Development of an International Virtual Multidisciplinary Tumor Board for Breast Cancer in Mongolia

INTRODUCTION

Breast cancer is the most diagnosed cancer among Mongolian women and mortality rates are high. We describe a virtual multi-institutional and multidisciplinary tumor board (MTB) for breast cancer created to assist the National Cancer Center of Mongolia.

MATERIALS AND METHODS

A virtual MTB for breast cancer was conducted with participation of two United States and 1 Mongolian cancer centers. A standardized template for presentations was developed. Recommendations were summarized and shared with participants. Collected data included patient demographics, tumor characteristics, stage, imaging and treatments performed, and recommendations. Questions were categorized as treatment, diagnosis, or palliative questions.

RESULTS

Fifteen patients were evaluated. Median age was 39 y. 86.7% of breast cancers were invasive ductal cancers and 13.3% were metaplastic carcinomas. 53.3% were estrogen and progesterone receptor positive (ER+/PR+), 60% were HER2+, 13.3% were triple negative, and 26.7% were recurrent. 40% of patients were evaluated with mammography. 6% received positron emission tomography scans for metastatic evaluation. 66.7% of surgical patients received neoadjuvant chemotherapy. Herceptin was administered to 55.6% of patients with Her2+ cancers. Modified radical mastectomy was most commonly performed and reconstruction was rare. Sentinel lymph node biopsy was not performed. 66.7% of ER+/PR+ patients received endocrine therapy. 6.7% of patients received radiation. 75% of MTB questions pertained to treatment. Recommendations were related to systemic therapy (40%), surgical management (33.3%), pathology (13.3%), and imaging (13.3%).

CONCLUSIONS

This study illustrates the development of an international, virtual, multi-institutional breast cancer MTB and provides insight into challenges and potential interventions to improve breast cancer care in Mongolia.

Medical Students' Perceptions of Clinical and Research Training: An International Needs Assessment of 26 Countries

Objective

Despite calls to incorporate research training into medical school curriculum, minimal research has been conducted to elucidate trends in research knowledge, opportunities, and involvement globally. This study aims to: (1) assess medical students' perceptions of the level of training they received on research based on their medical school training, and (2) evaluate the obstacles related to conducting research as part of medical students' training.

Methods

A 94-question, bilingual survey designed by a small focus group of individuals from medical schools across the globe and administered to medical students from different parts of the world, distributed via social media networks (Twitter, Now X, Facebook) and email distributions via international partnerships from November 1 to December 31, 2020. The survey collected demographic information including age, gender, medical institution and country, degree, year in training, clinical rotations completed, plans for specialization, and additional graduate degrees completed. Statistical analysis included a summary of survey participant characteristics, and a comparison between regions, with a variety of comparison and logistic regression models used.

Results

A total of 318 medical students from 26 countries successfully completed the survey. Respondents were majority female (60.1%), from Latin America (LA) (53.1%), North America (NA) (28.6%), and Other world regions (Other) (18.2%). Students felt research was an important component of medical training (87.7%), although many reported lacking research support from their institution (47.5%). There were several reported barriers to research, including lack of research opportunities (69.4%), lack of mentors (56.6%), lack of formal training (54.6%), and barriers due to the coronavirus disease 2019 (COVID-19) pandemic (49.3%). Less frequent were barriers related to financial resources (41.6%), physical resources (computer or internet access) (18%), and English language ability (6.9%). Students from Latin America and Other were more likely to report a desire to pursue research later in their medical careers compared with students from North America.

Conclusions and Implications for Translation

Despite significant interest in research, medical students globally report a lack of formal research training, opportunities, and several barriers to conducting research, including the COVID-19 pandemic. The study highlights the need for student research training internationally and the role of further regional-specific and institutional-specific evaluation of research training needs.

