GAGE mediates radio resistance in cervical cancers via the regulation of chromatin accessibility.

Radiotherapy (RT) resistance is a major cause of treatment failure in cancers that use definitive RT as their primary treatment modality. This study identifies the cancer/testis (CT) antigen G antigen (GAGE) as a mediator of radio resistance in cervical cancers. Elevated GAGE expression positively associates with de novo RT resistance in clinical samples. GAGE, specifically the GAGE12 protein variant, confers RT resistance through synemin-dependent chromatin localization, promoting the association of histone deacetylase 1/2 (HDAC1/2) to its inhibitor actin. This cumulates to elevated histone 3 lysine 56 acetylation (H3K56Ac) levels, increased chromatin accessibility, and improved DNA repair efficiency. Molecular or pharmacological disruption of the GAGE-associated complex restores radiosensitivity. Molecularly, this study demonstrates the role of GAGE in the regulation of chromatin dynamics. Clinically, this study puts forward the utility of GAGE as a pre-screening biomarker to identify poor responders at initial diagnosis and the therapeutic potential of agents that target GAGE and its associated complex in combination with radiotherapy to improve outcomes.

Phase 1 Study of Low-Dose Fractionated Whole Abdominal Radiation Therapy in Combination With Weekly Paclitaxel for Platinum-Resistant Ovarian Cancer (GCGS-01).

PURPOSE: Low-dose fractionated whole abdominal radiation therapy (LDFWART) has synergistic activity with paclitaxel in preclinical models. The aim of this phase 1 trial was to determine the recommended phase 2 dose and preliminary activity of weekly paclitaxel (wP) concurrent with LDFWART in patients with platinum-resistant ovarian cancer (PROC). METHODS AND MATERIALS: Patients were enrolled at de-escalating dose levels of wP (part A), starting at 80 mg/m2, concurrent with fixed-dose LDFWART delivered in 60 cGy fractions twice-daily, 2 days per week, for 6 continuous weeks. After completing the 6-week course of wP + LDFWART, patients received wP until disease progression. Dose-limiting toxicity was evaluated during the first 3 weeks of wP + LDFWART. At wP (80 mg/m2) + LDFWART, no dose-limiting toxicities were observed; this was the established maximum tolerated dose. The trial was expanded (part B) with 7 additional patients with platinum-resistant, high-grade serous ovarian cancer to confirm toxicity and activity. RESULTS: A total of 10 heavily pretreated patients were recruited (3 patients to part A, 7 patients to part B). They had received a median of 5 prior lines of therapy, and 70% of patients had received prior wP; 60% of patients completed 6 weeks of wP + LDFWART. Common related grade ≥3 adverse events were neutropenia (60%) and anemia (30%). Median progression-free survival was 3.2 months, and overall survival was 13.5 months. Of patients evaluable for response, 33% (3 of 9) achieved confirmed biochemical response (CA125 decrease >50% from baseline), 11% (1) achieved a partial response, and 5 patients had stable disease, giving a disease control rate of 66.7% (6 of 9). Four patients had durable disease control of ≥12 weeks, completing 12 to 21 weeks of wP. CONCLUSIONS: The recommended phase 2 dose of wP + LDFWART for 6 weeks is 80 mg/m2. Encouraging efficacy in heavily pretreated PROC patients was observed, suggesting that further development of this therapeutic strategy in PROC should be considered.

Navigating the challenges of the COVID-19 outbreak: Perspectives from the radiation oncology service in Singapore.

In December 2019, pneumonia of unknown cause was reported by China to WHO. The outbreak was found to be caused by a coronavirus which was officially named "severe acute respiratory syndrome coronavirus 2" (SARS-CoV-2), and the disease caused by it was named 'COVID-19'. The first case in Singapore was confirmed on 23rd January 2020. With lessons learnt from the SARS epidemic in 2003 and the H1N1 flu pandemic in 2009, Singapore was much better prepared to deal with the virus outbreak. The government has taken swift measures to contain and break the chain of transmission. Healthcare workers face the challenge of keeping patients and staff safe from the disease. There is a higher risk of mortality of COVID-19 in cancer patients and hence unique considerations for a radiation oncology department operating in an infectious disease outbreak. This article is the recommendations and adapted workflow from the two National Cancer Centres in Singapore with the endorsement by the working committee of the Chapter of Radiation Oncology, Academy of Medicine, Singapore. It highlights the challenges that radiation oncology departments in Singapore face and the appropriate recommended responses. This includes interventions, business continuity plans and workflow in managing a COVID-19 positive patient on radiotherapy.

