Correlation between breast cancer subtypes determined by immunohistochemistry and n-COUNTER PAM50 assay: a real-world study

PURPOSE

Molecular subtyping based on gene expression profiling (i.e., PAM50 assay) aids in determining the prognosis and treatment of breast cancer (BC), particularly in hormone receptor (HR)-positive/human epidermal growth factor receptor 2 (HER2)-negative tumors, where luminal A and B subtypes have different prognoses and treatments. Several surrogate classifications have been proposed for distinguishing between the luminal A and B subtypes. This study determines the accuracy of local immunohistochemistry (IHC) techniques for classifying HR-positive/HER2-negative (HR+/HER2-) tumors according to intrinsic subtypes using the nCOUNTER PAM50 assay as reference and the HR status definition according the ASCO/CAP recommendations.

METHODS

Molecular subtypes resulting from nCOUNTER PAM50 performed in our laboratory between 2014 and 2020 were correlated with three different proxy surrogates proposed in the literature based on ER, PR, HER2, and Ki67 expression with different cut-off values. Concordance was measured using the level of agreement and kappa statistics.

RESULTS

From 1049 samples with the nCOUNTER test, 679 and 350 were luminal A and B subtypes, respectively. Only a poor-to-fair correlation was observed between the three proxy surrogates and real genomic subtypes as determined by nCOUNTER PAM50. Moreover, 5-11% and 18-36% of the nCOUNTER PAM50 luminal B and A tumors were classified as luminal A and B, respectively, by these surrogates.

CONCLUSION

The concordance between luminal subtypes determined by three different IHC-based classifiers and the nCOUNTER PAM50 assay was suboptimal. Thus, a significant proportion of luminal A and B tumors as determined by the surrogate classifiers could be undertreated or over-treated.

Ribociclib-Related Stevens-Johnson Syndrome: Oncologic Awareness, Case Report, and Literature Review

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis belong to a severe dermatopathic spectrum that includes frequently fatal mucocutaneous manifestations consisting of whole epidermal necrosis and sloughing with bullous transformation, blistering, and further skin detachment. Notably, cancer patients are at higher risk of developing SJS than the general population as a consequence of both the nature of neoplastic disease and frequent exposure to anticancer drugs. Ribociclib is a newly approved cycline-dependent kinase inhibitor that has been recently associated with a single case of SJS. We hereby present a case of ribociclib-related SJS. Early detection of threatening skin lesions is crucial to permit the immediate discontinuation of ribociclib given the predictable and unacceptable risk level. In cases of established SJS, early aggressive support should be initiated, ribociclib should be abruptly discontinued, and specific treatment based on actual evidence should be started.

A Pilot, Phase II, Randomized, Open-Label Clinical Trial Comparing the Neurotoxicity of Three Dose Regimens of Nab-Paclitaxel to That of Solvent-Based Paclitaxel as the First-Line Treatment for Patients with Human Epidermal Growth Factor Receptor Type 2-Negative Metastatic Breast Cancer

BACKGROUND

This study aimed to characterize the neurotoxicity of three different regimens of nab-paclitaxel compared with a standard regimen of solvent-based (sb) paclitaxel for the first-line treatment of HER2-negative metastatic breast cancer based on the Total Neurotoxicity Score (TNS), a tool specifically developed to assess chemotherapy-induced neurotoxicity.

MATERIALS AND METHODS

This was a randomized, open-label study testing 4-week cycles of 80 mg/m² sb-paclitaxel (PACL80/w) on days 1, 8, and 15; 100 mg/m² nab-paclitaxel on days 1, 8, and 15 (NAB100/w); 150 mg/m² nab-paclitaxel on days 1, 8, and 15 (NAB150/w); and 150 mg/m² nab-paclitaxel on days 1 and 15 (NAB150/2w). In addition to the TNS, neuropathy was assessed using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE). Tumor response and quality of life were also evaluated.

