Immune checkpoint inhibitor treatment of a first cancer is associated with a decreased incidence of second primary cancer.

BACKGROUND: Second primary cancers (SPCs) are diagnosed in over 5% of patients after a first primary cancer (FPC). We explore here the impact of immune checkpoint inhibitors (ICIs) given for an FPC on the risk of SPC in different age groups, cancer types and treatments. PATIENTS AND METHODS: The files of the 46 829 patients diagnosed with an FPC in the Centre Léon Bérard from 2013 to 2018 were analyzed. Structured data were extracted and electronic patient records were screened using a natural language processing tool, with validation using manual screening of 2818 files of patients. Univariate and multivariate analyses of the incidence of SPC according to patient characteristics and treatment were conducted. RESULTS: Among the 46 829 patients, 1830 (3.9%) had a diagnosis of SPC with a median interval of 11.1 months (range 0-78 months); 18 128 (38.7%) received cytotoxic chemotherapy (CC) and 1163 (2.5%) received ICIs for the treatment of the FPC in this period. SPCs were observed in 7/1163 (0.6%) patients who had received ICIs for their FPC versus 437/16 997 (2.6%) patients receiving CC and no ICIs for the FPC versus 1386/28 669 (4.8%) for patients receiving neither CC nor ICIs for the FPC. This reduction was observed at all ages and for all histotypes analyzed. Treatment with ICIs and/or CC for the FPC are associated with a reduced risk of SPC in multivariate analysis. CONCLUSION: Immunotherapy with ICIs alone and in combination with CC was found to be associated with a reduced incidence of SPC for all ages and cancer types.

[Utility of 18 FDG positon emission tomography in detection of sarcomatous transformation in neurofibromatosis type 1]. / Intérêt de la tomographie par émission de positons au fluorodéoxyglucose 18 dans la détection des neurofibrosarcomes au cours de la neurofibromatose de type 1.

BACKGROUND: The appearance of malignant peripheral nerve sheath tumours (MPNST) marks a critical stage in the course of neurofibromatosis type 1 (NF1). Since the diagnostic criteria are fairly non-specific, histological examination alone can confirm malignancy. We assessed the value of 18 FDG positron emission tomoscintigraphy (PET scan) in screening for such malignant tumours. PATIENTS AND METHODS: Between October 2000 and August 2006, all of our patients with NF1 and suspected MPNST underwent PET scan. Inclusion criteria consisted of clinical signs (increased tumour size or induration, pain) and/or laboratory values. Analysis of PET scan images, based upon determination of tumour/liver binding ratio with a cut-off point of 1.5 times hepatic binding, was used to classify lesions as non-suspect or pathological. In the case of suspect lesions, histological analysis was performed. For non-suspect lesions, patients either underwent monitoring or excision of the lesion where necessary and technically feasible. RESULTS: Thirty-eight patients with 49 tumours were included in the study. In 8 patients, PET scan showed suspect lesions (12 tumours), and histological analysis of these tumours revealed 6 MPNST. In 30 patients (37 tumours) PET scan showed non-suspect binding, and no malignant tumours were demonstrated either on histological examination or after mean follow-up of 33.5 months. PET scan thus demonstrated a sensitivity and negative predictive value of 100%, specificity of 86%, and a positive predictive value of 50%. The ratios of positive and negative probability were respectively 7.14 and 0. DISCUSSION: Our study, to our knowledge the most extensive yet performed, demonstrates the value of PET scan in detecting MPNST, particularly based on its 100% negative predictive value. To date, other than biopsy, no examinations allow diagnosis with any certainty. The literature reports 2 studies analysing the value of PET scan. The first involved 18 NF1 patients with 23 plexiform neurofibromas: of 7 tumours with hyperbinding, 5 were MPNST. The second study concerned 5 NF1 patients with a total of 15 tumours: 7 tumours showed hyperbinding, of which 6 were MPNST. Using the same evaluation criteria, our study yielded comparable results. The negative predictive value of 100% provides a strong argument in favour of a benign tumour. CONCLUSION: Our study confirms the value of PET scan in the detection of NF1 even though false positives require medical-surgical confirmation before any potentially detrimental therapeutic decisions may be made.

