Validation and update of a lymph node metastasis prediction model for breast cancer.

PURPOSE: This study aimed to validate and update a model for predicting the risk of axillary lymph node (ALN) metastasis for assisting clinical decision-making. METHODS: We included breast cancer patients diagnosed at six Dutch hospitals between 2011 and 2015 to validate the original model which includes six variables: clinical tumor size, tumor grade, estrogen receptor status, lymph node longest axis, cortical thickness and hilum status as detected by ultrasonography. Subsequently, we updated the original model using generalized linear model (GLM) tree analysis and by adjusting its intercept and slope. The area under the receiver operator characteristic curve (AUC) and calibration curve were used to assess the original and updated models. Clinical usefulness of the model was evaluated by false-negative rates (FNRs) at different cut-off points for the predictive probability. RESULTS: Data from 1416 patients were analyzed. The AUC for the original model was 0.774. Patients were classified into four risk groups by GLM analysis, for which four updated models were created. The AUC for the updated models was 0.812. The calibration curves showed that the updated model predictions were better in agreement with actual observations than the original model predictions. FNRs of the updated models were lower than the preset 10% at all cut-off points when the predictive probability was less than 12.0%. CONCLUSIONS: The original model showed good performance in the Dutch validation population. The updated models resulted in more accurate ALN metastasis prediction and could be useful preoperative tools in selecting low-risk patients for omission of axillary surgery.

Rare presentation of Brodie's abscess in the acromion process and the value of the penumbra sign.

A 17-year-old male patient presented with a swelling on his right shoulder 1 week after a fall. MRI revealed a superficial fluid collection of the acromion and trapezius muscle, with slight enhancement of the wall. The swelling burst open spontaneously after failed conservative therapy and was treated with surgical drainage and antibiotics. Tissue cultures showed a Staphylococcus aureus 1 year later, he presented with local red discolouration and a recurrent painful swelling that fluctuated at palpation. Radiographs showed a lytic lesion of the acromion process. MRI showed a sinus in the lytic cavity and a penumbra sign, which helped to identify this extremely rare occurrence of Brodie's abscess in the acromion process that was breaking through to the subcutaneous fat. The abscess was treated successfully with surgical drainage and intravenous antibiotics. In retrospect, the first MRI showed a small cortical indentation, with slight oedema of the acromion process.

[A patient with a painful swelling and a foot drop]. / Een man met een pijnlijke zwelling en een klapvoet.

A 72-year old patient presented himself at the outpatient clinic with a painful swelling on the dorsum of the left foot and a foot drop. The diagnosis was a complete rupture of the tibialis anterior tendon.

Minimal invasive fixation of proximal humeral fractures with an intramedullary nail: good results in elderly patients.

OBJECTIVE: To report on the results of a minimally invasive technique for the fixation of displaced proximal humeral fractures with a locked intramedullary nail. PATIENTS AND METHODS: All consecutive patients treated with a T2 intramedullary nail between 2004 and 2007 were evaluated. Thirty-three patients were included [mean age 78, m:f ratio (1:4)]. Fracture characteristics were classified according to AO and Neer (eighteen 2-part, eleven 3-part, five 4-part fractures). RESULTS: Functional outcome (Constant Score) was excellent in nine, satisfactory in eight and poor in three patients. Subjective outcome was satisfactory to good for patients with 2-part and 3-part fractures but poor for 4-part fractures. Major complications comprised four fixation failures, two cases of impingement and one deep infection. CONCLUSIONS: Minimally invasive fixation of displaced 2-part and 3-part humeral fractures in an elderly population shows satisfactory to excellent results in 80% of patients.