RESULTS

Neurotoxicity, as evaluated by the TNS, did not significantly differ between the sb-paclitaxel group and any of the nab-paclitaxel groups. The frequency of (any grade) polyneuropathy, as measured by the NCI-CTCAE, was lower in the PACL80/w (n = 7, 50%) and NAB150/2w (n = 10, 62.5%) groups than in the NAB100/w (n = 13, 81.3%) or NAB150/w (n = 11, 78.6%) group. Although the differences were not statistically significant, compared with the other groups, in the NAB150/w group, the time to occurrence of grade ≥2 polyneuropathy was shorter, and the median time to recovery from grade ≥2 polyneuropathy was longer. Dose delays and reductions due to neurotoxicity and impact of neurotoxicity on the patients' experience of symptoms and functional limitations was greater with NAB150/w. Among the seven polymorphisms selected for genotyping, the variant alleles of EPHA5-rs7349683, EPHA6-rs301927, and EPHA8-rs209709 were associated with an increased risk of paclitaxel-induced neuropathy.

CONCLUSION

The results of this exploratory study showed that, regardless of the dose, nab-paclitaxel did not differ from sb-paclitaxel in terms of neurotoxicity as evaluated with the TNS. However, results from NCI-CTCAE, dose delays and reductions, and functional tools consistently indicate that NAB150/w regimen is associated with a greater risk of chemotherapy-induced neuropathy. Thus, our results question the superiority of the TNS over NCI-CTCAE for evaluating chemotherapy-induced neuropathy and guiding treatment decisions in this context. The selection of the nab-paclitaxel regimen should be individualized based on the clinical context and potentially supported by pharmacogenetic analysis. Registry: EudraCT, 2012-002361-36; NCT01763710 IMPLICATIONS FOR PRACTICE: The results of this study call into question the superiority of the Total Neurotoxicity Score over the National Cancer Institute Common Terminology Criteria for Adverse Events for evaluating chemotherapy-induced neuropathy and guiding treatment decisions in this context and suggest that a regimen of 150 mg/m² nab-paclitaxel administered on days 1, 8, and 15 is associated with a greater risk of chemotherapy-induced neuropathy and hematological toxicity compared with other lower-dose nab-paclitaxel regimens or a standard regimen of solvent-based paclitaxel. The selection of the nab-paclitaxel regimen should be individualized based on the clinical context and could benefit from pharmacogenetics analysis.

Use of bevacizumab as a first-line treatment for metastatic breast cancer

OBJECTIVE

During clinical practice, it can be challenging, given the lack of response biomarkers, to identify the patients with metastatic breast cancer (mbca) who would benefit most from the addition of bevacizumab to first-line standard chemotherapy. The aim of the present review was to summarize the relevant scientific evidence and to discuss the experience of a group of experts in using bevacizumab to treat mbca.

METHODS

A panel of 17 Spanish oncology experts met to discuss the literature and their experience in the use of bevacizumab as first-line treatment for mbca. During the meeting, discussions focused on three main issues: the profile of the patients who could benefit most from bevacizumab, the optimal bevacizumab treatment duration, and the safety profile of bevacizumab.

RESULTS

The subset of mbca patients who would benefit the most from the addition of bevacizumab to first-line standard chemotherapy are those with clinically defined aggressive disease. Treatment with bevacizumab should be maintained until disease progression or the appearance of unacceptable toxicity. In the mbca setting, the toxicity profile of bevacizumab is well known and can be managed in clinical practice after adequate training.

CONCLUSIONS

This expert group recommends administering bevacizumab as first-line treatment in patients with clinically aggressive disease.

Observational cross-sectional study to evaluate the prognostic factors influencing the selection of bevacizumab combined with chemotherapy in patients with HER2-negative metastatic breast cancer in routine clinical practice. ONCOSUR-AVALOX study

