CD117 immunoexpression in oral and sinonasal mucosal melanoma does not correlate with somatic driver mutations in the MAPK pathway

BACKGROUND

Mutations on KIT and downstream genes of MAPK pathway that overstimulate cellular proliferation have been associated with primary oral and sinonasal melanomas (POSNM), but there is limited information that allows the use of personalized therapy. Thus, the aim of the present study was to determine a possible association between the C-KIT immunohistochemical expression with the presence of somatic driver mutations in NRAS, BRAF, KIT, MITF and PTEN on POSNM.

METHODS

A retrospective study included 62 tumour samples of an oncological reference centre in Mexico City (17-year period). Immunohistochemistry stain of C-KIT was carried out. Genomic DNA was obtained and used to assess hotspot mutations of KIT, NRAS, BRAF, MITF and PTEN through qPCR. Chi-square, Fisher's exact and the Mann-Whitney U tests were applied when necessary. The significance was set at P < 0.05.

RESULTS

Sixty-two cases were included, 74% were positive for C-KIT immunoexpression, all exhibited moderate/strong intensity. Ten (16.1%) samples harboured at least one mutation, 6.4% and 6.6% for NRAS^{Q 61R} and BRAF^{V 600E} , respectively, followed by KIT^K624E (3.2%). No KIT^{L 576P} , MITF or PTEN mutations were identified. No significant correlation was observed between mutations and immunostaining (rs = -0.057, P = 0.765).

CONCLUSIONS

Regardless of the high immunoexpression of C-KIT, there was no association with the MAPK mutations among POSNM samples. Thus, C-KIT immunohistochemistry is not a reliable tool to detect POSNM candidates for biological therapy.

A pharmacoeconomic analysis of the collection and preservation of samples in the biobank of the "Instituto Nacional de Cancerología" in Mexico City

In this work we estimated the budgetary impact of the samples produced by the biobank of the "Instituto Nacional de Cancerología" (BT-INCan) to set a recuperation fee from the perspective of the Health Ministry of Mexico. The study is an observational retrospective review of the direct medical costs (DMCs) of the processes involved in cryopreservation of the samples collected, on a per sample basis, including materials, laboratory tests, personnel, and administrative costs. Materials and labor costs were determined by information collected from the BT-INCan. DMCs were provided depending on the type of sample: plasma, tissue and biopsy; they were calculated according to the process required to preserve them. Sensitivity analysis was performed using bootstrap. Recuperation costs ranged from 130 to 155 USD. Costs were considered on a 5-year time frame for the maintenance per sample, which is the average time that a sample is kept in the BT-INCan. The cost analysis is perceived as an approximation to the most adequate recuperation fee per sample needed to guarantee the correct development of the BT-INCan. This work provides a basis and valuable information about costs, to enable several health institutions to strategically plan and manage a biobank or even motivate to establish their own biobank.

A microRNA signature associated with pathological complete response to novel neoadjuvant therapy regimen in triple-negative breast cancer

Neoadjuvant chemotherapy aims to improve the outcome of breast cancer patients, but only few would benefit from this treatment. Pathological complete response has been proposed as a surrogate marker for the prediction of long-term clinical benefits; however, 50%-85% patients have an unfavorable pathological complete response to chemotherapy. MicroRNAs are known biomarkers of breast cancer progression; nevertheless, their potential to identify patients with pathological complete response remains poorly understood. Here, we investigated whether a microRNA profile could be associated with pathological complete response in triple-negative breast cancer patients receiving 5-fluorouracil, adriamycin, cyclophosphamide-cisplatin/paclitaxel as a novel neoadjuvant chemotherapy. In the discovery cohort, the expression of 754 microRNAs was examined in tumors from 10 triple-negative breast cancer patients who achieved pathological complete response and 8 without pathological complete response using TaqMan Low-Density Arrays. Unsupervised hierarchical cluster analysis identified 11 microRNAs with significant differences between responder and no-responder patients (fold change ≥ 1.5; p < 0.05). The differential expression of miR-30a, miR-9-3p, miR-770, and miR-143-5p was validated in an independent group of 17 patients with or without pathological complete response. Moreover, Kaplan-Meier analysis showed that expression of these four microRNAs was associated with an increased disease-free survival. Gene ontology classification of predicted microRNA targets indicated that numerous genes are involved in pathways related to chemoresistance, such as vascular endothelial growth factor, focal adhesion kinase, WNT, ERbB, phosphoinositide 3-kinase, and AKT signaling. In summary, we identified a novel microRNA expression signature associated with pathological complete response in breast cancer. We propose that the four validated microRNAs could be used as molecular biomarkers of clinical response in triple-negative breast cancer patients with pathological complete response to neoadjuvant therapy.

Idiopathic granulomatous mastitis. Experience at a cancer center

BACKGROUND

Idiopathic granulomatous mastitis (IGM) is a benign breast disease that has been described as a rare granulomatous inflammation (GI). It can mimic inflammatory breast cancer.

MATERIAL AND METHODS

We included women with a diagnosis of IGM referred to an oncologic hospital between January 01, 2007 and to March 31, 2011, with diagnosis of breast cancer, in whom biopsy reported GI, without other cause related. The aim of this study was to review the clinical, radiologic and pathologic characteristics of a cohort of women with IGM.

RESULTS

We analyzed 58 patients; mean age was 38 ± 12 years. Mammography showed diffuse asymmetry (n = 19) and focal asymmetry (n = 13); breast ultrasound showed heterogeneous and hypoechoic areas (n = 28) and lumps (n = 21) as the most frequent lesions. All biopsies showed lobulocentric GI. Treatment included antibiotics (n = 20), steroids (n = 8), both treatments (n = 20), surgical excision (n = 3) and observation (n = 7). Forty-three patients (74%) had complete remission; mean time to remission was 9.5 ± 5.8 months. Fifteen (26%) had partial remission. Any patient had progression or relapse.

CONCLUSIONS

IGM is a benign breast condition that may mimic breast inflammatory cancer. Ultrasonography and mammography findings reveal characteristic data that can be useful for establishing the diagnosis; however, biopsy is the gold standard for its diagnosis and should be taken in any patient even with a mild suspicion of cancer.