Objective: Comparative assessment of the mortality rates of two septic patients' ages and/or gender subgroups, admitted to the intensive care unit of a university hospital. Methods: From December 2005 to April 2008, from a total of 628 patients, 133 were admitted to the intensive care unit with sepsis and included into two age subgroups: (G1) 14-40 years old and (G2) more than 50 years old. Patients aged between 41 and 50 years old (n = 8) were excluded. Demographic data, prognostic indicators (APACHE II score, organ dysfunction and circulatory shock) and outcome (mortality) were analyzed. Results: Of the G1 patients (n = 44), 27 were female (61.4%), and in G2 (n =

683 Background: Anti-EGFR plus chemotherapy (CT) promotes high response rates (RR) and median overall survival (OS) surpasses 30 months in RASwt/BRAFwt mCRC. After disease progression (PD), resistance mechanisms have been described. The aim of our study was to evaluate efficacy of anti-EGFR re-challenge (TRECC). Methods: We retrospectively analyzed a cohort of patients (pts) with mCRC. All pts had received anti-EGFR plus CT and were discontinued for different reasons. During the treatment, there was re-challenge with an anti-EGFR + CT. We aimed to evaluate progression-free survival (PFS) and OS after re-challenge and prognostic factors associated with PFS. Results: Sixty eight pts met the study criteria. Median follow-up after re-challenge was 39.3m. Discontinuation after first exposure was 25% due to PD; 75% for other reasons. Median anti-EGFR free interval was 10.5m. At re-challenge, main CT regime was: FOLFIRI 58.8%, Cetuximab and Panitumumab were used in 59 and 9 pts respectively. mPFS after re-challenge was 6.6m; mOS was 24.4m. Objective response rate (CR + PR) at re-challenge was 42.6%. In an univariate analysis, adverse prognostic factors related to PFS were: absence of objective response at 1st EGFR exposure (HR 2.12, CI:1.20-3.74 p = 0.009); PD as reason for 1st discontinuation (HR 3.44, CI:1.88-6.29 p < 0.0001); re-challenge at fourth or later lines (HR 2,51, CI:1.49-4.23 p = 0.001); panitumumab use (HR 2.26 CI:1.18-5.54 p = 0.017). In a multivariate model, only PD as reason for 1st discontinuation remained statistically significant (HR = 2.63, CI:1.14-6.03 p = 0.022). mPFS was 3.3m and 8.4m and mOS was 7,5m and 33,4m in patients with PD as reason for 1st discontinuation and other reasons respectively. Conclusions: Re-challenge therapy is commonly used due to paucity of effective lines of treament for mCRC. In our analysis, pts that stopped 1st anti-EGFR therapy due to PD have shorter survival, suggesting these pts do not benefit from TRECC. However, interruption due to treatment holiday after PR/CR resulted in longer PFS. In conclusion, for a selected group of pts, TRECC could be considered a strategy of treatment. Due to the limited number of pts, our data should be evaluated in a prospective cohort of patients.

524 Background: Follow-up surveillance is performed after primary treatment in colorectal cancer (CRC), but it is controversial in the literature the real benefit of an intensive examination in terms of outcomes and resources. Intensive follow-up after surgery for colorectal cancer has been challenged by some new published data (CEA watch trial and FACS trial). These new data suggest that a less intensive follow-up program based on carcinoembryonic antigen (CEA) measurements or CEA-Triggered imaging would be enough to detected most of the recurrences. We believe that there is a high percentage of patients with recurrence disease and normal CEA value, for whom image screening would be necessary to detect early disease recurrence suitable to metastasectomy with curative intention. Methods: This is a retrospective study that included 372 patients from a tertiary cancer center in São-Paulo (Brazil) diagnosed with colorectal adenocarcinoma stages I to III. We observed, after primary treatment, a pattern of recurrence detected either by CT (computed tomography) imaging only or CEA elevation and CT image in combination. Results: Out of the 372 patients analyzed, 110 (29,5%) had recurrent disease with a median follow-up time of 34 months. Of the 110 recurrences detected, 75 (68,18%) were detected by CEA elevation in combination with CT image, 33 (30%) were detected only by CT image and 2 (1,81%) neither by CT nor by CEA alteration. There was no clinic feature that would predict pattern of recurrence when analyzed by qui square test. Metastasectomy rate from this analysis 53,6% and it was similar among both groups. Recurrence rate after metastasectomy was 59,3%. There is a 5-year overall survival difference between patients that underwent or not metastasectomy (79,4% vs. 54%, p 0,01). Conclusions: CEA-based follow-up program and CEA-triggered imaging failed to detect early recurrence in almost 30% of cases. We believe that this number is high enough to allow us to continue to perform image test during CRC follow-up.

