Factors Associated With Additional Axillary Disease in Patients With Positive Sentinel Lymph Nodes After Neoadjuvant Chemotherapy for Breast Cancer.

Background: In previous studies, breast cancer patients with positive sentinel lymph node(s) (SLN) after neoadjuvant chemotherapy (NAC) frequently had additional nonSLN involvement. Per guidelines, residual SLN disease warrants completion axillary lymph node dissection (cALND), which has increased morbidity. Given recent improvements in NAC, we hypothesized that nonSLN positivity may be lower than previously reported for certain subgroups.Methods: We retrospectively reviewed breast cancer patients who received NAC and had positive lymph nodes on SLN biopsy or targeted axillary dissection and underwent cALND at one institution in 1/2018-8/2023. Associations between nonSLN positivity and clinicopathologic factors were assessed with Fisher's exact test and multivariable logistic regression.Results: There were 122 female patients. Median age was 48 years. Initially, 15 patients (12.3%) were cN0 and 107 patients (87.7%) were cN1. Largest SLN deposit was macrometastasis in 96 patients (78.7%), micrometastasis in 23 patients (18.9%), and isolated tumor cells in 3 patients (2.5%). Overall, 53 patients (43.4%) had nonSLN involvement. NonSLN positivity was higher in patients with cN1, ER+ HER2-, ypT2-3, SLN macrometastasis, and multiple positive SLN. On multivariable analysis, cN1 and ER+ HER2- remained associated with nonSLN positivity.Discussion: Among patients with positive SLN after NAC, clinically node positive and ER+ HER2- patients were more likely to have nonSLN involvement. Our findings support guidelines to consider omitting cALND in clinically node negative patients. With improving NAC, optimal axillary sampling, and radiation, omitting cALND may be safe in some clinically node positive triple negative or HER2+ patients with low volume residual disease, but further research is needed.

Management of Infected Galactocele and Breast Implant with Uninterrupted Breastfeeding.

Infected breast implants during lactation present a rare but challenging clinical scenario that may result in early cessation of breastfeeding and unnecessary morbidity to mother and infant. We present the case of a 39-year-old African American primigravid woman with a history of bilateral retropectoral textured implants placed three years prior. Five days after delivering a healthy, full-term infant via cesarean section, she sought evaluation for nipple pain and trauma. She was instructed to use a nipple shield and pump every 2-3 hours in addition to breastfeeding, which resulted in iatrogenic hyperlactation. One week postpartum, the patient was started on antibiotics for presumed mastitis. Ultrasound demonstrated a complex fluid collection at the 12 o'clock periareolar position, as well as peri-implant fluid. She subsequently underwent aspirations of a periareolar complex galactocele and aspirations of peri-implant fluid. She continued on antibiotics without improvement. The patient proceeded to implant removal and definitive drainage of the galactocele at four months postpartum. Throughout her course, the patient provided her infant with exclusive breastmilk, including breastfeeding in the perioperative area of the operating room. This case demonstrates an example of safe surgical removal of infected breast implants and management of an infected galactocele without interruption of breastfeeding.

Management of idiopathic granulomatous mastitis in lactation: case report and review of the literature.

BACKGROUND: Idiopathic Granulomatous Mastitis (IGM) is a benign chronic inflammatory breast condition that mimics two common breast disorders: breast carcinoma and breast abscess. It can form breast masses, fistulae, and fluid collections, resulting in breast disfigurement with retraction and nipple areolar complex (NAC) inversion. IGM most often presents in women of childbearing age within a few years of pregnancy, and can significantly impact lactation. Despite the prevalence of this disease, no current literature describes an approach to managing IGM during breastfeeding. CASE PRESENTATION: A 28-year-old G3P2 patient of Native American origin presented to her obstetrician at 7 months pregnant with worsening left breast swelling and redness. She underwent a mammogram, ultrasound and core needle biopsy that confirmed the diagnosis of Idiopathic Granulomatous Mastitis. During the postpartum period, she underwent intralesional triamcinolone injections of her left breast. Due to the contraindication of breastfeeding after local steroid injection, the patient stopped breastfeeding from the affected breast and continued breastfeeding unilaterally. CONCLUSIONS: Idiopathic Granulomatous Mastitis is a challenging chronic inflammatory breast disease that affects women primarily in the reproductive years, with a higher incidence in patients of Hispanic, Native American, Middle Eastern, and African descent. Treatment of IGM during pregnancy and lactation has thus far not been addressed. We review the literature on the treatment of IGM in the non-lactating population, and propose considerations for treating breastfeeding women affected by this disease. Traditional treatment has included systemic immunosuppression and surgery, but newer literature demonstrates that intralesional injection of steroid can provide significant symptomatic relief to patients. A diagnosis of IGM does not preclude breastfeeding, though patients may experience challenges with milk production and latch on the affected breast. Individualized care should be provided, with considerations given to the following: side effects of systemic steroids, the need to wean a breast being treated with intralesional steroids, and augmentation of milk production on the unaffected breast to promote continued breastfeeding.

Heterochromatin position effects on circularized sex chromosomes cause filicidal embryonic lethality in Drosophila melanogaster.

Some circularized X-Y chromosomes in Drosophila melanogaster are mitotically unstable and induce early embryonic lethality, but the genetic basis is unknown. Our experiments suggest that a large region of X-linked satellite DNA causes anaphase bridges and lethality when placed into a new heterochromatic environment within certain circularized X-Y chromosomes. These results reveal that repetitive sequences can be incompatible with one another in cis. The lethal phenotype also bears a remarkable resemblance to a case of interspecific hybrid lethality.