e12579 Background: Metaplastic breast carcinoma is a rare histological subtype that has basal like characteristics and is reported to have a poorer prognosis than no specific type/ductal carcinoma (ductal/NST). We aimed to investigate clinicopathological features and outcome from a single institution based registry. Methods: Clinical records of breast cancer patients treated during 2012-2019 were screened and 31 cases of metaplastic breast carcinoma were found. Descriptive analysis was done for patients’ demographics and clinicopathological features. Kaplan Meier method was used to assess survival outcomes. Results: The incidence of metaplastic breast cancer was 0.5% (31/6180) in our study out of which the most common histopathological differentiation was squamous (45.16%). The second most common was sarcomatoid histology (32.25%), followed by chondroid (9.68%) and mixed histology (12.9%). The median age at diagnosis was 60 years ranging from 28 to 82 years. 64.15% of patients were post-menopausal. At presentation, three (9.67%) patients had metastatic disease while the rest were diagnosed with early (51.61%) and locally advanced cancers (38.72%). Triple negative cancers (ER/PR/Her2 negative) constituted the vast majority with 22 cases (80.6%) while hormone receptor positive (ER/PR positive, Her-2 negative) and Her-2 neu positive (ER/PR negative) made up the rest with three patients (9.67%) each group respectively. The median overall survival was found to be 39 months (95% CI 25.46 - 52.53). Conclusions: After a thorough search in PubMed and Google Scholar, we could not find a larger case series from India with clinical outcomes for metaplastic breast carcinoma. Our results suggest that metaplastic breast carcinoma is a heterogenous disease. Outcomes of metaplastic breast carcinoma are relatively worse when compared with literature for triple negative breast cancer and breast cancer in general. Further biological understanding may offer valuable insights for newer targets and therapeutic approaches to metaplastic breast cancer.

Background. Induction docetaxel, cisplatin, and 5-fluorouracil (TPF) chemotherapy followed by definitive concurrent chemoradiation remains the standard of care in locally advanced squamous cell carcinoma of head and neck cancers despite which the survival remains low. So, we analyzed the efficacy and adverse effect profile of the addition of nimotuzumab to standard TPF induction chemotherapy. Methods. We included 20 patients with locally advanced squamous cell carcinoma of the head and neck. Patients were administered with induction chemotherapy with nimotuzumab plus docetaxel, cisplatin, and 5-fluorouracil (TPF + N) followed by definitive concurrent chemoradiation with carboplatin. Treatment responses were assessed by PET-CT following induction chemotherapy and concurrent chemoradiation. Response rates, survival, and adverse effects data were tabulated and analyzed using the Kaplan Meier method. Results. At a minimum follow-up of two years, the median progression-free survival (PFS) and median overall survival (OS) were 16 months and 38 months, respectively. PFS and OS were not reached (NR) in patients who showed a complete radiological response (CR). Median PFS and OS in patients who had partial response were 17.6 and 34.5 months, respectively. All subsites of primary including oral cavity, hypopharynx, and oropharynx showed similar response rates and survival. Overall the treatment was well tolerated with predominantly grade 1/2 toxicities. Conclusions. Patients with locally advanced head and neck cancer could possibly have a better response and survival with nimotuzumab added to the standard TPF regimen. A complete response may serve as a good surrogate for survival irrespective of the primary site of head and neck cancer.

Objectives: 1) To correlate the methylation status of the O-6-methylguanine-DNA-methyltransferase (MGMT promoter gene) and response to alkylating agent-based treatment in high-grade gliomas. Background: The MGMT gene is epigenetically silenced by promoter hypermethylation in gliomas and this modification has emerged as a relevant predictor of therapeutic response. Methods: 20 cases of high-grade glioma were analyzed for MGMT promoter methylation by methylation-specific PCR. Response to treatment and overall survival data were recorded and data analysed. Results: MGMT promoter methylation was found in 60% of gliomas by methylation-specific PCR. The mean survival time of glioblastoma patients submitted to adjuvant therapy was significantly higher among patients with MGMT promoter methylation (P = 0.035) and methylation status was an independent predictive factor that was associated with improved prognosis. Discussion and Conclusion: MGMT promoter methylation status was a more reliable predictor of response to adjuvant therapy and prognosis of high-grade gliomas. A subset of patients received irinotecan and bevacizumab in the second line setting and patients with unmethylated MGMT seemed to do better than the MGMT promoter methylated group.

