Phase II Study of a Radiotherapy Total Dose Increase in Hypoxic Lesions Identified by 18F-Misonidazole PET/CT in Patients with Non-Small Cell Lung Carcinoma (RTEP5 Study)

See an invited perspective on this article on page 1043.This multicenter phase II study investigated a selective radiotherapy dose increase to tumor areas with significant ¹⁸F-misonidazole (¹⁸F-FMISO) uptake in patients with non-small cell lung carcinoma (NSCLC). Methods: Eligible patients had locally advanced NSCLC and no contraindication to concomitant chemoradiotherapy. The ¹⁸F-FMISO uptake on PET/CT was assessed by trained experts. If there was no uptake, 66 Gy were delivered. In ¹⁸F-FMISO-positive patients, the contours of the hypoxic area were transferred to the radiation oncologist. It was necessary for the radiotherapy dose to be as high as possible while fulfilling dose-limiting constraints for the spinal cord and lungs. The primary endpoint was tumor response (complete response plus partial response) at 3 mo. The secondary endpoints were toxicity, disease-free survival (DFS), and overall survival at 1 y. The target sample size was set to demonstrate a response rate of 40% or more (bilateral α = 0.05, power 1-β = 0.95). Results: Seventy-nine patients were preincluded, 54 were included, and 34 were ¹⁸F-FMISO-positive, 24 of whom received escalated doses of up to 86 Gy. The response rate at 3 mo was 31 of 54 (57%; 95% confidence interval [CI], 43%-71%) using RECIST 1.1 (17/34 responders in the ¹⁸F-FMISO-positive group). DFS and overall survival at 1 y were 0.86 (95% CI, 0.77-0.96) and 0.63 (95% CI, 0.49-0.74), respectively. DFS was longer in the ¹⁸F-FMISO-negative patients (P = 0.004). The radiotherapy dose was not associated with DFS when adjusting for the ¹⁸F-FMISO status. One toxic death (66 Gy) and 1 case of grade 4 pneumonitis (>66 Gy) were reported. Conclusion: Our approach results in a response rate of 40% or more, with acceptable toxicity. ¹⁸F-FMISO uptake in NSCLC patients is strongly associated with poor prognosis features that could not be reversed by radiotherapy doses up to 86 Gy.

Evaluation of toxicity and efficacy of 186Re-hydroxyethylidene diphosphonate in patients with painful bone metastases of prostate or breast cancer

Twenty-eight patients (12 men with prostate cancer, 16 women with breast cancer) were included in a phase II trial to evaluate the efficacy of 186Re-hydroxyethylidene diphosphonate (HEDP) on pain from bone metastasis and the toxicity of this agent.

METHODS

After intravenous administration of 1295 MBq 186Re-HEDP, the efficacy was evaluated by means of a daily log.

RESULTS

We observed an objective response in 67% of prostate cancer patients and in 36% of breast cancer patients. The mean duration of response was 45 d for prostate cancer patients and 24 d for breast cancer patients. No major adverse effects were observed. Marrow toxicity did not exceed grade 2 for white blood cells and grade 3 for platelets using National Cancer Institute criteria.

CONCLUSION

186Re-HEDP provides safe symptomatic relief of pain in prostate cancer patients. The benefit of this treatment is less clear in breast cancer patients. Further studies should be conducted to evaluate treatment by 186Re-HEDP at an earlier stage of the disease.

Unusual case of diagnosis of pigeon breeder's hypersensitivity pneumonitis with ventilation-perfusion lung scan

The authors describe a patient thought to have pulmonary embolism. Results of a perfusion scan were normal, but Tc-99m DTPA aerosol ventilation lung scan showed, in successive views, decreased activity of the deposited aerosol. The lung Tc-99m DTPA clearance was measured and was markedly increased. This suggested possible hypersensitivity pneumonitis, which was later confirmed as pigeon breeder's disease. The decreased activity observed on the DTPA ventilation scan must be directed toward increased lung clearance and its measurement.

Experimental radiation pneumonitis studied with indium-111-pentetreotide

OBJECTIVES

To understand the evolution of lung uptake of 111-In-Pentetreotide in a rat model of pulmonary radiation pneumonitis.

METHODS

A 15 Gy 60-Co thoracic irradiation (1.4 Gy/min) was delivered to Wistar rats. Irradiated and control animals were studied during 8 weeks after irradiation. 24 hours after an injection of 111-In-pentetreotide (12-18 MBq), the uptake in the lung tissue (ULT), in the alveolar cells (UpC) and in different organs, was determined. Histological examinations were performed.

RESULTS

ULT and UpC after irradiation increased significantly peaking at 4 weeks (ULT: 32.8 +/- 13.0 in 10(-5) of the injected dose versus 10.8 +/- 2.0 for control; and, UpC was 19.3 +/- 7.2 versus 7.3 +/- 4.1) and decreased afterwards. Pre-injection of cold octreotide decreased the lung uptake. This evolution parallels the histological changes: alveolitis with granulomas in the interstitium at 4 weeks followed by development of sites of interstitial fibrosis. These observations suggest that the uptake is due to activated cells, mainly macrophages within the granulomas and in the alveoli, expressing somatostatin receptors.

CONCLUSION

1) The uptake of 111-In-pentetreotide in injured lungs after irradiation, already described in man, was confirmed in a rat model; 2) our results suggest that it is possible to follow the evolution of radiation lung injury by using In-111-pentetreotide.

Factor analysis of dynamic series (FADS) in somatostatin receptor imaging

The aim of this article was to study the physiopathology of tumoral uptake of 111In-pentetreotide using factorial analysis of dynamic series (FADS) and to assess the usefulness of this analysis in somatostatin receptor scintigraphy.

METHODS

Forty-one patients were included, 24 women and 17 men. After intravenous injection of 111 MBq 111In-pentetreotide, dynamic image acquisition (68 images of 30 s) began in front of the suspected tumoral site: thoracic in 10 patients with medullary carcinoma of the thyroid and 2 patients with bronchogenic carcinoid, and abdominal in 12 cases of midgut carcinoid and 17 cases of other gastroenteropancreatic neuroendocrine tumors. FADS was performed with FAMIS software. Static images were obtained 4 h and 24 h later. For every patient, surgery and/or clinical follow-up (4 y) was used to classify results as true (T) or false (F) positive (P) or negative (N) and to evaluate both the sensitivity of static images and the usefulness of FADS.

RESULTS

Of the 14 cases of carcinoid tumor, 5 patients were TN; 9 patients were TP with static images but only 8 were TP with FADS (a bronchogenic carcinoid of 6 mm was missed). Of the 17 cases of gastroenteropancreatic neuroendocrine tumor, static images were TP in 9 patients, and FADS were TP in 5 of these patients (and 4 FN). Static images and FADS were FN in 4 patients and TN in 3 patients, and in the 2 last patients static images were FP, but FADS were TN. Of the 10 cases of medullary carcinoma of the thyroid, static images and FADS were TN in 1 patient, static images were TP in 3 patients and FADS were TP in 2 of these patients (and 1 FN). In the six last cases, static images were FN, but FADS were FN in 3 patients and TP in 3 patients, showing an infiltrate.

CONCLUSION

FADS demonstrates that tumoral kinetics are similar to those of the spleen. FADS can show a diffuse tumoral uptake corresponding to tumoral infiltrate in medullary carcinoma of the thyroid or in hepatic miliaria, whereas static images were normal or doubtful.