Does external beam radiation boost to pelvic lymph nodes improve outcomes in patients with locally advanced cervical cancer?

BACKGROUND: Current recommendation for locally advanced cervical cancer includes pelvic external beam radiation therapy (EBRT) with concurrent chemotherapy followed by brachytherapy. Involvement of pelvic lymph nodes is an important prognostic factor in locally advanced cervical cancer and recurrence commonly occurs despite definitive treatment. To date, there is no standard guideline on whether an EBRT boost should be applied to involved pelvic lymph nodes. Our study aims to assess if pelvic EBRT boost would reduce recurrence, benefit survival, and affect associated toxicities. METHODS: We conducted a retrospective review of locally advanced cervical cancer cases treated with definitive treatment at our institution. Involvement of pelvic lymph nodes were assessed on CT, MRI (> 10 mm or suspicious features) or PET scan (SUVmax > 2.5). EBRT dose ranged from 45 to 50.4 Gy with nodal boost ranging from 3.6-19.8 Gy. RESULTS: Between 2008 to 2015, 139 patients with locally advanced cervical cancer underwent treatment. Sixty-seven patients had positive pelvic lymph nodes, of which 53.7% received a nodal boost. Five-year recurrence free survival was 48.6% with vs. 64.5% without nodal boost (P = 0.169) and 5-year overall survival in those with positive pelvic lymph nodes was 74.3% with vs. 80.6% without nodal boost (P = 0.143). There was no significant difference in toxicity with nodal boost. CONCLUSIONS: EBRT boost to pelvic lymph nodes does not reduce recurrence or improve survival in locally advanced cervical cancer with lymph node involvement at diagnosis.

Novel anesthetic technique for combined intracavitary and interstitial brachytherapy for cervix cancer in an outpatient setting.

PURPOSE: To determine the feasibility and safety of outpatient combined intracavitary and interstitial brachytherapy for cervix cancer with sedation and local anesthesia. MATERIAL AND METHODS: We included patients diagnosed with non-metastatic cervix cancer and have completed brachytherapy between December 2015 and December 2016. Moderate to deep sedation was achieved using intravenous midazolam, propofol, fentanyl, and oxycodone. Local anesthesia was achieved with 2% lignocaine gel and a paracervical block containing a mixture of 1% ropivacaine, 2% lignocaine, and 1 : 1,000 adrenaline. Ceftriaxone and ondansetron were given prophylactically. Physiologic monitoring was performed throughout and pain scores were recorded using the Numeric Rating Scale. Follow-up was conducted at 8 weeks from the last fraction of brachytherapy. The feasibility and safety endpoints were a post-anesthesia discharge score (PADS) of 9 or above, and no grade 3 or above adverse events, respectively. RESULTS: A total of thirty-five brachytherapy insertions were carried out on nine patients. The median age of the patients was 56 years (range, 40-65). Eight patients had American Society of Anesthesiologists' physical status of I or II, and one had a status of III. The mean duration of the insertion was 39 minutes (standard deviation [SD] = 14), during which no adverse events occurred. There was no significant nausea or vomiting post-sedation. The median pain scores post-insertion and during recovery were 0 (range, 0-6) and 0 (range, 0-7), respectively. At discharge, all patients had pain scores of 0 and maximum PADS of 10. The mean time to discharge was 4.1 hours (SD = 0.95). There were no brachytherapy-related admissions or complications. CONCLUSIONS: Outpatient combined intracavitary and interstitial brachytherapy for cervix cancer with sedation and local anesthesia is feasible and safe. This could potentially lead to significant cost savings.

Palliative radiotherapy for gastric cancer: a systematic review and meta-analysis.