Oncologic Outcomes of Multi-Institutional Minimally Invasive Inguinal Lymph Node Dissection for Melanoma Compared with Open Inguinal Dissection in the Second Multicenter Selective Lymphadenectomy Trial (MSLT-II)

BACKGROUND

Minimally invasive inguinal lymphadenectomy (MILND) is safe and feasible, but limited data exist regarding oncologic outcomes.

METHODS

This study performed a multi-institutional retrospective cohort analysis of consecutive MILND performed for melanoma between January 2009 and June 2016. The open ILND (OILND) comparative cohort comprised patients enrolled in the second Multicenter Selective Lymphadenectomy Trial (MSLT-II) between December 2004 and March 2014.The pre-defined primary end point was the same-basin regional nodal recurrence, calculated using properties of binomial distribution. Time to events was calculated using the Kaplan-Meier method. The secondary end points were overall survival, progression-free survival, melanoma-specific survival (MSS), and distant metastasis-free survival (DMFS).

RESULTS

For all the patients undergoing MILND, the same-basin regional recurrence rate was 4.4 % (10/228; 95 % confidence interval [CI], 2.1-7.9 %): 8.2 % (4/49) for clinical nodal disease and 3.4 % (6/179) for patients with a positive sentinel lymph node (SLN) as the indication. For the 288 patients enrolled in MSLT-II who underwent OILND for a positive SLN, 17 (5.9 %) had regional node recurrence as their first event. After controlling for ulceration, positive LN count and positive non-SLNs at the time of lymphadenectomy, no difference in OS, PFS, MSS or DMFS was observed for patients with a positive SLN who underwent MILND versus OILND.

CONCLUSION

This large multi-institutional experience supports the oncologic safety of MILND for melanoma. The outcomes in this large multi-institutional experience of MILND compared favorably with those for an OILND population during similar periods, supporting the oncologic safety of MILND for melanoma.

Guiding principles for peptide nanotechnology through directed discovery

Life's diverse molecular functions are largely based on only a small number of highly conserved building blocks - the twenty canonical amino acids. These building blocks are chemically simple, but when they are organized in three-dimensional structures of tremendous complexity, new properties emerge. This review explores recent efforts in the directed discovery of functional nanoscale systems and materials based on these same amino acids, but that are not guided by copying or editing biological systems. The review summarises insights obtained using three complementary approaches of searching the sequence space to explore sequence-structure relationships for assembly, reactivity and complexation, namely: (i) strategic editing of short peptide sequences; (ii) computational approaches to predicting and comparing assembly behaviours; (iii) dynamic peptide libraries that explore the free energy landscape. These approaches give rise to guiding principles on controlling order/disorder, complexation and reactivity by peptide sequence design.

Molecular dynamics simulations reveal disruptive self-assembly in dynamic peptide libraries

There is significant interest in the use of unmodified self-assembling peptides as building blocks for functional, supramolecular biomaterials. Recently, dynamic peptide libraries (DPLs) have been proposed to select self-assembling materials from dynamically exchanging mixtures of dipeptide inputs in the presence of a nonspecific protease enzyme, where peptide sequences are selected and amplified based on their self-assembling tendencies. It was shown that the results of the DPL of mixed sequences (e.g. starting from a mixture of dileucine, L₂, and diphenylalanine, F₂) did not give the same outcome as the separate L₂ and F₂ libraries (which give rise to the formation of F₆ and L₆), implying that interactions between these sequences could disrupt the self-assembly. In this study, coarse grained molecular dynamics (CG-MD) simulations are used to understand the DPL results for F₂, L₂ and mixed libraries. CG-MD simulations demonstrate that interactions between precursors can cause the low formation yield of hexapeptides in the mixtures of dipeptides and show that this ability to disrupt is influenced by the concentration of the different species in the DPL. The disrupting self-assembly effect between the species in the DPL is an important effect to take into account in dynamic combinatorial chemistry as it affects the possible discovery of new materials. This work shows that combined computational and experimental screening can be used complementarily and in combination providing a powerful means to discover new supramolecular peptide nanostructures.

