Preoperative chemotherapy for operable breast cancer

Potential association factors for developing effective peptide-based cancer vaccines

Peptide-based cancer vaccines have been shown to boost immune systems to kill tumor cells in cancer patients. However, designing an effective T cell epitope peptide-based cancer vaccine still remains a challenge and is a major hurdle for the application of cancer vaccines. In this study, we constructed for the first time a library of peptide-based cancer vaccines and their clinical attributes, named CancerVaccine (https://peptidecancervaccine.weebly.com/). To investigate the association factors that influence the effectiveness of cancer vaccines, these peptide-based cancer vaccines were classified into high (HCR) and low (LCR) clinical responses based on their clinical efficacy. Our study highlights that modified peptides derived from artificially modified proteins are suitable as cancer vaccines, especially for melanoma. It may be possible to advance cancer vaccines by screening for HLA class II affinity peptides may be an effective therapeutic strategy. In addition, the treatment regimen has the potential to influence the clinical response of a cancer vaccine, and Montanide ISA-51 might be an effective adjuvant. Finally, we constructed a high sensitivity and specificity machine learning model to assist in designing peptide-based cancer vaccines capable of providing high clinical responses. Together, our findings illustrate that a high clinical response following peptide-based cancer vaccination is correlated with the right type of peptide, the appropriate adjuvant, and a matched HLA allele, as well as an appropriate treatment regimen. This study would allow for enhanced development of cancer vaccines.

Tumor dormancy and metastasis

Metastasis--the spread of cancer to distant organs--is responsible for most cancer deaths. Current adjuvant therapy is based on prognostic indicators that stratify patients into defined risk groups. However, some patients believed to have a good prognosis nonetheless develop metastases, in some cases many years after apparently successful treatment of their primary cancer. This period of clinical dormancy leads to many questions about how best to manage patients, including how to better assign risk of late recurrence, how long to monitor patients, and whether some patients will benefit from extended therapy to prevent late recurrences. The development of targeted therapies with fewer side effects is leading to clinical trials aimed at determining the effectiveness of such long-term therapy. However, much remains to be learned about tumor dormancy. Experimental studies are shedding light on biological and molecular mechanisms potentially responsible for tumor dormancy. Emerging research into tumor initiating cells, immunotherapy, and metastasis suppressor genes, may lead to new approaches for targeted antimetastatic therapy to prolong tumor dormancy. An improved understanding of tumor dormancy is needed for better management of patients at risk for late-developing metastases.

Avoidance of axillary lymph node dissection in selected patients with node-positive breast cancer

AIMS

Currently, it is standard practice to avoid ALND in patients with negative SLN, whereas this procedure is mandated for those with positive SLN. However, there has been some debate regarding the necessity of complete ALND in all patients with positive SLN. This review article discusses the issues related to eliminating the need for ALND in selected patients with positive nodes.

METHODS

A review of the English language medical literature was performed using the MEDLINE database and cross-referencing major articles on the subject, focusing on the last 10 years.

RESULTS

Currently, complete ALND is mandated in patients with SLN macrometastases as well as those with clinically positive nodes. It is not clear whether SLN biopsy is appropriate for axillary staging in patients with initially clinically positive nodes (N1) that become clinically node-negative (N0) after neoadjuvant chemotherapy. Although there is debate regarding whether ALND should be performed in patients with micrometastases in the SLN, it seems premature to abandon ALND in clinical practice. Moreover, it remains unclear whether it is appropriate to avoid complete ALND in patients with ITC-positive SLN alone.

CONCLUSIONS

In the absence of data from randomised trials, the long-term impact of SLN biopsy alone on axillary recurrence and survival rate in patients with SLN micrometastases as well as those with ITC-positive SLN remains uncertain. These important issues must be determined by careful analysis of the results of ongoing clinical trials.

Sentinel lymph node biopsy progress in surgical treatment of cancer

BACKGROUND

Forty-three years after the first description of the sentinel lymph node technique in malignant tumours of the parotid by Gould, sentinel lymph node biopsy (SNLB) has become a precious tool in the treatment of solid tumours.

METHODS

In the following review we give a synopsis of the fundamentals of the sentinel lymph node concept and then proceed to an overview of recent advances of SNLB in gastrointestinal cancers.