e12570 Background: Gene expression profiling for breast cancer has classified ER positive subtype into luminal A and luminal B. Luminal B breast cancer (LBBC) have a higher proliferation and poorer prognosis than luminal A tumors. Ki-67 index is the commonly used proliferation marker in breast cancer; however Ki67 expression can also be used to identify a subset of patients among LB with a favorable prognosis. This study attempts to verify this subset of LBBC patients based on DFS and PFS in non-metastatic and metastatic patients respectively. Methods: We retrospectively analyzed 80 IDC breast cancer patients diagnosed in 2013-2016 with complete follow-up till January-2021. We defined LBBC as ER+, PR+ or PR- , HER2+ or HER2- with a Ki67 index >20%. PFS was considered as the endpoint in patients presenting with metastatic disease whereas DFS was used in non-metastatic disease. The cut-off for ki67 was calculated using an X-tile plot (version 3.6.1, Yale University) by dividing Ki67 data into two populations: low and high, with randomized 1:1 “training” and “validation” cohorts. Results: Median age was 51.5 years. 18.7% (n=15) presented with metastasis at the time of diagnosis and their overall median PFS was found to be 25.8 months. The incidence of HER2 positive LBBC was found to be 15% (n=12) and none of them were found to be presented with metastasis. Survival and frequency of various sub groups in our study are enlisted in the given table. We estimated a Ki67 cut-off of 30% in patients with upfront metastatic disease and PFS was found to be higher in <30% compared to a Ki67 index >30% (38.9 months vs 19.7 months, p-0.002). Overall median DFS was not achieved in non-metastatic group (Mean DFS: 64.7 months) where as a statistically significant difference was observed in the survival of HER2 positive (median DFS: 53.5 months, mean DFS: 50.9) than HER2 negative patients (median DFS not achieved, mean: 66.97 months) ( p-0.021). We obtained a Ki67 cut-off of 32% in non- metastatic group and mean DFS was found to be higher in Ki67<32% (69 months) compared to Ki67>32% (61.4 months), however it failed to exhibit a statistically significant relationship ( p-0.373). Conclusions: Our study indicates that a subset of patients exists within metastatic and non-metastatic LBBC with differing prognosis based on Ki67. Larger studies are further required to confirm the findings and therapeutic implications.[Table: see text]

e15522 Background: Taxanes are an integral part of chemotherapy for a broad range of tumor types. The usual toxicities associated with Taxane use are peripheral neuropathy, myelosuppression and musculoskeletal adverse effects. Very few studies have reported taxane induced pulmonary toxicity objectively. In our study we explored Taxane induced pulmonary toxicity based on discrete CT findings. Methods: 40 non-smokers diagnosed with Her-2 negative breast cancer who received Taxane monotherapy from 2017 to 2018 were retrospectively analyzed for pre and post therapy CT changes. Following CT findings were considered significant as pulmonary toxicity; (a) Nonspecific area with ground-glass attenuation, (b) multifocal areas of airspace consolidation, (c) patchy distribution of ground-glass attenuation accompanied by interlobular septal thickening and (d) extensive bilateral ground-glass attenuation or airspace consolidations with traction bronchiectasis. The CT findings were assessed independently by two radiologists and one pulmonologist. Results: Our study showed that 5 patients (12.5%) developed pulmonary changes on chest CT post Taxane therapy as summarized in Table. Conclusions: Our study shows that taxane has more potential to induce pulmonary toxicity than reported in present literature. Given that taxanes are the most widely used chemotherapy, it is of utmost necessity to be cognizant of this under-reported potentially fatal adverse effect in a large population. Further studies should be conducted to better understand the true potential, mechanisms and patterns of taxanes induced pulmonary toxicity. [Table: see text]