Using experimental and computational energy equilibration to understand hierarchical self-assembly of Fmoc-dipeptide amphiphiles

Despite progress, a fundamental understanding of the relationships between the molecular structure and self-assembly configuration of Fmoc-dipeptides is still in its infancy. In this work, we provide a combined experimental and computational approach that makes use of free energy equilibration of a number of related Fmoc-dipeptides to arrive at an atomistic model of Fmoc-threonine-phenylalanine-amide (Fmoc-TF-NH₂) which forms twisted fibres. By using dynamic peptide libraries where closely related dipeptide sequences are dynamically exchanged to eventually favour the formation of the thermodynamically most stable configuration, the relative importance of C-terminus modifications (amide versus methyl ester) and contributions of aliphatic versus aromatic amino acids (phenylalanine F vs. leucine L) is determined (F > L and NH₂ > OMe). The approach enables a comparative interpretation of spectroscopic data, which can then be used to aid the construction of the atomistic model of the most stable structure (Fmoc-TF-NH₂). The comparison of the relative stabilities of the models using molecular dynamic simulations and the correlation with experimental data using dynamic peptide libraries and a range of spectroscopy methods (FTIR, CD, fluorescence) allow for the determination of the nanostructure with atomistic resolution. The final model obtained through this process is able to reproduce the experimentally observed formation of intertwining fibres for Fmoc-TF-NH₂, providing information of the interactions involved in the hierarchical supramolecular self-assembly. The developed methodology and approach should be of general use for the characterization of supramolecular structures.

Elucidation of the bonding of a near infrared dye to hollow gold nanospheres - a chalcogen tripod

Determining how Raman labels orientate on the surface of HGNs to aid in future advancements of designing NIR nanosensors.

Infrared surface enhanced Raman scattering (SERS) is an attractive technique for the in situ detection of nanoprobes in biological samples due to the greater depth of penetration and reduced interference compared to SERS in the visible region. A key challenge is to understand the surface layer formed in suspension when a specific label is added to the SERS substrate in aqueous suspension. SERS taken at different wavelengths, theoretical calculations, and surface-selective sum frequency generation vibrational spectroscopy (SFG-VS) were used to define the surface orientation and manner of attachment of a new class of infrared SERS labels with a thiopyrylium core and four pendant 2-selenophenyl rings. Hollow gold nanospheres (HGNs) were used as the enhancing substrate and two distinct types of SERS spectra were obtained. With excitation close to resonance with both the near infrared electronic transition in the label (max 826 nm) and the plasmon resonance maximum (690 nm), surface enhanced resonance Raman scattering (SERRS) was obtained. SERRS indicates that the major axis of the core is near to perpendicular to the surface plane and SFG-VS obtained from a dried gold film gave a similar orientation with the major axis at an angle 64–85° from the surface plane. Longer excitation wavelengths give SERS with little or no molecular resonance contribution and new vibrations appeared with significant displacements between the thiopyrylium core and the pendant selenophene rings. Analysis using calculated spectra with one or two rings rotated indicates that two rings on one end are rotated towards the metal surface to give an arrangement of two selenium and one sulphur atoms directly facing the gold structure. The spectra, together with a space filled model, indicate that the molecule is strongly adsorbed to the surface through the selenium and sulphur atoms in an arrangement which will facilitate layer formation.

CHARMM force field parameterization protocol for self-assembling peptide amphiphiles: the Fmoc moiety

Aromatic peptide amphiphiles are known to self-assemble into nanostructures but the molecular level structure and the mechanism of formation of these nanostructures is not yet understood in detail.

Practically convenient and industrially-aligned methods for iridium-catalysed hydrogen isotope exchange processes

The use of alternative solvents in the iridium-catalysed hydrogen isotope exchange reaction with developing phosphine/NHC Ir(I) complexes has identified reaction media which are more widely applicable and industrially acceptable than the commonly employed chlorinated solvent, dichloromethane. Deuterium incorporation into a variety of substrates has proceeded to deliver high levels of labelling (and regioselectivity) in the presence of low catalyst loadings and over short reaction times. The preparative outputs have been complemented by DFT studies to explore ligand orientation, as well as solvent and substrate binding energies within the catalyst system.

