later date) were included in SLNB costs (n = 18 of 48 patients). RESULTS: Total direct medical costs were significantly different in the two groups (median 1965.86 Euro versus 1429.93 Euro, p = 0.0076, Mann-Whitney U-test). The total cost for SLNB decreased even further for patients who underwent SLNB alone (median, 1,301Euro). Despite the high cost of anatomic pathology examinations and nuclear medicine (both favorable to ALND), the difference in direct medical costs for the two strategies was primarily due to the length of hospitalization, which differs significantly depending on the technique used (9-day median for ALND versus 3 days for SLNB, p < 0.0001). CONCLUSIONS: A lower morbidity rate is favorable to the generalization of SLNB, when the patient's clinical state allows for it. From an economic point of view, SLNB also seems to be preferred, particularly because our results confirm those found in two published studies concerning the cost of SLNB.

Axilla↗
PubMed2001

Micro-metastases in axillary lymph nodes: an increasing classification and treatment dilemma in breast cancer due to the introduction of the sentinel lymph node procedure.

BACKGROUND: Sentinel lymph node (SN) biopsy will increasingly replace axillary lymph node dissection (ALND) for staging in breast cancer. For daily practice, examination of the SN by serial sectioning (SS) and/or immunohistochemistry (IHC) is being promoted. Use of these techniques may result into stage migration due to the increased detection of micro-metastases. The consequence may be overshooting of patients with adjuvant therapy, as the prognostic relevance of (small) micro-metastases and isolated tumor cells is unclear. METHODS: The prognostic impact of micro-metastases is determined by reviewing ALND studies with a follow up of at least 5 years, including more than 100 patients, before the SN era. Furthermore, studies in which conventionally haematoxylin-eosin (H&E) negative SNs are investigated for occult metastases by SS and/or IHC are reviewed. RESULTS: In only one of eight studies, occult metastases were an independent risk factor for reduced survival. The outcome is dependent on the size of the nodal metastasis. IHC and SS as used in the SN procedure indeed induce a shift from pNO to pN1a (according to TNM). CONCLUSION: By the thorough pathologic examination of the SN, isolated tumor cells and micro-metastases are more frequently detected. We propose to classify small micro-metastases (<0.5 mm) in a separate pN1a(min) category (min for minimal) to prevent stage migration. As the prognostic relevance of isolated tumor cells and (small) micrometastases has not been proven, the value of adjuvant therapy can be questioned for patients with otherwise good prognostic factors.

Axilla↗
PubMed2003

Survival of lymph node-negative breast cancer patients in relation to number of lymph nodes examined.

OBJECTIVE: To assess the relationship between number of lymph nodes examined and survival of patients diagnosed with node-negative localized breast cancer using a large sample of patients from population-based cancer registries in the United States. SUMMARY BACKGROUND DATA: Conflicting results have been reported from studies on the relationship between number of lymph nodes examined and survival of patients diagnosed with node-negative localized breast cancer. METHODS: The study included 69,543 patients diagnosed in 1988-97 with localized invasive node-negative breast cancer reported to nine population-based registries in the U.S. National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) Program of population-based cancer registries. Hazard ratios for groups defined by number of nodes examined were analyzed in Cox proportional hazards regression models that included age, tumor size and grade, race/ethnicity, and other variables. RESULTS: A significantly higher risk of death from breast cancer was found among patients with 0, 1 to 3, or 4 to 10 nodes examined than with 20-plus nodes examined, even among patients with tumors 2 cm or smaller. CONCLUSIONS: Future studies of survival of node-negative patients, by number of nodes examined, should include information on comorbidity and treatment.

Adult↗