Do changes in lymph node status distribution explain trends in survival of breast cancer patients in Denmark?

IGHV mutational status and outcome for patients with chronic lymphocytic leukemia upon treatment: a Danish nationwide population-based study

Patients with chronic lymphocytic leukemia and unmutated immunoglobulin heavy-chain variable region gene (IGHV) have inferior survival from time of treatment in clinical studies. We assessed real-world outcomes based on mutational status and treatment regimen in a nationwide population-based cohort, comprising all 4,135 patients from the Danish chronic lymphocytic leukemia registry diagnosed between 2008 and 2017. In total, 850 patients with known mutational status received treatment: 42% of patients received intensive chemoimmunotherapy consisting of fludarabine, cyclophosphamide plus rituximab, or bendamustine plus rituximab; 27% received chlorambucil in combination with anti-CD20 antibodies or as monotherapy, and 31% received other, less common treatments. No difference in overall survival from time of first treatment according to mutational status was observed, while treatment-free survival from start of first treatment was inferior for patients with unmutated IGHV. The median treatment-free survival was 2.5 years for patients treated with chlorambucil plus anti-CD20, and 1 year for those who received chlorambucil monotherapy. The 3-year treatment-free survival rates for patients treated with fludarabine, cyclophosphamide plus rituximab, and bendamustine plus rituximab were 90% and 91% for those with mutated IGHV, and 76% and 53% for those with unmutated IGHV, respectively, and the 3-year overall survival rates were similar for the two regimens (86-88%). Thus, it appears that, in the real-world setting, patients progressing after intensive chemoimmunotherapy as first-line therapy can be rescued by subsequent treatment, without jeopardizing their long overall survival. Intensive chemoimmunotherapy remains a legitimate option alongside targeted agents, and part of a personalized treatment landscape in chronic lymphocytic leukemia, while improved supportive care and treatment options are warranted for unfit patients.

Impact of the sentinel node frozen section result on the probability of additional nodal metastases as predicted by the MSKCC nomogram in breast cancer

OBJECTIVE

Sentinel lymph node frozen section is used to obviate the need for a second operation in breast cancer patients with involved nodes. However, the overall sensitivity, specificity and accuracy of sentinel lymph node frozen section are debated, and the impact of sentinel lymph node frozen section positivity on the risk of additional nodal metastases is not known and was the focus of this investigation.

METHODS

We used our hospital record system to identify 176 sentinel lymph node biopsies done out of 354 cases of Stage T1-3N0 breast cancers managed from 2005 to 2007 and evaluated the sentinel lymph node frozen section results against the predictions of additional nodal metastases based on the Memorial Sloan-Kettering Breast Cancer Nomogram which is a validated tool for this purpose.

RESULTS

Sentinel lymph node metastases size was an independent predictor of sentinel lymph node frozen section sensitivity and those with macrometastases had 15 times the odds (odds ratio, 15.4; 95% confidence interval, 3.4-69.1) of having a true-positive frozen section when compared with those with micrometastases. The breast cancer nomogram predicted that the latter patients have a very low probability of additional nodal metastases with a median probability at 10% (inter-quartile range, 7-14%).

CONCLUSIONS

A negative sentinel lymph node frozen section is also associated with a low probability of additional nodal metastases. Additional prognostic factors in the breast cancer nomogram are of little clinical impact because the most predictive factor in the nomogram is the method of detection.

Why did the breast cancer lymph node status distribution improve in Denmark in the pre-mammography screening period of 1978-1994?

BACKGROUND

Danish breast cancer patients diagnosed in 1978-1994 experienced a trend over time towards a more favourable distribution of lymph node status at time of diagnosis, which was not due to mammography screening. We investigated how this trend could be explained by patient characteristics at diagnosis: age (biological processes), calendar period (e.g. environmental changes), birth cohort (living conditions over a life time), post-menopausal status (a predictor of less favourable nodal status), and tumour diameter (a marker of detection time).

MATERIAL AND METHODS

The data set consisted of 22 955 patients aged 30-69 years at time of diagnosis with known lymph node status, known tumour diameter, known menopausal status, and clinically detected tumours, available from the Danish Breast Cancer Cooperative Group (DBCG). Age, period, cohort, menopausal status, and tumour diameter were used as predictors in generalised linear models with either node-positive status (at least one of the excised lymph nodes being tumour-positive) or severely node-positive status (at least half of the excised lymph nodes being tumour-positive) as outcomes. Lymph node status was assessed both empirically and estimated using an EM algorithm in order to reduce misclassification.

RESULTS AND DISCUSSION

We found that the improved lymph node status distribution was most likely a period effect due to a combination of earlier detection of clinical tumours, explaining most of the trend in node-positive breast cancer and half of the trend in severely node-positive breast cancer, and some unknown factor affecting lymph node status but not necessarily other tumour characteristics.