Incorporating margin status information in treatment decisions for women with ductal carcinoma in situ: a decision analysis

To integrate margin status information into the decision to undergo radiation therapy (RT) following breast-conserving surgery (BCS) for women with ductal carcinoma in situ (DCIS). We developed a decision-analytic Markov model to project quality-adjusted life years (QALYs) for a hypothetical cohort of 55-year-old women with DCIS over a lifetime horizon treated with or without RT following BCS. We estimated the transition probabilities of local DCIS and invasive recurrences based on the margin status (free, close, or positive) from a systematic literature review. Other probability estimates and utilities were collected from the published literature. Using the conditions defined in this model, expected QALYs after BCS alone were better than those after BCS with RT under the free-margin scenario (15.72 vs. 15.58) and worse in the close-margin (15.44 vs. 15.50) and positive-margin scenarios (15.20 vs. 15.33). The probability of receiving a salvage mastectomy varied from 10 to 28%, depending on margin status and treatment. One-way sensitivity analyses showed that the optimal treatment was sensitive to patients' preferences and RT side effects. Probabilistic sensitivity analyses revealed that BCS alone would be the best strategy in 54% of the cases under the free-margin scenario, 48% under the close-margin scenario, and 44% under the positive-margin scenario. This study illustrates that margin status is able to provide supplementary information on the decision of DCIS treatment. Our analyses also highlight the importance of patients' preferences in decision making. Our findings suggest that RT is not necessary for all patients with DCIS undergoing BCS.

Management of the contralateral breast in women with breast cancer

Abstract #MS1-2

Patients with unilateral breast cancer are at increased risk for developing a second cancer in the contralateral breast. The annual risk of clinically detected metachronous contralateral breast cancer is about 0.7% Some women choose contralateral prophylactic mastectomy (CPM) to prevent cancer in the contralateral breast. A recently published study found that the use of CPM increased by 150% from 1998 to 2003 in the United States. Several studies have demonstrated that CPM significantly decreases the occurrence of contralateral breast cancer; the risk reduction is about 97%. Since the risk of systemic metastases often exceeds the risk of contralateral breast cancer, most patients will not experience any survival benefit from CPM. Moreover, CPM is not risk free, and patients may need to undergo additional surgical procedures, especially if reconstruction is performed. Nevertheless, most patients are satisfied with their decision to undergo CPM. Alternatives to CPM include close surveillance with clinical breast examination, mammography, and possibly breast magnetic resonance imaging. Endocrine therapy with tamoxifen or aromatase inhibitors significantly reduces the risk of contralateral breast cancer and may be more acceptable than CPM for some patients. Ovarian ablation and cytotoxic chemotherapy also reduce the risk of contralateral breast cancer. For women with unilateral breast cancer, management of the normal contralateral breast is complex. Future prospective studies are critically needed to evaluate the decision-making processes leading to CPM.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr MS1-2.

Validation of subareolar and periareolar injection techniques for breast sentinel lymph node biopsy

HYPOTHESIS

Subareolar or periareolar injection of radioactive technetium sulfur colloid is equivalent to other injection techniques for breast cancer sentinel lymph node (SLN) biopsy.

DESIGN AND SETTING

Prospective, multicenter clinical trial.

PATIENTS

A total of 3961 individuals with clinical stage I and II breast cancer.

INTERVENTIONS

All patients underwent attempted SLN biopsy followed by completion axillary dissection. Injection technique was determined by the preference of each participating surgeon. Most surgeons had little or no experience with SLN biopsy before participation in this study.

MAIN OUTCOME MEASURES

The SLN identification and false-negative rates.