BACKGROUND/PURPOSE: To review the efficacy and toxicity of palliative radiotherapy (RT) for symptomatic locally advanced gastric cancer (GC) and to determine the optimal RT schedule for symptom palliation. METHODS: We searched MEDLINE and CENTRAL for eligible studies published from 1995 to 2015. Outcomes of interest were relief of bleeding, pain and obstruction. RESULTS: Seven non-comparative observational studies were included. There were large variations in RT dose and fractionation. The pooled overall response rates for bleeding, pain and obstruction symptoms were 74%, 67% and 68% respectively. There was no difference in response rate of bleeding between regimens with high biological equivalent dose (BED) of ≥ 39Gy versus regimens with low BED<39Gy regimens (p value =0.39). Grade 3 to 4 toxicities occurred in up to 15% of patients for patients treated with RT alone and up to 25% of patients treated with chemoradiotherapy. Health-related quality of life (HRQL) outcomes were not reported. CONCLUSION: More than two-thirds of patients receiving RT would have a clinical benefit. Low BED regimens appear to be adequate for symptom palliation. Toxicity rates appear acceptable for patients treated with RT alone. The optimal dose fractionation regimen for symptom palliation remains unclear. Prospective studies to determine the effects of palliative gastric RT on HRQL outcomes are warranted.

Feasibility study of toxicity outcomes using GEC-ESTRO contouring guidelines on CT based instead of MRI-based planning in locally advanced cervical cancer patients.

PURPOSE: To report late rectal and bladder toxicity outcomes of a CT-based image-guided brachytherapy (IGBT) technique for treatment of cervical cancer. METHODS AND MATERIALS: Between 2008 and 2014, 95 women with International Federation of Gynecology and Obstetrics stage IB to IVA cervical carcinoma treated with definitive concurrent cisplatin-based chemotherapy and external beam radiation therapy 50.4 Gy in 28 fractions followed by planned prescription dose of 7 Gy × 4 fractions of high-dose-rate IGBT was retrospectively reviewed. At each implantation, all patients had a urinary catheter in situ and received bowel enema before undergoing planning CT simulation. A high-risk clinical target volume (HRCTV) as per GEC-ESTRO guidelines and the entire cervix, rectum, and bladder was contoured on the simulation CT according to Radiation Therapy Oncology Group Gynaecology Contouring Atlas. Reported doses to HRCTV and organs at risk were recorded. Toxicities were recorded using National Cancer Institute Common Terminology Criteria for Adverse Events version 3. RESULTS: The median followup time was 29 months. The mean HRCTV equivalent dose in 2 Gy fractions (EQD2) of external beam radiation therapy combined with brachytherapy was 80 Gy (standard deviation [SD], 11), and the rectal doses to 2 cm3 (D2cc) EQD2 and bladder D2cc EQD2 were 74 Gy (SD, 6) and 79 Gy (SD, 15), respectively. Twenty-two patients (23%) had grade 2 proctitis and 10 patients (11%) had grade 3 proctitis. Four patients (4%) had grade 2 cystitis and two patients (2%) had grade 3 cystitis. No patients had ≥ grade 4 toxicity. CONCLUSIONS: Despite CT-based brachytherapy planning, reported organ at risk toxicity was still significant compared with reported MRI-based planning series. Coimplementation of interstitial IGBT using the European Study on MRI-guided Brachytherapy in Locally Advanced Cervical Cancer (EMBRACE) protocol or using intensity-modulated radiation therapy during the external beam phase treatment might help to limit these late toxicities.

Long-term remission after low dose radiotherapy in patient with extensive squamous cell carcinoma of the hand: A case report.

RATIONALE FOR CASE REPORT: Cutaneous Squamous Cell Carcinoma (cSCC) of the hand is uncommon and tends to have poorer outcomes. Surgical resection with wide margins around the tumor is recommended as the treatment of choice, and radiotherapy is considered second-line treatment. Nodal evaluation involves dissection necessitating some morbidity. The role of less invasive modalities of nodal evaluation is not well established. CASE PRESENTATION: We report a case of locally advanced case of hand cSCC. Positron emission tomography-computed tomography (PET-CT) showed disease involving full thickness of the hand as well as the ipsilateral axillary node. To achieve adequate surgical margins would have necessitated amputation at the wrist, which the patient did not consent to. Instead, he was given a two-and-a-half week course radiotherapy to the hand without axillary radiation. With the radiotherapy treatment, he managed to achieve complete remission of disease while retaining full function of the hand, which was maintained at 22 months post-treatment. MAIN LESSONS: CSCC of the hand is uncommon and challenging to treat. Radiotherapy is a highly effective treatment modality which is able to achieve functional preservation. Care should be taken when evaluating nodal status using PET-CT.

