Prospective Radiologic-Pathologic Correlation of Macroscopic Volume and Microscopic Extension of Nonsolid Lung Nodules on Thin-section CT Images for Sublobar Resection and Stereotactic Radiotherapy Planning

INTRODUCTION

The objective of this study was to determine whether computed tomography (CT) could be a useful tool for nonsolid lung nodule (NSN) treatment planning, surgery or stereotactic body radiation therapy (SBRT), by assessing the macroscopic and microscopic extension of these nodules.

METHODS

The study prospectively included 23 patients undergoing anatomic resection at the Foch Hospital in 2020/2021 for NSN with a ground-glass component of more than 50%. Firstly, for each patient, both the macroscopic dimensions of the NSN were assessed on CT and during pathologic analysis. Secondly, the microscopic extension was assessed during pathologic examination. Wilcoxon sign rank tests were used to compare these dimensions. Spearman correlation test and Bland-Altman analysis were used to evaluate the agreement between radiological and pathologic measurements.

RESULTS

On CT, the median largest diameter and volume of NSN were 21 mm and 3780 cc, while on pathologic analysis, they were 15 mm and 1800 cc, respectively. Therefore, the largest diameter and volume of the NSN were significantly higher on CT than on pathological analysis. For microscopic extension, the median largest diameter and volume of NSN were 17 mm and 2040 cc, respectively. No significant difference was observed between the macroscopic size and the microscopic extension assessed during pathologic analysis. Moreover, correlation analysis and Bland-Altman plots showed that radiological and pathologic measurements could provide equivalent precision.

CONCLUSION

Our study showed that CT did not underestimate the macroscopic size and microscopic extension of NSN and confirmed that CT can be used for NSN treatment planning.

Efficacy and Safety of Combined Brain Stereotactic Radiotherapy and Immune Checkpoint Inhibitors in Non-Small-Cell Lung Cancer with Brain Metastases

Background: To analyze the outcomes of patients with brain metastases (BM) from non-small cell lung cancer (NSCLC) treated with immunotherapy (IT) and stereotactic radiotherapy (SRT) and to study the impact of the sequence between the two modalities. Methods: The authors reviewed the records of 51 patients with 84 BM from NSCLC treated at Institut Curie with IT and SRT. BM were categorized into three groups: ‘SRT before IT’, ‘concurrent SRT and IT’, and ‘SRT after IT.’ Regional progression-free interval (R-PFI) and overall survival (OS) were estimated using the Kaplan–Meier method. Results: After a median follow-up from SRT of 22.5 months (2.7–47.3), the 1-year and 2-year OS were 69.7% (95%CI [58.0–83.8]) and 44.0% [30.6–63.2], respectively. Concerning distant intracranial control, the 1-year and 2-year R-PFI were 40.1% [30.1–53.3] and 35.2% [25.1–49.4], respectively. Moreover, one-year R-PFI in ‘SRT before IT’, ‘concurrent SRT and IT’, and ‘SRT after IT’ groups were 24.1%, 49.6%, and 34.2%, respectively (p = 0.094). The type of therapeutic sequence did not appear to impact the risk of brain necrosis. Conclusions: The concurrent administration of SRT and IT appeared to offer the best locoregional control, without increasing the risk of toxicity, compared to patients treated with SRT before or after IT.

Efficacy of Large Use of Combined Hypofractionated Radiotherapy in a Cohort of Anti-PD-1 Monotherapy-Treated Melanoma Patients

