Addressing the Gray Zone in Affirmative Mastectomy: An Analysis of Fischer 2 Patients.

BACKGROUND: Surgical decision making in gender-affirming mastectomy (GAM) is based on a patient's classification using the Fischer scale. Fischer 1 patients are excellent candidates for periareolar (PA) approach and Fischer 3 patients almost exclusively undergo double incision with free nipple grafting (DIFNG). Fischer 2 patients are in a gray zone in which decision making is more challenging. In this patient population, periareolar approaches can lead to increased complication and revision rates but free grafting procedures seem excessive. We have created a treatment algorithm to address Fischer 2 patients and additionally developed a novel technique, the batwing, to provide patients with more options. METHODS: A retrospective chart review was undertaken to analyze the Fischer classification of all patients undergoing top surgery by a single surgeon at an academic institution from 2014 to 2021. The choice of surgical technique used as well as the outcomes of GAM among Fischer 2 patients was analyzed. RESULTS: Four hundred four patients underwent GAM, and 51 (11%) had Fischer 2 classification. The surgical techniques used were PA (27%), batwing (39%), nipple-sparing double incision (NSDI, 24%), and DIFNG (10%). Of those, 10% had major complications and 20% requested revision for contour irregularities. Major complication rates for PA, batwing, NSDI, and DIFNG were as follows: 2 of 14 patients (14%), 1 of 20 patients (5%), 1 of 12 patients (8%), and 1 of 5 patients (20%), respectively. The revision rate by technique was PA (36%), batwing (15%), NSDI (17%), and DIFNG (0%). CONCLUSIONS: For Fischer 2 patients, batwing and NSDI techniques avoid the need for free nipple graft while providing better exposure, improved control of nipple-areolar complex position, and decreased rate of revision as compared with the PA technique. The complication rate was not significantly different. We present an algorithm accounting for Fischer grade, unique patient characteristics, and patient desires.

[Hyperpigmentation reveals Addison's disease in a pregnant woman].

A 31-year-old woman was admitted to the local department of endocrinology for control of known anti-TPO positive hypothyroidism during pregnancy. The clinician noticed a remarkable hyperpigmentation. Primary adrenal insufficiency was diagnosed and treatment with cortico- and mineralosteroids commenced. Diagnosis of primary adrenal insufficiency during pregnancy is challenging as many symptoms overlap with normal symptoms of pregnancy. The usual diagnostic criteria cannot be used due to the altered hormone concentrations during pregnancy.

Surgeon Gender-Related Differences in Operative Coding in Plastic Surgery.

BACKGROUND: Numerous studies in the medical and surgical literature have discussed the income gap between male and female physicians, but none has adequately accounted for the disparity. METHODS: This study was performed to determine whether gender-related billing and coding differences may be related to the income gap. A 10 percent minimum difference was set a priori as statistically significant. A cohort of 1036 candidates' 9-month case lists for the American Board of Plastic Surgery over a 5-year span (2014 to 2018) was evaluated for relationships between surgeon gender and work relative value units, coding information, major and minor cases performed, and work setting. Data were deidentified by the American Board of Plastic Surgery before evaluation. The authors hypothesized that work relative value units, average codes per case, major cases, and minor cases would be at least 10 percent higher for male than for female physicians. RESULTS: Significant differences were found between male and female surgeons in work relative value units billed, work relative value units billed per case, and the numbers of major cases performed. The average total work relative value units for male surgeons was 19.34 percent higher than for female surgeons [3253.2 (95 percent CI, 3090.5 to 3425.8) versus 2624.1 (95 percent CI, 2435.2 to 2829.6)]. Male surgeons performed 14.28 percent more major cases than female surgeons [77.6 percent (95 percent CI, 72.7 to 82.7 percent) versus 90.5 percent (95 percent CI, 86.3 to 94.9 percent); p = 0.0002]. CONCLUSIONS: The authors' findings support the hypothesis that billing and coding practices can, in part, account for income differences between male and female plastic surgeons. Potential explanations include practices focusing on larger and more complex operative cases and differences in coding practices.

ACR Appropriateness Criteria® Transgender Breast Cancer Screening.

