Ductal Carcinoma In Situ with Microinvasion on Core Biopsy: Evaluating Tumor Upstaging Rate, Lymph Node Metastasis Rate, and Associated Predictive Variables.

INTRODUCTION: The role of sentinel lymph node biopsy (SLNB) when ductal carcinoma in situ with microinvasion (DCISM) is identified on core biopsy is unclear. OBJECTIVE: Our aim was to assess the upstage rate to invasive cancer and axillary lymph node metastasis in patients diagnosed with DCISM, and whether predictive variables could be identified that may help inform who would most likely benefit from a surgical axillary evaluation. METHODS: We performed a retrospective review of 70 patients diagnosed with DCISM on core biopsy. Patients with concomitant or prior invasive cancer were excluded. Demographic, clinical, radiographic, histologic, and treatment data were collected. Fisher's exact test and univariable and multivariable logistic regression were performed to identify variables that may be associated with tumor upstaging and nodal metastasis. Time-to-event distributions were summarized using the Kaplan-Meier method. RESULTS: On final surgical pathology, 49 patients (70%) had a final diagnosis of DCISM or T1mi cancer, whereas 21 patients (30%) were upstaged to measurable invasive cancer (> 1 mm). One of 49 patients (2%) with DCISM on final pathology and 4 of 21 patients (19%) with measurable invasive cancer showed sentinel lymph node metastases. CONCLUSION: Although the upstage rate to measurable invasive cancer in our cohort of patients with DCISM on core biopsy was 30%, findings of a positive SLNB remain low at 7%. No predictive variables were identified to inform whether the routine practice of SLNB may be omitted in some patients with DCISM.

Rate of radial scars by core biopsy and upgrading to malignancy or high-risk lesions before and after introduction of digital breast tomosynthesis.

PURPOSE: Radial scars (RS) commonly present mammographically as architectural distortions, but these lesions may be associated with non-invasive and invasive breast cancer. Digital breast tomosynthesis (DBT) has resulted in higher detection rates of architectural distortion particularly in patients with dense breast tissue. We hypothesized that rates of clinically relevant lesions confirmed surgically would be lower in patients who received DBT imaging compared with those who received standard digital breast imaging. METHODS: We performed a retrospective review of 223 patients diagnosed with pure RS by core biopsy and surgical excision before and after DBT was introduced. The rate of upgrading to malignancy or high-risk lesion was evaluated. Demographics, biopsy type, and histologic data were analyzed. Univariable logistic regression analysis was used to identify variables that may be associated with upgrading. RESULTS: The rate of identifying RS increased from 0.04-.13% (P < 0.0001) with DBT imaging. The upgrade rate on surgical specimen to invasive or non-invasive cancer was similar before and after DBT; 6% versus 3%, as were findings of a high-risk lesion; 12% versus 22%. No predictive factors were identified for patients upgraded to malignant neoplasms or high-risk lesions. CONCLUSIONS: The likelihood of identifying RS has increased with DBT imaging, but rates of upgrading to a malignant neoplasm or high-risk lesion were similar to those before DBT. Although the rate of upgrading to malignancy after DBT was low, an excisional biopsy should be considered as 22% of patients were upgraded to high-risk lesions. These patients are candidates for chemoprevention and/or high-risk surveillance.

Posterior distraction forces of the posterior longitudinal ligament stratified according to vertebral level.

INTRODUCTION: Although considered significant in resisting midline intervertebral disc herniation, the posterior longitudinal ligament (PLL) has had relatively few studies performed regarding its morphology and function. We performed the present experiment to discern the amount of posterior tensile force necessary to disrupt the PLL at each vertebral level. MATERIALS AND METHODS: Twenty-five adult cadavers underwent laminectomies of vertebrae C1 to S1. After removal of the spinal cord, nerve roots, and dura mater, the PLL was identified for each vertebral level and a steel wire placed around its waist in the midline and a tensile gauge attached and posterior tension applied perpendicular to the spine. Forces necessary to failure of the PLL were noted for each vertebral level. RESULTS: The PLL was found to be stronger in the thoracic spine compared to the cervical and lumbar vertebrae (P < 0.05). Dividing the vertebral levels in this manner, we found an average posterior distraction force to failure of 48.3 N in the cervical region, 61.3 N in the thoracic region, and 48.8 N in the lumbar region. CONCLUSIONS: These findings support clinical observations that thoracic disc herniation is rare. We hypothesize that this clinical observation is partially due to a stronger PLL in the thoracic spine.

Surgical anatomy and landmarks for the basal vein of rosenthal.

OBJECT: The basal vein of Rosenthal (BV) courses from the premesencephalic cistern, through the ambient cistern, and terminates in the quadrigeminal cistern. The aim of this study was to describe and quantitate the surgical anatomy of this structure and specifically to provide landmarks for identifying this vessel along its course. These data may be of use, for example, to surgeons using subtemporal operative approaches through regions where this vessel is concealed. METHODS: The authors examined 15 latex-injected adult cadaveric brains (30 sides) to delineate the morphological characteristics of the BV. Dissections of the BV were then performed and measurements were made between this structure and the tentorial incisura at the anterior, middle, and posterior borders of the lateral midbrain. All specimens were found to have a left and right BV with varying morphological characteristics. The mean distance between the BV and posterior cerebral artery at the midpoint of the lateral midbrain was 16 mm. The BV was always found superomedial to the posterior cerebral artery along the lateral aspect of the midbrain, and the BV ranged in diameter from 1 to 5 mm. The BV drained into the vein of Galen in all but two specimens. The mean distances from the tentorial edge to the BV at the anterior, middle, and posterior borders of the lateral midbrain were 11, 1 3, and 4 mm, respectively. No statistically significant differences were found when comparing left and right sides or male and female specimens. CONCLUSIONS: The authors hope that these data will help the neurosurgeon operating near the BV to avoid injury to this important structure.