To assess the role of radiotherapy in anti-PD-1-treated melanoma patients, we studied retrospectively a cohort of 206 consecutive anti-PD-1 monotherapy-treated advanced melanoma patients (59% M1c/d, 50% ≥ 3 metastasis sites, 33% ECOG PS ≥ 1, 33% > 1st line, 32% elevated serum LDH) having widely (49%) received concurrent radiotherapy, with RECIST 1.1 evaluation of radiated and non-radiated lesions. Overall (OS) and progression-free (PFS) survivals were calculated using Kaplan−Meier. Radiotherapy was performed early (39 patients) or after 3 months (61 patients with confirmed anti-PD-1 failure). The first radiotherapy was hypofractionated extracranial radiotherapy to 1−2 targets (26 Gy-4 weekly sessions, 68 patients), intracranial radiosurgery (25 patients), or palliative. Globally, 67 (32.5% [95% CI: 26.1−38.9]) patients achieved complete response (CR), with 25 CR patients having been radiated. In patients failing anti-PD-1, PFS and OS from anti-PD-1 initiation were 16.8 [13.4−26.6] and 37.0 months [24.6−NA], respectively, in radiated patients, and 2.2 [1.5−2.6] and 4.3 months [2.6−7.1], respectively, in non-radiated patients (p < 0.001). Abscopal response was observed in 31.5% of evaluable patients who radiated late. No factors associated with response in radiated patients were found. No unusual adverse event was seen. High-dose radiotherapy may enhance CR rate above the 6−25% reported in anti-PD-1 monotherapy or ipilimumab + nivolumab combo studies in melanoma patients.

Perspective: Do Fasting, Caloric Restriction, and Diets Increase Sensitivity to Radiotherapy? A Literature Review

Caloric starvation, as well as various diets, has been proposed to increase the oxidative DNA damage induced by radiotherapy (RT). However, some diets could have dual effects, sometimes promoting cancer growth, whereas proposing caloric restriction may appear counterproductive during RT considering that the maintenance of weight is a major factor for the success of this therapy. A systematic review was performed via a PubMed search on RT and fasting, or caloric restriction, ketogenic diet (>75% of fat-derived energy intake), protein starvation, amino acid restriction, as well as the Warburg effect. Twenty-six eligible original articles (17 preclinical studies and 9 clinical noncontrolled studies on low-carbohydrate, high-fat diets popularized as ketogenic diets, representing a total of 77 patients) were included. Preclinical experiments suggest that a short period of fasting prior to radiation, and/or transient caloric restriction during treatment course, can increase tumor responsiveness. These regimens promote accumulation of oxidative lesions and insufficient repair, subsequently leading to cancer cell death. Due to their more flexible metabolism, healthy cells should be less sensitive, shifting their metabolism to support survival and repair. Interestingly, these regimens might stimulate an acute anticancer immune response, and may be of particular interest in tumors with high glucose uptake on positron emission tomography scan, a phenotype associated with poor survival and resistance to RT. Preclinical studies with ketogenic diets yielded more conflicting results, perhaps because cancer cells can sometimes metabolize fatty acids and/or ketone bodies. Randomized trials are awaited to specify the role of each strategy according to the clinical setting, although more stringent definitions of proposed diet, nutritional status, and consensual criteria for tumor response assessment are needed. In conclusion, dietary interventions during RT could be a simple and medically economical and inexpensive method that may deserve to be tested to improve efficiency of radiation.

Tolerance of concurrent CDK inhibitor and radiation therapy in metastatic breast cancer patients

e12598

Background: Palbociclib, a small-molecule inhibitor of cyclin-dependent kinases (CDK4 and CDK6), combined with letrozole increases progression-free survival among patients with previously untreated ER-positive, HER2 negative advanced breast cancer. The purpose of our study was to retrospectively evaluate the tolerance of the concomitant association of Palbociclib and radiation therapy (RT) at Curie Institute. Methods: Between April 2017 and August 2019, 30 women with ER-positive, HER2 negative metastatic breast cancer received locoregional (LR) and/or symptomatic irradiation at a metastatic site concurrently with Palbociclib at a daily dose of 125 mg, from d1 to d21 every 28 days. Palbociclib was always associated with endocrine therapy: letrozole (with or without an LHRH analogue) or fulvestrant. Thirty-five sites were irradiated: nine patients received post-operative locoregional RT, including the chest wall or breast and lymph node areas, and 26 sites of metastases were irradiated: 17 at the spine, 7 peripheral skeletal lesions, 1 brain lesion and 1 choroidal lesion. The dose prescribed for locoregional mammary radiotherapy was 50 Gy in 25 fractions and varied for the treatment of metastatic sites: 20 Gy in 5 fractions (n = 13), 30 Gy in 10 fractions (n = 10) and 8 Gy in 1 fraction (n = 2). The brain metastasis was stereotactically treated (1 fraction of 18 Gy). The primary endpoint was toxicity scored according to the common terminology criteria for NCI adverse events, version v5.0. Results: Mean number of days of Palbociclib during RT was 8.8 days (range, 1 to 24 days). The most common acute toxicities were dermatitis (12/35, including 2 grade 2) and neutropenia (12/35, including 9 grade 2). Palbociclib had to be stopped during the RT of two patients (2/30): one patient treated locoregionally (bilateral breast and lymph nodes irradiation) developed a grade 3 dermatitis and febrile neutropenia, another treated locoregionally developed grade 2 dysphagia. After a median follow-up since the end of RT of 17 months (6 – 31 months, SD 8), none of the patients have so far exhibited late toxicity. Conclusions: Concomitant administration of palbociclib with RT was reasonably well tolerated in our series of 30 patients. Given this experience, palbociclib should not be discontinued during radiation therapy. Nevertheless, our findings should be confirmed in prospective registration studies collecting larger number of patients.

