Survival and prognostic factors in adult medulloblastoma: the Salah Azaiz Institute experience

BACKGROUND

Medulloblastoma is the most common malignant brain tumor in children. This entity in adulthood is rare. The aim of our study is to evaluate therapeutic results and prognostic factors of adult medulloblastoma treated at our institute with post-operative radiotherapy.

METHODS

We retrospectively reviewed a cohort of 55 patients with medulloblastoma who underwent radiation in the department of radiation oncology of institute Salah Azaiz (Tunis) over a 18-year period (1994-2012).

RESULTS

The surgery was total or subtotal resection in 73% of cases. Forty-eight patients received radiotherapy to the entire craniospinal axis as part of the curative treatment. The median interval from surgery to the initiation of radiotherapy was 83 days. Etoposide-cisplatin chemotherapy was only performed in metastatic patients (n = 4). The 5-years and 10-years overall survival rates were respectively 53 and 34%. The dose of radiotherapy to the craniospinal axis was a prognostic factor. The 5-years and 10-years event-free-survival rates were 64 and 41%. Reduction in the dose of radiotherapy to the craniospinal axis and fourth ventricular floor involvement were correlated with a worse event-free survival.

CONCLUSION

Our results, compared to those of the literature, conclude that the reduction in the dose of radiotherapy to the craniospinal axis (<34 Gy) in the standard risk group of adult medulloblastoma could not be done without chemotherapy. In the high-risk group of adult medulloblastoma, radiotherapy to the cerebrospinal axis at the dose of 36 Gy with chemotherapy, is required for disease control.

Effect of Gamma Irradiation on Pathogenic Staphylococcus aureus in Packaged Ready-to-Eat Salads Treated with Biological Extracts

Providing pathogen-free ready-to-eat (RTE) salads is critical for all consumers, especially individuals with weakened immunity. In this study, the efficacy of γ-irradiation on Staphylococcus aureus (S. aureus) in freshly packaged salads (4.24 log CFU/g) treated with essential oil (EO) and myrtle juice during 10 days of storage and their impact on organoleptic properties were investigated. EO was extracted by hydrodistillation and the chemical composition was analyzed by gas chromatography with Flame Ionization Detector (GC/FID) and gas chromatography/mass spectrometry (GC/MS). Myrtle juice was prepared from fresh fruits. The cytotoxic effects of Thymus capitatus (T. capitatus) EO against a normal human umbilical vein endothelial cell (HUVEC) were assessed. GC/FID and GC-MS analysis of the thyme EO revealed the presence of 13 compounds, including carvacrol (79.55%) and p-cymene (7.93%) as major components. The EO was found to be noncytotoxic, with concentrations lower than 0.16 µL/mL. A reduction of more than 3 log CFU/g and a total inactivation of S. aureus were achieved with the combination of gamma irradiation at 0.5 kGy with myrtle juice at 6 µL/mL and EO at 0.08 µL/mL, respectively. The treatment of fresh RTE salads with thyme and myrtle juice was evaluated as acceptable by the sensory panel. The combined effect showed a synergistic potential on the inactivation of S. aureus.

Symptomatic Posttreatment Edema after Stereotactic Radiotherapy for Intracranial Meningiomas: Patterns and Predictive Factors

PURPOSE/OBJECTIVE(S)

Symptomatic posttreatment edema (SPTE) is a complication that may develop after radiotherapy for intracranial meningiomas. Our study aims at reviewing rates of SPTE in a large cohort of a single institution and identifying possible predictive factors.

MATERIALS/METHODS

We retrospectively analyzed data of 293 patients with 304 intracranial meningiomas irradiated at our institution between 2005 and 2018. We evaluated rates of SPTE and investigated numerous factors by univariate and multivariate analysis. Kaplan Meier analysis was used for estimation of actuarial local control and overall survival.

RESULTS

Median age was 60 years. Meningiomas were treated with fractionated stereotactic radiation therapy (70%), single fraction stereotactic radiosurgery (24%) or fractionated stereotactic radiosurgery (6%). Median imaging follow-up was 60 months, actuarial 10-year local control rate for patients with grade 1 meningiomas who received radiotherapy as definitive treatment was 99%. Local control at 5 years was 94% for grade 1 meningioma, 57% and 53% for grade 2 and 3 respectively. Sixteen patients (5.5%) developed SPTE, median time to onset was 3 months (range, 1-26 months). On univariate analysis, age > 60 years (p > 0.03), pre-treatment peritumoral edema (p = 0.014), medline location (p = 0.018), tumor size > 30 mm (p = 0.015) and grade 2 histology (p = 0.03) were predictive of SPTE. On multivariate analysis, only tumor location and size remained statistically significant.