Breast cancer screening recommendations for transgender and gender nonconforming individuals are based on the sex assigned at birth, risk factors, and use of exogenous hormones. Insufficient evidence exists to determine whether transgender people undergoing hormone therapy have an overall lower, average, or higher risk of developing breast cancer compared to birth-sex controls. Furthermore, there are no longitudinal studies evaluating the efficacy of breast cancer screening in the transgender population. In the absence of definitive data, current evidence is based on data extrapolated from cisgender studies and a limited number of cohort studies and case reports published on the transgender community. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Aesthetic Surgery in Plastic Surgery Academia.

BACKGROUND: Aesthetic surgery is a critical component of academic plastic surgery. As institutions are placing increased focus on aesthetic surgery, there is an opportunity to identify factors that facilitate the creation and maintenance of successful aesthetic plastic surgery programs. OBJECTIVES: The aim of this study was to conduct a national survey to evaluate the current state of academic aesthetic surgery and to identify factors that contribute to success. METHODS: A REDCap 122-question survey was developed and validated by members of the Academic Aesthetic Surgery Roundtable (AASR). The national survey was distributed to department chairs and division chiefs with active ACGME-approved plastic surgery programs (n = 92). Responses underwent Pearson's chi-squared, Wilcoxon rank-sum, and postselection inference analyses. AASR members convened to interpret data and identify best practices. RESULTS: Responses were received from 64 of 92 queries (69.6%). The multivariate analysis concluded traits associated with successful academic aesthetic surgery practices included the presence of aesthetic surgery-focused, full-time faculty whose overall practice includes >50% aesthetic surgery (P = 0.040) and nonphysician aesthetic practitioners who provide injection services (P = 0.025). In the univariate analysis, factors associated with strong aesthetic surgery training programs included resident participation in faculty aesthetic clinics (P = 0.034), aesthetic research (P = 0.006), and discounted resident aesthetic clinics (P < 0.001). CONCLUSIONS: The growth of academic aesthetic surgery practices represents a significant opportunity for advancement of resident training, departmental financial success, and diversification of faculty practices. By identifying and sharing best practices and strategies, academic aesthetic surgery practices can be further enhanced.

Academics in the Pandemic: Early Impact of COVID-19 on Plastic Surgery Training Programs.

The COVID-19 global pandemic has impacted plastic surgery training in the United States, requiring unprecedented measures to prepare for potential surges in critically ill patients. This study investigates how plastic surgery programs responded to this crisis, as well as how successful these changes were, through a survey of program directors and of residents at academic training programs in the United States. METHODS: Two separate anonymous online surveys were conducted via REDCap between April 16 and June 4, 2020. The first survey was distributed to program directors, and the second was distributed to plastic surgery residents. Resident responses were then subdivided for an analysis between geographic regions. RESULTS: Of the 59 program director responses (43.7%), the majority of programs implemented a platoon approach for resident coverage. A minority did the same for attending coverage. In total, 92% transitioned to virtual didactics only. Plastic surgery residents covered alternative services at 25% of responding institutions, and an additional 68% had a plan in place for responding to personnel shortages. Overall, residents were satisfied with their program's response in a variety of categories. When subdivided based on geographic region, respondents in the Northeast and Northwest were less satisfied with resident wellness, personal and loved ones' safety, and program communication. CONCLUSIONS: With the possibility of a "second wave," successful methods of academic programs adapting to the pandemic should be communicated to reduce the future impact. Increased frequency of communications between program directors and residents can improve mental health and wellness of the resident population.

Silicone granuloma mimicking Breast Implant Associated Large Cell Lymphoma (BIA-ALCL): a case report.

We describe the case of a 75-year-old woman with textured silicone implants who was referred to our institution with concern for implant rupture and Breast Implant Associated Anaplastic Large Cell Lymphoma (BIA-ALCL). After explantation and pathologic evaluation, she was diagnosed with silicone granuloma and adenitis, though her presentation mimicked BIA-ALCL.

Providing Gender Confirmation Surgery at an Academic Medical Center: Analysis of Use, Insurance Payer, and Fiscal Impact.