RESULTS

An SLN biopsy was performed in 3961 patients using blue dye alone or radioactive colloid plus blue dye. Subareolar and periareolar radioactive colloid injection techniques were associated with SLN identification rates of 99.3% and 95.6%, respectively, with false-negative rates of 8.3% and 8.9%, respectively. The identification rates were significantly higher for these 2 techniques than for peritumoral injection of radioactive colloid (91.1%) or the use of blue dye alone (88.5%) (P<.001). The false-negative rates were similar for all techniques.

CONCLUSIONS

Although many medical centers have adopted subareolar and periareolar radioactive colloid injections because of their simplicity and convenience, a paucity of data from a few single-institutional studies has existed to substantiate the false-negative rates associated with these techniques. The results of this multicenter study establish the validity of subareolar and periareolar radioactive colloid injections and support the hypothesis that the lymphatic drainage of the entire breast is to the same few SLNs.

Frequency of sentinel lymph node metastases in patients with favorable breast cancer histologic subtypes

BACKGROUND

The need for axillary nodal staging in favorable histologic subtypes of breast cancer is controversial.

METHODS

Patients with clinical stage T1-2, N0 breast cancer were enrolled in a prospective, multi-institutional study. All patients underwent sentinel lymph node (SLN) biopsy followed by completion level I/II axillary dissection.

RESULTS

SLN were identified in 3,106 of 3,324 patients (93%). Axillary metastases were found in 35% and 40% of patients with infiltrating ductal carcinoma and infiltrating lobular carcinoma, respectively. Among tumor subtypes, positive nodes were found in 17% of patients with pure tubular carcinoma, 7% of patients with papillary cancer, 6% of patients with colloid (mucinous) carcinoma, 21% of patients with medullary carcinoma, and 8% of patients with DCIS with microinvasion.

CONCLUSIONS

Patients with favorable breast cancer subtypes have a significant rate of axillary nodal metastasis. Axillary nodal staging remains important in such patients; SLN biopsy is an ideal method to obtain this staging information.

Reliable lymphatic drainage to axillary sentinel lymph nodes regardless of tumor location within the breast

BACKGROUND

This analysis was performed in order to determine whether primary tumor location in breast cancer affects the axillary sentinel lymph node (SLN) identification (ID) rate, the false negative (FN) rate, incidence of axillary nodal metastases, or the number of SLN identified.

METHODS

In this prospective multi-institutional study, SLN biopsy was performed on clinical stage T1-2, N0 breast cancer patients using blue dye alone or in combination with radioactive colloid, followed by completion axillary LN dissection.

RESULTS

Central tumor location was associated with an improved FN rate, which may be related to reliable drainage from the subareolar lymphatic plexus. Tumor location did not significantly affect the SLN ID rate or the mean number of SLN identified. Medial tumor location was associated with a decreased rate of axillary nodal metastasis.

CONCLUSIONS

Breast cancers drain reliably to the axillary lymph nodes regardless of tumor location within the breast.

Comparison of the visually evoked response in drug-free chronic schizophrenic patients and normal controls

Thirteen cooperative male drug-free chronic schizophrenic patients, and 11 mentally normal male controls were studied. The VER was recorded from scalp leads O1, O2, Oz, C3 and C4 to combined ear reference (A1--A2). The stimulus was an unpatterned flash of single intensity. Compared to normal controls, there were no consistent differences in wave peak latencies or amplitudes for chronic schizophrenics in any brain area tested. When the chronic schizophrenic patients were separated on the basis of high and low tryptophan uptake, using the Frohman--Gottlieb criteria, the high uptake group exhibited normal VERs while in the occipital regions the low tryptophan uptake group exhibited prolonged latencies and an increased amplitude for wave V when compared to normals. From BPRS scores the high tryptophan subgroup indicated a greater degree of psychopathology than the low tryptophan subgroup. The results obtained do not support an indole hallucinogen hypothesis for process schizophrenia.