855 Background: The rate of primary resistance to modern first line (FL) chemotherapy regimen in the treatment of metastatic colorectal cancer (mCRC) is low. Progression Disease (PD) to FOLFOX in the FL is less than 15% in most trials. Prognostic factors associated with worse outcome in mCRC have been identified. However, primary resistance to Oxaliplatin (PROX) containing regimen is not well understood, as well as the role of salvage therapy in further lines of treatment. The aim of the study was to analyze clinical and pathological characteristics of patients with PROX. Methods: A retrospective, single center study included patients that presented PD in the first response evaluation with an Oxaliplatin containing regimen in the FL treatment of mCRC. We also evaluated the Overall Survival (OS) and progression free survival (PFS) of these patients to second and third line. Clinical and pathological variables were analyzed and correlated with (OS). Results: A total of 55 patients were inclued. Median age these cohort was 57 years. Female/Male rate was 42%/58%. Mucinous component was 27%. Right and Left colon was 27% and 66%, respectively. BRAF mutation (2/16 pts). Wild type KRAS was 44%. Synchronic metastasis was 75%. Ressection of metastasis was performed in 20%. Liver limeted disease was found in 45%. Main chemotherapy regimen containing oxaliplatin was FOLFOX (78%) in first line. Bevacizumab, Cetuximab and Panitumumab were used in 21.8%, 9%, 1.8%, respectively. OS was 9.4 months. PFS in second line 3.8 months (47 pts) and third line 3.5 months (18 pts). The only variable associated with longer survival was resection of metastasis (25.6 x 8.6 months, p=0.039). Conclusions: No clinical and pathological variable were able to predict primary resistance to Oxaliplatin containing regimen. However, we found a higher proportion of mucinous subtype. Patients submitted to resection of metastasis had almost three fold the survival of patient that did not underwent surgery. Refractory patients have a very short survival. Further lines of treatment are not able to rescue these patients. Further studies focusing in patients with primary resistance to chemotherapy in first line are needed.

Background: Premenopausal, high-risk, hormone receptor-positive breast cancer patients areoften treated with ovarian suppression in combination with aromatase inhibitors (AI). Thiscombination results in important adverse effects, particularly in sexual function, such as vaginaldryness and loss of libido. Vaginal estrogen is effective but may elevate serum estradiol levelsand, theoretically, may increase recurrence risk. Vaginal testosterone is also commonlyprescribed to ameliorate symptoms, though its safety remains uncertain, with limited availabledata. In our study, we aimed to determine the safety and efficacy, particularly regarding sexualfunction, of a low-dose, topical testosterone gel administration.Methods: This is a pilot, single-center study, designed to evaluate the efficacy of topicaltestosterone gel (3 mg/ml/per day) in improving sexual function in 30 premenopausal patientson ovarian suppression in combination with an AI. The primary safety endpoint was todetermine serum estradiol, measured by liquid chromatography mass spectrometry (E2) on amonthly a basis for 3 consecutive months. The primary efficacy endpoint was assessed by meansof the Female Sexual Function Index (FSFI) questionnaire, that include various domains of sexualfunction such as libido, sexual satisfaction and vaginal lubrication. The score can range from 2to 36, being 2 the lowest and 36 the highest sexual satisfaction. Patients had to have a baselineE2 of less than 2.7 pg/ml prior to study entry.Results: Herein, we report the preliminary results on the first 20 patients. The mean age was39.3 years, 85% had early or locally advanced disease and 15% had metastatic disease. Tenpatients completed the 3-month treatment, while five are still on therapy. Four of the 20discontinued treatment, mainly due to logistical difficulties during the follow-up visits. Onepatient had a localized allergic reaction and, also, discontinued treatment. A total of 15 patientsmaintained the value of E2 of less than 2,7 pg/ml during the 3-month treatment in all 3measurements. We observed an improvement in FSFI measures over the visits, with an increasefrom a mean of 10.2 at baseline to 19.4 at the third month (P&lt;0.001), with the greatestimprovement observed between the second and third months.Conclusion: Our preliminary findings suggest that topical testosterone appears safe andeffective in improving sexual function in patients on ovarian suppression and aromataseinhibitor. Further studies are clearly warranted. Citation Format: Patrícia Taranto, Diogo de Brito Sales, Luciano de Melo Pompei, Alessandro Leal, Gustavo Schvartsman, Antonio Carlos Buzaid. Safety and efficacy of low dose topical testosterone for sexual function improvement in women with breast cancer under treatment with ovarian suppression and aromatase inhibitor [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P4-10-05.