BACKGROUND: Expansion of insurance coverage for gender confirmation surgery (GCS) has led to a large demand for GCS in the US. We sought to determine the financial impact of providing comprehensive GCS services at an academic medical center. METHODS: This was a cross-sectional study of patients older than 18 years who presented for GCS between January 1, 2015 and July 31, 2018 at a single academic medical center. The use of GCS services and associated work relative value units is reported. Departmental and hospital-level operating (profit) margins are reported relative to other hospital services, as well as the payer mix. RESULTS: A total of 818 patients underwent 970 GCS procedures between January 2015 and July 2018. Mean (SD) age was 35.32 (12.84) years. Four hundred and ninety-three (60.3%) patients underwent a masculinizing procedure, and 325 (39.7%) had a feminizing procedure. The most commonly performed procedure was chest masculinization (n = 403). The GCS case volume grew to generate 23.8% (plastic surgery) and 17.8% (urology) of total annual departmental work relative value units, and was associated with positive operating margins after recouping new faculty hiring costs. There were positive operating margins for GCS procedures for the hospital system that compare favorably with other common procedures and admissions. Medicare and Medicaid remained the most common payer throughout the study period, but dropped from 70% in 2015 to 48% in 2018. CONCLUSIONS: We found that providing GCS at our academic medical center is profitable for both the surgical department and the hospital system. This suggests such a program can be a favorable addition to academic medical centers in the US.

Differences in Chest Measurements between the Cis-female and Trans-female Chest Exposed to Estrogen and Its Implications for Breast Augmentation.

BACKGROUND: Gender confirming primary breast augmentation is becoming more common. The purpose of this study was to compare the demographic and anatomical differences in cis-female and trans-female populations. METHODS: This was a retrospective analysis of trans-female patients and cis-female patients undergoing primary breast augmentation at a single institution. Analysis included patient demographics and preoperative chest measurements including sternal notch to nipple distance (SSN), breast width (BW), nipple to inframammary fold distance (N-IMF), and nipple to midline distance (N-M). Continuous variables were compared using independent t tests, and discrete variables were compared using Pearson's χ2 tests. RESULTS: Eighty-two trans-female and 188 cis-female patients undergoing primary breast augmentation were included. Trans-female patients were older (40.37 versus 34.07), more likely to have psychological comorbidities (50% versus 12.23%), and had a higher body mass index, 27.46 kg/m2 versus 22.88 kg/m2 (P = 1.91E-07), than cis-female patients. Cis-female patients most commonly had an ectomorph body habitus (52% versus 26%), whereas trans-female patients most commonly had an endomorph body habitus (40% versus 7%). Pseudoptosis or ptosis was more commonly seen in cis-female patients (P = 0.0056). There were significant differences in preoperative breast measurements including sternal notch to nipple distance, BW, and N-M between groups, but not in N-IMF. The ratio of BW/N-IMF was statistically significant (P = 2.65E-07 on right), indicating that the similarity in N-IMF distance did not adjust for the difference in BW. CONCLUSIONS: The trans-female and cis-female populations seeking primary breast augmentation have significant demographic and anatomical differences. This has implications for surgical decision-making and planning to optimize outcomes for trans-female patients.

What is "Nonbinary" and What Do I Need to Know? A Primer for Surgeons Providing Chest Surgery for Transgender Patients.

BACKGROUND: Most transgender research focuses on patients who identify within the gender binary of either trans-male or trans-female. This largely omits understanding of the "nonbinary" gender identity as it pertains to surgical care. OBJECTIVES: We sought to describe a single-institution experience of chest-affirming procedures performed in nonbinary patients, including patient characteristics, surgical techniques, practice pearls, and outcomes. METHODS: This was an observational study of nonbinary patients who underwent "chest-affirming surgery" from 2012 to 2017. Demographic and surgical data were collected. A postoperative questionnaire assessing quality of life and body image outcomes was administered. RESULTS: A total of 458 patients with gender dysphoria underwent chest surgery; 58 (13%) patients were nonbinary. All nonbinary patients indicated female sex was assigned at their birth (100%). The most commonly performed procedure was the double incision technique with nipple grafts (72%), followed by the double incision technique without nipple grafts (19%). On a Likert scale, patients reported improved quality of life (4.88, SD ± 0.34), comfort with exercise (4.07, SD ± 0.98), sex life (4.02, SD ± 0.92), and comfort with physical appearance with (4.97, SD ± 0.18) and without clothes (4.69, SD ± 0.47). CONCLUSIONS: Chest surgery for nonbinary patients comprises a considerable proportion of transgender surgery practice, and surgeons who provide affirming care should be familiar with the unique characteristics and treatment options for this population.