e11074

Background: Combining bevacizumab (BEV) with chemotherapy (CT) improves survival in HER2-negative metastatic breast cancer (MBC). We investigated the influence of age, ECOG, hormonal status, number of sites and location of metastases and patient decision on the selection of BEV combined with CT in MBC. Methods: Observational cross-sectional multicenter study in pts with HER2-negative MBC who have received first-line CT with BEV. Results: From November 2010 to November 2011, 124 pts were included: median age 51 (45-64) yr; ECOG: 0=50%; 60% pre-menopausic; 23% triple-negative (TN); 77% hormone receptor-positive (HR+). Metastatic disease: ≥3 sites=42% (TN: 32%; HR+: 45%); location: 44% bone, 35% lung, 30% liver. Most frequent BEV-based combinations were paclitaxel/BEV (53%) and docetaxel/BEV (14.5%); median no. of CT cycles: 6 (5-8). A disease-free survival (DFS) ≥12 months was achieved by 73%; TN: 68%; HR+: 76%. Overall response rate (ORR) was 58%: 51% partial response (PR), 7% complete response (CR); 28% stable disease (SD) and 10% disease progression. TN: ORR 44% (40% PR), clinical benefit 80% (36% SD); HR+: ORR 62% (54% PR), clinical benefit 87% (25% SD). 58% presented at least one toxicity, mainly grade 1-2; 26% BEV-related: only 3 (2.4%) grade 3 toxicities; no grade 4. Receiving adjuvant hormonal therapy was associated to DFS ≥12 months (p<0.05). ER+ tumors (OR: 0.215; 95% CI: 0.08-0.56; p=0.002) and one metastatic site, vs. ≥3 sites (OR: 0.309; 95% CI: 0.12-0.83; p=0,020) were independent factors associated with the selection of paclitaxel-BEV therapy in the overall population (TN or HR+). Metastases in the liver were significantly related to paclitaxel-BEV administration (p<0.01). Conclusions: Our findings suggest that first-line CT with BEV is an active and tolerable treatment option for pts with TN and HR+ MBC. ER+ tumors and a single metastatic site were identified as independent factors for the selection of a paclitaxel-BEV therapy. The presence of metastases in the liver was significantly associated to the administration of a paclitaxel-BEV regimen.

Left atrium myxosarcoma: an exceptional cardiac malignant primary tumor

We report the case of a 32-year-old patient with a left atrium myxosarcoma, presenting with congestive heart failure. It is a rare cardiac malignant primary tumor that seems to derive from the same cellular line as myxomas, but the prognosis is very different. These tumors present local recidives and distance metastasis, so the mean survival is about 1 year, independent of any therapeutical option.

Evaluation of the antitumor activity of interleukin-12 in an experimental murine model of colorectal cancer induced by 1,2 dimethyl-hydrazine (DMH)

OBJECTIVE

Interleukin 12 (IL-12) is a cytokine that may enhance the proliferation and cytotoxic activity of T lymphocytes and natural killer (NK) cells. A relationship between extensive intratumoral infiltration of NK cells and longer survival rates in colorectal cancer (CRC) patients was previously noted. Preliminary evidence suggests that the combined administration of IL-12 and IL-2 may produce additive immunomodulatory activity. The purpose of this study was to determine whether the systemic administration of IL-12 (+/- IL-2) may induce an immune response against CRC as induced by 1,2-dimethylhydrazine (DMH).

METHODS

Sixty-five 6-week-old Wistar rats were treated with weekly subcutaneous injections of DMH for 26 weeks at a dose of 20 mg/kg of body weight. Once tumoral induction was over, the animals were randomly allocated to one of three groups: I, control; II, intraperitoneal injections of IL-12; III, intraperitoneal injections of IL-12 combined with IL-2. At 30 weeks, all surviving animals were sacrificed. We studied the following parameters in each rat--number of tumors, size of tumors, and total tumoral volume. Tumor samples were studied using the monoclonal antibody CD 57 for the detection of NK cells. The extent of NK infiltration was classified as small, less than 50 NK cells/50 high-power field (HPF); moderate, 50 to 150 NK cells/50 HPF, and extensive, more than 150 NK cells/50 HPF.

RESULTS

Thirty-five rats died before completion of the carcinogen exposure, and 30 rats were randomized (10 each group). In group II, 2 animals died during treatment. All rats in groups I and III developed tumors, while in group II two rats (25%) were tumor-free. Moreover, only one rat in group II developed multiple neoplasms, in contrast with group I and group III, where six rats (60%) and seven rats (70%), respectively, had more than one tumor. We found statistically significant differences in the mean number of tumors found in group II when compared to group I (p = 0.028) and group III (p = 0.019). Other parameters measured, such as biggest tumor size and total tumoral volume were found to be lower in group II, although no statistical differences were found between groups. Only 10% of rats in group I showed moderated/extensive NK cell infiltration, vs. 60% of rats in group II (p = 0.077) and 70% in group III (p = 0.02).

CONCLUSION

The administration of DMH to rodents provides a reliable and consistent means of inducing CRC that may be suitable for the evaluation of anti-cancer therapies. Our findings suggest that IL-12 is effective against the development of experimental CRC. Its antineoplastic effect could be attributed to the stimulus of this cytokine on the intratumoral infiltration of NK cells.