Mastectomy rates remain high in Singapore and are not associated with poorer survival after adjusting for age.

Recent reports have suggested that women undergoing mastectomy, instead of wide local excision (WLE) for Stage I and II breast cancers have poorer overall survival. This is particularly important in our setting where mastectomy rates are high. In this study, we evaluated the trends in mastectomy and WLE over a 10-year period at a single institute, identified factors more common among women who underwent mastectomy and specifically examined the effect of surgery on outcome. Retrospective review was performed of 2244 women who underwent curative surgery for non-metastatic breast cancer at our institute from 1st January 2001 to 31st December 2010. Mastectomy rates remained high over the 10 years, ranging from 43 to 59 %. Older women, those with symptoms, larger tumours and clinical nodal involvement were more likely to receive mastectomy (P < 0.05). The type of surgery (mastectomy or WLE) did not affect survival in women with ductal carcinoma-in situ, while women with invasive cancer appeared to survive longer when treated with WLE (P < 0.01). Surgery type was not an independent predictor of overall survival and the survival advantage with WLE did not remain after adjusting for age, implying that the effect on survival had been confounded by the fact that older women tended to undergo mastectomy. Mastectomy remains common among our local women, with further studies being needed to evaluate factors involved in decision-making. Older women and those with significant co-morbidities were more likely to undergo mastectomy and this contributed to an apparent survival advantage following WLE.

Clinical outcome of palliative radiotherapy for locally advanced symptomatic gastric cancer in the modern era.

The purpose of this study was to report the outcomes of patients with symptomatic locally advanced/recurrent gastric cancer treated with radiotherapy (RT) using modern 3-dimensional conformal techniques.We retrospectively reviewed patients who had palliative RT for index symptoms of gastric bleeding, pain, and obstruction. Study endpoints included symptom response, median survival, and treatment toxicity.Of 115 patients with median age of 77 years, 78 (67.8%) patients had metastatic disease at the time of treatment. Index symptoms were gastric bleeding, pain, and obstruction in 89.6%, 9.2%, and 14.3% of patients, respectively. Dose fractionation regimen ranged from 8-Gy single fraction to 40 Gy in 16 fractions. One hundred eleven patients (93.3%) were computed tomography (CT) planned. Median follow-up was 85 days. Response rates for bleeding, pain, and obstruction were 80.6% (83/103), 45.5% (5/11), and 52.9% (9/17), respectively, and median duration of response was 99 days, 233 days, and 97 days, respectively. Median survival was 85 days. Actuarial 12-month survival was 15.3%. There was no difference in response rates between low (≤39 Gy) and high (>39 Gy) biologically effective dose (BED) regimens (α/ß ratio = 10). Median survival was significantly longer in patients who responded to RT compared with patients who did not (113.5 vs 47 days, P < 0.001). Three patients (2.6%) had grade 3 Common Toxicity Criteria equivalent toxicity (nausea/vomiting/anorexia).External beam RT delivered using 3-dimensional conformal techniques is highly effective and well tolerated in the local palliation of gastric cancer, with palliation lasting the majority of patient's lives. Short (≤39 Gy BED) RT schedules are adequate for effective symptom palliation. A phase II study of palliative gastric RT is ongoing.

Oncologic outcomes of neoadjuvant chemoradiation for locally advanced rectal cancer: a single-institution experience.