Data on European seafood biomass production by country, sectors, and species in 2004-2014 and on ecological characteristics of the main species produced.

In this data article, we present the 2004-2014 average European seafood production volume by production sector, country, and species. The production data originates from the Food and Agriculture Organisation of the United Nations (FAO) and covers three production sectors: Marine fisheries, marine aquaculture, and freshwater production. We present the main ecological characteristics of each species produced or harvested. These species characteristics were retrieved from various published sources and include biological sensitivity to harvesting and temperature ranges for the most important species. These indices were weighted by each species production volume in order to produce maps of European country's color-coded by their overall temperature range, maximum temperature, and biological sensitivity within each production sector.

Evidence-Based Strategies for the Prehabilitation of the Abdominal Wall Reconstruction Patient.

It is inherently challenging to achieve successful surgical outcomes for ventral hernia repairs. For complex ventral hernias, attempts to reconstruct the abdomen in patients who are overweight, deconditioned, malnourished, chronically infected or inflamed, have previous hernia recurrence, or otherwise carry a number of serious comorbidities affecting their surgical fitness are a major undertaking requiring careful preparation and planning. As the rate of abdominal wall reconstructions rises, so does the complexity of these procedures. One could argue that the prehabilitation of these patients is equally, if not more, important than the surgical technique itself. To achieve desirable outcomes and avoid surgical-site occurrences (SSOs), the surgeon must familiarize him/herself with ways to optimize a patient preoperatively. Understanding and identifying the aforementioned modifiable risk factors for SSOs is crucial. It is also important to recognize the impact that acute changes in the microbiome perioperatively can have on the postoperative success. Familiarizing oneself with the available literature for these patients is imperative. This review presents discussion and guidance for understanding the challenges and best practices for providing hernia surgery and abdominal wall reconstruction and achieving durable outcomes, with minimal SSOs.

The flame retardant DE-71 (a mixture of polybrominated diphenyl ethers) inhibits human differentiated thyroid cell function in vitro.

BACKGROUND: Normal thyroid function is essential for general growth and metabolism, but can be affected by endocrine disrupting chemicals (EDCs). Polybrominated diphenyl ethers (PBDEs) have been used worldwide to reduce flammability in different materials and are suspected to be EDCs. The production of the commercial Penta- and OctaBDE mixtures is banned, but DecaBDEs and existing products may leak PBDEs into the environment. Our aim was to investigate the effect of the PentaBDE mixture DE-71 on human thyroid cells in vitro. MATERIALS AND METHODS: Primary human thyroid cells were obtained as paraadenomatous tissue and cultured in monolayers. The influence of DE-71 on cyclic adenosine monophosphate (cAMP) and thyroglobulin (Tg) production was examined in the culture medium by competitive radioimmunoassay and enzyme-linked immunosorbent assay, respectively. Real-time quantitative PCR analysis of thyroid-specific genes was performed on the exposed cell cultures. PBDE concentrations were determined in cellular and supernatant fractions of the cultures. RESULTS: DE-71 inhibited Tg-release from TSH-stimulated thyrocytes. At 50 mg/L DE-71, mean Tg production was reduced by 71.9% (range: 8.5-98.7%), and cAMP by 95.1% (range: 91.5-98.8%) compared to controls). Expression of mRNA encoding Tg, TPO and TSHr were significantly inhibited (p<0.0001, p = 0.0079, and p = 0.0002, respectively). The majority of DE-71 added was found in the cell fraction. No cytotoxicity was found. CONCLUSIONS: DE-71 inhibited differentiated thyroid cell functions in a two phase response manner and a concentration-dependent inhibition of Tg and cAMP production, respectively, as well as expression of mRNA encoding Tg, TPO and TSHr. Our findings suggest an inhibiting effect of PBDEs on thyroid cells.

Effects of the Commercial Flame Retardant Mixture DE-71 on Cytokine Production by Human Immune Cells.