[The therapeutic impact of PET-FDG scanning in broncho-pulmonary cancer]. / Impact thérapeutique de l'imagerie TEP-FDG en carcinologie bronchopulmonaire.

BACKGROUND: Because of the expected high performances of scintigraphic scans with [18F]-fluorodeoxyglucose (FDG) not only in diagnostics and but also in therapeutic impact, especially in thoracic oncology, there are a lot of French nuclear medicine departments which will soon be equipped with a positron emission tomograph (PET). MATERIAL AND METHODS: The Nuclear Medicine Department of the Hôpital d'Instructions des Armées du Val-de-Grâce, Paris, led a retrospective study among physicians interested in 338 FDG-PET exams performed between may 2000 and march 2002 in order to compare its own results with international literature concerning four indications for lung cancer: pulmonary nodule or mass malignancy diagnostic, lung carcinoma extension evaluation, therapeutic efficiency, recurrence suspicion. RESULTS: There seems to be no divergence, regarding limitation induced by the not exhaustive analysis of the retrospective study: more than every two FDG-PET exam highly influenced the effective therapy. CONCLUSION: That is why clinical FDG-PET has to be widely developed to investigate lung cancer.

Bone pain palliation with strontium-89 in cancer patients with bone metastases.

Strontium-89 is a pure beta-emitting radioisotope, a chemical analogue of calcium, and it is therefore avidly concentrated by areas of high osteoblastic activity. Selective uptake and prolonged retention at sites of increased bone mineral turnover provide precise bone lesions targeting. 89Sr chloride (commercialised as Metastron) is typically administered in a single 150 MBq parenteral dose. Its radioactive emission poses very little radioprotection concerns. Overall, studies show pain relief in up to 80% of patients, of which 10 to 40% became effectively pain free. The mean duration of palliation was 3-4 months. The mechanism of pain relief is controversial ; it is probably, but not only, related to the absorbed dose in the tumour and bone. There is no clear dose-response relationship. The only reported toxicity is temporary myelosuppression. WBC and platelets should be monitored at least on a weekly basis until they return to baseline. It seems that only patients with a reasonably good general condition stand to benefit from this treatment. In conclusion, systemic radionuclide therapy using 89Sr represents a feasible, safe, effective, well tolerated and cost-effective palliative treatment in patients with refractory bone pain.

Bone pain palliation with 85Sr therapy.

UNLABELLED: The aim of this retrospective study was to evaluate the efficacy of 85Sr in the palliation of metastatic bone pain. 85Sr decays by electron capture with a gamma emission of 514 keV and associated x-ray emissions of 10-15 keV; physical half-life is 64 d. METHODS: Between 1977 and 1992, 119 doses of 85Sr chloride (mean activity 335 MBq [9 mCi]) were intravenously administered to 108 patients with hyperalgic generalized bone metastases from prostatic carcinoma (52 patients), breast carcinoma (41) or other cancers (15). Pain, performance status, blood and urinary excretion values were investigated during follow-up, and survival time was recorded. Strontium bone scans were obtained up to 8 wk after injection to document isotope biodistribution and to estimate absorbed doses. RESULTS: At 12 wk, 72.2% of patients showed significant benefit from treatment, i.e., enhanced quality of life and pain relief; 49.1% became free of pain. These beneficial effects lasted from 1 to 36 mo (mean 4.3 mo). The best symptomatic improvement was seen in patients treated at an early stage of metastatic skeletal disease and in prostate cancer patients. No evidence of a significant dose-response relationship was found in the data analysis. The mean absorbed dose ratio of metastases to marrow was estimated at 8.2. We found no evidence that hematological toxicity was a major problem; however, all patients experienced a reduction in blood counts, especially in platelets. CONCLUSION: Systemic radionuclide therapy using 85Sr is a feasible, effective and well-tolerated palliative treatment in patients with refractory bone pain. We attained at least the same response rate as that reported with bone-seeking beta-emitting radionuclides such as 89Sr. The patients who benefited the most from 85Sr treatment were in an early stage of metastatic disease or had prostate cancer. Our clinical findings could not be linked to either the total injected activity of 85Sr or the estimated absorbed dose delivered to metastases.