INTRODUCTION: This study reports the outcomes of patients with locally advanced rectal cancer treated with neoadjuvant chemoradiation followed by surgery in a local population of Singapore. MATERIALS AND METHODS: The records of 85 patients who underwent neoadjuvant chemoradiation for locally advanced rectal cancer followed by surgery at the Tan Tock Seng Hospital (TTSH) between November 2002 and January 2012 were reviewed. The treatment protocol comprised radiotherapy to a total dose of 50.4 Gy concurrent with 5-fluorouracil-based chemotherapy. Patients underwent total mesorectal excision surgery following the completion of neoadjuvant chemoradiation. Local control, disease-free survival and overall survival were analysed using Kaplan-Meier methods. RESULTS: Median age of the patients was 61 years. All of them completed radiotherapy. One patient did not complete neoadjuvant chemotherapy. The median time to surgery was 52 days. Fifty-five percent (47 of 85) of patients achieved pathological downstaging and 13% (11 of 85) of patients had a pathologic complete response to preoperative treatment. The neoadjuvant chemoradiation was well tolerated. Four percent of patients had grade 3 diarrhoea and 4% of them had grade 3 dermatitis. There were no grade 4 toxicities. With a median follow-up of 41 months, the 5-year actuarial local recurrence, disease-free survival and overall survival rates were 7%, 71.9%, and 83.2% respectively. Univariate analysis showed that patients with positive surgical margins had significantly worse disease-free survival and overall survival (P=0.012 and P<0.001 respectively) and a trend towards a higher rate of local recurrence (P=0.08). CONCLUSION: Our study provides evidence that neoadjuvant chemoradiation is an effective treatment for locally advanced rectal cancer. Our outcomes are comparable with internationally published data and demonstrate the reproducibility of the neoadjuvant approach in an Asian population.

Body mass index and patient CT measurements as a predictor of benefit of intensity-modulated radiotherapy to the supraclavicular fossa.

BACKGROUND: Irradiation of the supraclavicular fossa is commonly used as part of adjuvant breast radiotherapy. Intensity-modulated radiotherapy (IMRT) may be used to target this region accurately, and there are subgroups of patients that may benefit more from IMRT than others. We identify the benefit of IMRT over fixed-depth dose prescription to the supraclavicular fossa in patients of different builds in a clinical setting. METHODS: Fifteen patients who received radiotherapy to the left breast and supraclavicular fossa were selected. Computed tomographic planning was used to generate plans for supraclavicular fossa coverage. Dose prescription to 1.5 cm and 3.0 cm depths was compared with IMRT plans. Coverage of the planning target volume and dose to the organs at risk were compared and correlated with patient body mass index (BMI) and computed tomography measurements. RESULTS: Within the IMRT group, increasing depth of the supraclavicular fossa produced significantly better coverage of the planning target volume with IMRT. IMRT resulted in lower mean doses to the brachial plexus (P = 0.00) when compared with 1.5 cm and 3 cm depth dose prescriptions, but higher maximum brachial plexus doses. IMRT was more beneficial in patients with lower BMI because this resulted in a decreased maximum brachial plexus dose (P-values of 0.03 and 0.001 when compared with 1.5 cm and 3.0 cm depth dose prescriptions, respectively). Higher patient BMI resulted in a lower dose contribution of IMRT to the cord (P-values 0.066 and 0.034 when compared with 1.5 cm and 3.0 cm depth dose prescriptions respectively). CONCLUSION: IMRT of the supraclavicular fossa results in lower brachial plexus doses for patients with low BMI while patients with higher BMI benefit from lower mean cord doses. IMRT provides superior coverage of the planning target volume, especially in patients with a deeper supraclavicular fossa.

Outcome of 6 fractions of 5.3 Gray HDR brachytherapy in combination with external beam radiotherapy for treatment of cervical cancer.