INTRODUCTION: Although production of polybrominated diphenyl ethers (PBDEs) is now banned, release from existing products will continue for many years. The PBDEs are assumed to be neurotoxic and toxic to endocrine organs at low concentrations. Their effect on the immune system has not been investigated thoroughly. We aimed to investigate the influence of DE-71 on cytokine production by peripheral blood mononuclear cells (PBMCs) stimulated with Escherichia Coli lipopolysaccharide (LPS) or phytohaemagglutinin-L (PHA-L). MATERIAL AND METHODS: PBMCs isolated from healthy donors were pre-incubated with DE-71 at various concentrations and subsequently incubated with the monocyte stimulator LPS, or the T-cell activator PHA-L. Interferon (IFN)-γ, interleukin (IL)-1ß, IL-2, IL-4, IL-6, IL-8, IL-10, tumor necrosis factor (TNF)-α, IL-17A, and IL-17F were quantified in the supernatants by Luminex kits. RESULTS: At non-cytotoxic concentrations (0.01-10 µg/mL), DE-71 significantly enhanced secretion of IL-1ß, IL-6, CXCL8, IL-10, and TNF-α (p<0.001-0.019; n = 6) from LPS-stimulated PBMCs. IFN-γ, TNF-α, IL-17A, and IL-17F (p = <0.001-0.043; n = 6) secretion were enhanced from PHA-L-stimulated PBMCs as well. Secretion of IL-1ß, IL-2, IL-10, IL-8 and IL-6 was not significantly affected by DE-71. CONCLUSIONS: We demonstrate an enhancing effect of DE-71 on cytokine production by normal human PBMCs stimulated with LPS or PHA-L ex vivo.

Phthalates Are Metabolised by Primary Thyroid Cell Cultures but Have Limited Influence on Selected Thyroid Cell Functions In Vitro.

Phthalates are plasticisers added to a wide variety of products, resulting in measurable exposure of humans. They are suspected to disrupt the thyroid axis as epidemiological studies suggest an influence on the peripheral thyroid hormone concentration. The mechanism is still unknown as only few in vitro studies within this area exist. The aim of the present study was to investigate the influence of three phthalate diesters (di-ethyl phthalate, di-n-butyl phthalate (DnBP), di-(2-ethylhexyl) phthalate (DEHP)) and two monoesters (mono-n-butyl phthalate and mono-(2-ethylhexyl) phthalate (MEHP)) on the differentiated function of primary human thyroid cell cultures. Also, the kinetics of phthalate metabolism were investigated. DEHP and its monoester, MEHP, both had an inhibitory influence on 3'-5'-cyclic adenosine monophosphate secretion from the cells, and MEHP also on thyroglobulin (Tg) secretion from the cells. Results of the lactate dehydrogenase-measurements indicated that the MEHP-mediated influence was caused by cell death. No influence on gene expression of thyroid specific genes (Tg, thyroid peroxidase, sodium iodine symporter and thyroid stimulating hormone receptor) by any of the investigated diesters could be demonstrated. All phthalate diesters were metabolised to the respective monoester, however with a fall in efficiency for high concentrations of the larger diesters DnBP and DEHP. In conclusion, human thyroid cells were able to metabolise phthalates but this phthalate-exposure did not appear to substantially influence selected functions of these cells.

Avoiding the Unfavorable Outcome with Wise Pattern Breast Reduction.

Wise pattern breast reduction remains the most popular method of performing moderate- to large-sized breast reductions in the United States. Shape distortion after breast reduction can be a result of design flaw, execution of technique, or the result of postoperative complications. This article focuses primarily on optimal design and intraoperative techniques for prevention of shape distortion. By carefully considering the design of the skin resection pattern, choosing and designing an appropriate pedicle, preventing skin necrosis, and managing scars, shape distortion after Wise pattern breast reduction can be minimized.

Migration of phthalates on culture plates - an important challenge to consider for in vitro studies.