CONCLUSION

Based on our results, patients at high risk of SPTE can be identified based on patient and tumor characteristics. The best treatment technique in high-risk patients is yet to be defined.

Hypofractionated radiotherapy after breast-conserving surgery: Clinical and dosimetric factors predictive of acute skin toxicity

PURPOSE

The purpose of this study was to evaluate acute skin toxicity in early breast cancer patients treated with hypofractionated radiotherapy (HFRT) after breast-conserving surgery and to identify factors predictive for grade ≥ 2 acute skin toxicity.

MATERIALS AND METHODS

A monocentric retrospective study was carried out using cases treated between December 2017 and November 2020. We analyzed data from 202 patients with early breast cancer treated with 3D hypofractionated RT (40.05 Gy in 15 fractions) to the whole breast with or without regional lymph nodes, followed by 13.35 Gy in 5 fractions to the tumor bed. Acute skin toxicity was monitored during RT according to CTCAE (common toxicity criteria for adverse events) scale. Univariate and multivariate analyses were performed to assess predictive factors of acute skin toxicity.

RESULTS

Overall, there was no erythema in 9%, grade 1 erythema in 64.5%, grade 2 in 24%, and grade 3 in 2.5%. No grade 4 erythema was seen. Median delay between RT initiating and maximum skin reaction was 22 days (range 4-44 days). No patient interrupted treatment. In univariate analysis, the rate of acute skin toxicity grade 2---3 (G2-3) was significantly higher for patients with larger tumor size (p = 0.02), body mass index > 27 (p = 0.04), and time between chemotherapy (CT) and RT less than 20 days (p = 0.01). Dosimetric risk factors for acute skin toxicity G2‑3 were breast volume > 800 cc (p = 0.000), boost volume > 18 cc (p = 0.002), V105% > 40 cc (p = 0.03), and Dmax > 56 Gy (p = 0.007). CT, trastuzumab, regional lymph node radiation, and age were not correlated with increased skin toxicity. In multivariate analysis, acute skin toxicity correlated with T stage (p = 0.032), breast volume > 800 cc (p = 0.012), boost volume > 18 cc (p = 0.04), and Dmax > 56 Gy (p = 0.035).

CONCLUSION

Our results confirm that whole breast with or without lymph nodes hypofractionated RT is safe and well tolerated. The factors strongly associated with a decreased risk of G2‑3 skin toxicity are T1, breast volume < 800 c, boost volume < 18 cc, and Dmax < 56 Gy. Long-term follow-up is needed to evaluate late toxicity.

MARCKS as a Potential Therapeutic Target in Inflammatory Breast Cancer

Inflammatory breast cancer (IBC) is the most pro-metastatic form of breast cancer (BC). We previously demonstrated that protein overexpression of Myristoylated Alanine-Rich C Kinase Substrate (MARCKS) protein was associated with shorter survival in IBC patients. MARCKS has been associated with the PI3K/AKT pathway. MARCKS inhibitors are in development. Our objective was to investigate MARCKS, expressed preferentially in IBC that non-IBC (nIBC), as a novel potential therapeutic target for IBC. The biologic activity of MPS, a MARCKS peptide inhibitor, on cell proliferation, migration, invasion, and mammosphere formation was evaluated in IBC (SUM149 and SUM190) and nIBC (MDA-MB-231 and MCF7) cell lines, as well as its effects on protein expression in the PTEN/AKT and MAPK pathways. The prognostic relevance of MARCKS and phosphatase and tensin homolog (PTEN) protein expression as a surrogate marker of metastasis-free survival (MFS) was evaluated by immunohistochemistry (IHC) in a retrospective series of archival tumor samples derived from 180 IBC patients and 355 nIBC patients. In vitro MPS impaired cell proliferation, migration and invasion, and mammosphere formation in IBC cells. MARCKS inhibition upregulated PTEN and downregulated pAKT and pMAPK expression in IBC cells, but not in nIBC cells. By IHC, MARCKS expression and PTEN expression were negatively correlated in IBC samples and were associated with shorter MFS and longer MFS, respectively, in multivariate analysis. The combination of MARCKS-/PTEN+ protein status was associated with longer MFS in IBC patient only (p = 8.7 × 10⁻³), and mirrored the molecular profile (MARCKS-downregulated/PTEN-upregulated) of MPS-treated IBC cell lines. In conclusion, our results uncover a functional role of MARCKS implicated in IBC aggressiveness. Associated with the good-prognosis value of the MARCKS-/PTEN+ protein status that mirrors the molecular profile of MPS-treated IBC cell lines, our results suggest that MARCKS could be a potential therapeutic target in patients with MARCKS-positive IBC. Future preclinical studies using a larger panel of IBC cell lines, animal models and analysis of a larger series of clinical samples are warranted in order to validate our results.