OBJECTIVE: To review the characteristics, outcomes and toxicities of cervical cancer patients treated with 6 fractions of brachytherapy after external beam radiotherapy (EBRT). METHODS: All patients diagnosed with cervical cancer from 2000 to 2009 who were referred for radical treatment and who received 6 fractions of brachytherapy were retrospectively reviewed. Overall survival (OS), disease free survival (DFS), local control (LC), distant control (DC) rate, acute and late toxicities were the primary endpoints. RESULTS: Thirty-two patients with mainly advanced stage squamous cell carcinoma were identified and reviewed. Patients received EBRT of 45 to 50.4 Gy in 1.8 Gy daily fractions followed by 6 sessions of 3 channel brachytherapy of 5.3 Gy prescribed to point H. Response rates to treatment were good, with no residual disease in 84% six weeks after the completion of treatment. With a median follow up time of 8.1 years, the five-year OS, DFS, LC and distant control rates were 75%, 68.5%, 92.8% and 76.9% respectively. None of the patients developed any G3-4 acute toxicity but one patient who had advanced disease developed G3-4 proctitis with a fistula formation. CONCLUSIONS: HDR brachytherapy utilizing 6 fractions of 5.3 Gy prescribed to point H with concurrent chemo-radiation is superior in terms of OS and LC to regimens that deliver a lower EQD2 dose to point A/H and is associated with very low rates of toxicities.

Outcomes following treatment for patients with cranial nerve involvement from nasopharyngeal cancer.

INTRODUCTION: Patients with locally advanced nasopharyngeal carcinoma (NPC) commonly present with cranial nerve (CN) involvement, which can cause significant morbidity. We aimed to characterise the pattern of involvement and outcomes of these patients, as well as determine if these differed according to the mode of diagnosis. METHODS: Patients were included if they had non-distant metastatic NPC, presented with CN involvement and completed radiotherapy treatment between 2002 and 2008. The clinical response was categorised as complete response, partial response, stable or progressive disease. The radiological response was assessed using the Response Evaluation Criteria in Solid Tumors criteria. The loco-regional control and disease-free survival rates were estimated with the Kaplan-Meier method. RESULTS: Forty-seven patients fulfilled the inclusion criteria. CN lesions were diagnosed on clinical examination in 15% of patients, radiologically in 40% and both clinically and radiologically in 45% of patients. A complete or partial response of the CN lesions was seen clinically in 82% and radiologically in 95% of patients. The 3-year local relapse free survival was 64.3%, distant metastasis-free survival was 46.1% and overall survival was 82.8%. There were no differences in outcomes between patients with clinically versus radiologically detected CN lesions. CONCLUSION: Most of these patients are likely to undergo clinical and/or radiological resolution of the nerve lesions following chemoradiotherapy, but the outcome was not determined by the mode of diagnosis (radiological or clinical).

2D to 3D Evaluation of Organs at Risk Doses in Intracavitary Brachytherapy for Cervical Cancer.

PURPOSE: To compare International Commission on Radiation Units and Measurements (ICRU) bladder and rectum reference points doses with volumetric doses in 3D intracavitary brachytherapy (ICBT) for cervical cancer. Also to compare bladder, rectum and sigmoid (organs at risk, OARs) volume doses with dose constraints recommended by the (GYN) GEC-ESTRO Working Group. MATERIAL AND METHODS: A retrospective study was carried out on 10 patients with a total of 55 fractions CT-based high dose rate (HDR) ICBT. ICRU bladder (bICRU) and rectum (rICRU) points were defined according to ICRU Report 38 on the CT images and prospectively kept to less than 80% of prescription dose to Point A during real treatment planning. Post-treatment, outer wall of OARs were contoured and minimum dose to 2cc (D2cc) of the most irradiated part of the OARs was obtained from the dose-volume histogram (DVH). Total dose (external beam radiotherapy plus ICBT) were computed with ICRU point dose and D2cc and compared. RESULTS: The mean ICRU point dose and D2cc volume dose were found to be significantly different for bladder (per fraction: p = 0.000; total dose: p = 0.004) but no differences were found for rectum (per fraction: p = 0.055; total dose: p = 0.090). bICRU point dose underestimated D2cc dose with an average ratio of 1.34 ± 0.34. 3 out of 10 patients, 7 out of 10 patients, and 5 out of 10 patients exceeded the recommended dose constraint for bladder, rectum, and sigmoid, respectively. CONCLUSIONS: bICRU was not representative of bladder D2cc and resulted in different total dose. rICRU was found to be similar to D2cc dose and was reliable in total dose computation. Our current institutional practice of point-based planning in ICBT resulted in significant number of patients' OARs doses exceeded the volume constraint, because the total dose concept was not used propectively in planning.