Phthalates are endocrine disruptors of the reproductive system and suspected to influence many other organ and hormone systems. They are also semi-volatile organic compounds present in the gas phase in the environment. Their mode of action has been investigated in numerous in vitro studies. Multi-well culture plates are typically used to study phthalates in cell cultures. In a pilot study, we observed evidence of phthalate migration in 24-well culture plates. As this has not previously been described, we investigated the phenomenon in more detail. Primary human thyroid epithelial cell cultures (n = 8 cultures) were exposed to either di-ethyl phthalate (DEP), di-n-butyl phthalate (DnBP), mono-n-butyl phthalate (MnBP) or di-(2-ethylhexyl) phthalate (DEHP). Measurement of phthalate metabolites by mass spectrometry demonstrated that the short-branched DEP was able to migrate to adjacent wells when added to cell culture plates. DnBP also seemed to be able to migrate, unlike the long-branched DEHP or the monoester MnBP which did not seem to have this ability. High background levels of phthalate metabolites were also observed, which might compromise results from low dose phthalate studies. In conclusion, the migration of phthalates which is probably caused by their volatile properties might lead to false interpretation of study results.

Axillary Lymph Node Dissection Is a Risk Factor for Major Complications After Immediate Breast Reconstruction.

BACKGROUND: Complications after immediate breast reconstruction pose a significant challenge to the reconstructive surgeon. Known risk factors include smoking, obesity, age, and adjuvant oncologic therapies. Less is known about the association between axillary lymph node dissection (ALND) and the development of postoperative complications. METHODS: We conducted a retrospective study of all patients who underwent immediate breast reconstruction after mastectomy at our institution over a 10-year period. Our outcome was an occurrence of a major complication within 90 days postoperatively. For each patient, we recorded data on demographics, smoking status, pertinent medical history, reconstruction type, adjuvant chemotherapy and radiation, tumor pathology, and whether an ALND was performed. Odds ratios (OR) were calculated to estimate the risk of a complication if an ALND was performed. RESULTS: One hundred eighty-four women, with 270 surgically treated breasts, were identified as having mastectomy with immediate reconstruction between 2002 and 2012. Mean age was 49.4 years (range, 25-84 years). There were 71 mastectomies with ALND performed, with 22 complications, and 199 mastectomies without ALND, with 20 complications (31% complication rate vs 10%, respectively; OR, 3.84; P < 0.001). When adjusted for reconstruction type, smoking history, obesity, age, presence of invasive disease, chemotherapy, and radiation therapy, the OR for complications was 3.49 (P < 0.01). The most common complication was infection in both groups. CONCLUSIONS: Mastectomy with ALND is associated with a 3-fold increase in risk of major complications in women undergoing immediate breast reconstruction, even after adjustment for known risk factors and confounders. Further studies are warranted to elucidate how ALND leads to these complications and what measures can reduce their occurrence.

Gene expression signatures of breast cancer stem and progenitor cells do not exhibit features of Warburg metabolism.

INTRODUCTION: Cancers are believed to adapt to continual changes in glucose and oxygen availability by relying almost exclusively on glycolytic metabolism for energy (i.e. the Warburg effect). The process by which breast cancers sustain growth in avascular tissue is thought to be mediated via aberrant hypoxia response with ensuing shifts in glycolytic metabolism. Given their role in initiating and perpetuating tumors, we sought to determine whether breast cancer stem and progenitor cells play an instrumental role in this adaptive metabolic response. METHODS: Breast cancer stem/progenitor cells were isolated from invasive ductal carcinomas, and benign stem cells (SC) were isolated from reduction mammoplasty tissues. Relative expression of 33 genes involved in hypoxia and glucose metabolism was evaluated in flow cytometrically isolated stem and progenitor cell populations. Significance between cohorts and cell populations was determined using Student's 2-tailed t test. RESULTS: While benign stem/progenitor cells exhibited few significant inter-group differences in expression of genes involved in hypoxia regulation or glucose metabolism, breast cancer stem/progenitor cells demonstrated significant inter-group variability. Breast cancer stem/progenitor cells adapted to microenvironments through changes in stem cell numbers and transcription of glycolytic genes. One of four breast cancer stem/progenitor cells subpopulations exhibited an aerobic glycolysis gene expression signature. This subpopulation comprises the majority of the tumor and therefore best reflects invasive ductal carcinoma tumor biology. Although PI3K/AKT mutations are associated with increased proliferation of breast cancer cells, mutations in breast cancer stem/progenitor cells subpopulations did not correlate with changes in metabolic gene expression. CONCLUSIONS: The adaptive capacity of breast cancer stem/progenitor cells may enable tumors to survive variable conditions encountered during progressive stages of cancer growth.