Trabectedin (Yondelis®) as a Therapeutic Option in Gynecological Cancers: A Focus on its Mechanisms of Action, Clinical Activity and Genomic Predictors of Drug Response

The use of predictive biomarkers provides potential individualized cancer therapeutic options to prevent therapy failure as well as serious toxicities. Several recent studies showed that predictive and prognostic biomarkers are a notable personalized strategy to improve patients' care in several cancers. Trabectedin (Yondelis®) is a cytotoxic agent, derived from a marine organism, harbouring a significant antitumor activity against several cancers such as soft tissue sarcoma, ovarian, and breast cancers. Recently and with the advent of molecular genetic testing, BRCA mutational status was found as an important predictor of response to this anticancer drug, especially in gynecological cancers. The aim of this updated review is to discuss the mechanisms of action of trabectedin against the wellknown cancer hallmarks described until today. The current advances were also examined related to genomic biomarkers that can be used in the future to predict the efficacy of this potent anticancer natural molecule in various gynecological cancers.

Inflammatory Breast Cancer: Clinical Characteristics and Influence of Molecular Subtypes on Treatment Response

Introduction:

Inflammatory Breast Cancer (IBC) is a rare and very aggressive breast cancer with poor prognosis. The prevalence is different from a country to another. In Tunisia, it is about 5 to 7% of breast cancer. The aim of this study is to describe the epidemiological and histopathological features of patients with inflammatory breast cancer and to evaluate the treatment response according to the molecular subtypes.

Methods:

This retrospective review identified 31 patients with no metastatic IBC treated in our radiotherapy department between December 2019 and November 2020. IBC was confirmed using the clinical criteria. Baseline clinic-pathological and treatment information was retrieved from medical records. Statistical analysis was performed with IBM SPSS V.20.

Results:

Median age was 51.3 years [27-68]. 48% of tumors were grade 3. The average tumor size was 36mm [10-90]. The histological type was ductal carcinoma in 97%. Vascular invasion was noted in 24 patients (77%). Thirty patients were classified as stage IIIB and one patient was IIIC. 74% were hormone receptor positive and 45% were HER2 positive. Luminal B was the predominant subtype (52%) followed by Her2 positive (32%), Luminal A (23%), and triple negative (3%) All patients had chemotherapy: neoadjuvant for 26 patients (84%) and adjuvant for 5 patients (16%). Nine patients (29%) had tumor pathological complete response (pCR). Partial response was observed in 18 patients (58%). Lymph node pCR was noted in 16% of cases (n=5). Endocrine therapy and trastuzumab were given to 76% and 45% of patients, respectively. The influence of the molecular subtype was not statistically significant on the response to neoadjuvant treatment. The highest rate of pCR were 43% for Her2positive, then 27%, 21% and 9% for Luminal B, Luminal A and Triple negative, respectively (p=0.2).

Conclusion:

Our study showed a high percentage of hormone receptor and Her2+ (74% and 45% respectively) in IBC. Luminal B was the most frequent subtype. Anthracycline-based chemotherapy and trastuzumab improved the pCR rate: 44% for Her2positive. Triple negative showed poorer pCR than other breast cancer subtype without a significant difference. A larger study is warranted to confirm our findings.

Lebecetin, a snake venom C-type lectin protein, modulates LPS-induced inflammatory cytokine production in human THP-1-derived macrophages

The excessive production of inflammatory mediators results in an overactive immune response leading to the worsening of various human diseases. Thus, there is a still need to identify molecules able to regulate the inflammatory response. Lebecetin, a C-type lectin protein isolated from Macrovipera lebetina snake venom, was previously characterized as a platelet aggregation inhibitor and antitumor active biomolecule. In the present work, we investigated its effect on the production of some cytokines linked to inflammatory response and the underlying mechanisms in lipopolysaccharide (LPS)-induced THP1 macrophages. Interestingly, we found that lebecetin reduced the levels of the pro-inflammatory cytokines TNF-α, IL-6, and IL-8 while it partially increased LPS-induced secretion of the immunomodulatory cytokine IL-10. Furthermore, this modulatory effect was accompanied by decreased activation of ERK1/2, p38, AKT kinases and NF-κB along with reduced expression of αvβ3 integrin. Thus, this study highlights the promising role of lebecetin as a natural biomolecule that could manage the inflammatory response involved in the development and progression of inflammatory diseases.