RESULTS

In some tumour entities, SNLB has been shown to reflect reliably the lymph node status of the tumour-draining lymph node basin. In melanoma and breast cancer, it became a widely accepted element of the routine surgical management of these malignant diseases. In gastrointestinal tumours, the technique is currently under intense investigation. First reports on its application in other solid tumours, such as non-small cell lung cancer, thyroid carcinoma, oropharyngeal carcinoma, vulvar carcinoma, and Merckel cell carcinoma of the skin, were published more recently.

CONCLUSION

SNLB has become an important component of diagnosis and treatment of solid tumours. A growing number of publications on SNLB in gastrointestinal cancer documents the interest of many investigators in the application of this technique in this tumour entity. As long as imaging techniques like 18FDG PET or other molecular imaging techniques are limited by their spatial resolution, SNLB remains the technique of choice for lympho-nodal staging.

Preoperative evaluation of prognosis in breast cancer patients by [(18)F]2-Deoxy-2-fluoro-D-glucose-positron emission tomography

PURPOSE

[18F]2-Deoxy-2-fluoro-D-glucose (FDG)-positron emission tomography (PET) was applied to breast cancer patients for the purpose of preoperative evaluation of patient prognosis with more accuracy than conventional TNM staging.

METHODS

FDG-PET was performed preoperatively in 81 patients with breast cancer, and the maximum standardized uptake value (SUVmax) of tumors as well as the focal accumulation of FDG in the axillary region (PET-N status) were investigated in their association with patient prognosis.

RESULTS

The SUVmax high group (n=40) showed a significantly (P=0.011) poorer prognosis than the SUVmax low group (n=41) (5-year disease-free survival (DFS) rates; 75.0% vs 95.1%). FDG-PET was more accurate in the diagnosis of axillary lymph node status than physical examination, i.e., diagnostic accuracy was 80% and 70% for FDG-PET and physical examination, respectively. The combination of high SUVmax and positive PET-N (+) was shown to be a highly significant risk factor being independent of the clinical T and N factors, i.e., patients with high SUVmax and positive PET-N (+) showed a significantly (P<0.001) poorer prognosis than the other patients (5-year DFS rates; 44.4% vs 96.8%).

CONCLUSIONS

These results suggest that FDG-PET is useful in the preoperative evaluation of prognosis in breast cancer patients with more accuracy than conventional TNM staging. It is expected that the indication of neoadjuvant chemotherapy can be decided more precisely by the preoperative evaluation of patient prognosis with FDG-PET due to a possible elimination of overtreatment for those who have good prognosis and, thus, need not to be treated with chemotherapy.

Current controversies in sentinel lymph node biopsy for breast cancer

Despite the widespread use of sentinel lymph node biopsy (SLNBx) in the surgical management of breast cancer patients, several areas remain controversial. The following controversies are reviewed: Learning curves and validation studies. There clearly is a learning curve, and a completion ALND should be done until adequate proficiency is exhibited, both in terms of identification and false-negative rates. Location of injection. Intradermal injection offers superior identification rates compared with peritumoral injection, with comparable false-negative rates. Subareolar injection is as accurate as peritumoral injection. The value of scintigraphy. Routine scintigraphy does not enhance identification or false-negative rates. Mapping agents. Blue dye and radioactive tracer combined to provide a higher identification rate than either used alone.SLNBx in DCIS. In patients with a high risk of microinvasion, such as large tumors, a mass or high-grade DCIS-SLNBx is justified.SLNBx following neoadjuvant chemotherapy. Although there is evidence that SLNBx after neoadjuvant chemotherapy may be accurate, these data should be applied cautiously. Implications of non axillary SLN, especially internal mammary nodes. Data do not support routine resection of internal mammary sentinel lymph nodes outside a clinical trial. Implications of micrometastases in the sentinel lymph node seen only on immunohistochemistry. Since the significance of such metastases is unclear, decisions regarding treatment of these patients should be individualized. The value of completion axillary lymph node dissection. Is being addressed in clinical trials. Until those studies mature, completion ALND should be performed for patients with SLN metastases, but may be abandoned for patients with a negative SLN.