Radiotherapy mucositis in head and neck cancer: prevention by low-energy surface laser

BACKGROUND

Modern radiotherapy (RT) planning techniques and the use of oral supportive care have reduced the occurrence of acute radiation-induced toxicities. Oral mucositis remains a major concern in patients with head and neck cancer as it can compromise treatment compliance and outcome.

OBJECTIVE

To report the rate of mucositis with the preventive use of surface low-level laser therapy in patients with head and neck cancer.

METHODS

Forty patients treated with definitive (n=27) or adjuvant (n=13) RT using volumetric arc therapy between August 2014 and October 2015 for squamous cell carcinoma of the head and neck were included. All patients were treated using photobiomodulation using surface low-level laser therapy (Heltschl kind FL 3500, 350 mW), 3 times a week during the whole treatment course. The grade of mucositis was obtained from week 1 to week 7 and at 1 month.

RESULTS

The median RT dose was 70 Gy (64-70). Concomitant chemotherapy was administered in 29 patients. According to the Common Terminology Criteria for Adverse Events (CTCAE) v. 3, grade 0, 1, 2 and 3 mucositis was observed in 9 (22.5%), 9 (22.5%), 16 (40%) and 6 (15%) patients at week 7, and 32 (80%), 2 (5%), 3 (7.5%) and 3 (7.5%) patients at 1 month following treatment. No grade 4 occurred. Median average and maximum dose to the oral mucosa was 42 Gy (12.9-66.3) and 66.6 Gy (39-76), respectively.

CONCLUSION

Despite a substantial dose to the oral mucosa, the rate of acute radiation-induced mucositis of grade ≥3 remains low in patients receiving extraoral low-energy laser during RT.

Gastric fluid pH and volume in gynaecologic out-patients. Influences of cimetidine and cimetidine-sodium citrate combination

Eighty consecutive ASA physical status 1 women scheduled for day-case gynaecological laparoscopy under general anaesthesia were randomly allocated during the pre-operative visit to receive one of four premedication regimes. Patients in group 1 received hydroxyzine 100 mg; patients in group 2 received hydroxyzine 100 mg and cimetidine 400 mg; patients in group 3 received hydroxyzine 100 mg and effervescent cimetidine (cimetidine 200 mg + sodium citrate 1.8 g). All were given orally in 30 ml of water, 90 min before anaesthetic induction. Patients in group 4 received effervescent cimetidine orally in 30 ml of water 5 min before anaesthetic induction. Following induction of anaesthesia, gastric pH and residual volume (phenol red dilution technique) were measured. Gastric pH was higher (P < 0.05) in groups 2, 3 and 4 (medians: 5.71, 4.84, 6.07, respectively) than in group 1 (2.18). No patient had a gastric pH < or = 2.5 in group 4 compared with 13/14 n group 1, 1/15 in group 2 and 2/14 in group 3 (P < 0.0001). Mean gastric volumes were higher (P < 0.05) in group 4 (30.4 +/- 23.2 ml) than in groups 1, 2 and 3 (11.8 +/- 6.4, 15.8 +/- 11.2, 17.2. +/- 24.4 ml, respectively). Nine of the 19 patients in group 4 had a volume higher than 25 ml. Only one patient in group 1 had both gastric pH < or = 2.5 and volume > or = 25 ml. The administration of effervescent cimetidine 5 min prior to anaesthetic induction seems to be an easy and effective method of decreasing the acidity of gastric contents in day surgery.