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This Report summarizes the proceedings of the 2017 Les Houches workshop onPhysics at TeV Colliders. Session 1 dealt with (I) new developments relevantfor high precision Standard Model calculations, (II) theoretical uncertaintiesand dataset dependence of parton distribution functions, (III) new developmentsin jet substructure techniques, (IV) issues in the theoretical description ofthe production of Standard Model Higgs bosons and how to relate experimentalmeasurements, (V) phenomenological studies essential for comparing LHC datafrom Run II with theoretical predictions and projections for futuremeasurements, and (VI) new developments in Monte Carlo event generators.

Clinical, morphological and immunological studies of human tuberculosis have enabled the spectrum of the disease to he determined. We have investigated the cell-mediated immune responses by means of skin tests and leucocyte migration inhibition to PMD, and the humoral immune responses by means of immunodiffusion and haemagglutination tests. Patients with tuberculosis can be classified into two polar groups-reactive (RR) and un-reactive (UU), the former showing good cell-mediated immunity and little or no antibody formation and the latter poor cellular responses and exuberant antibody production. The inter- mediate forms show characteristics of the neighbouring polar groups. The existence of a spectrum of immune response in tuberculosis, which has long been suspected, is now demonstrated. [ABSTRACT FROM AUTHOR]

Multiparton interactions are a fascinating phenomenon that occur in almost every high-energy hadron-hadron collision yet are remarkably difficult to study quantitatively. In this Letter, we present a strategy to optimally disentangle multiparton interactions from the primary scattering in a collision. That strategy enables probes of multiparton interactions that are significantly beyond the state of the art, including their characteristic momentum scale, the interconnection between primary and secondary scatters, and the pattern of three and potentially even more simultaneous hard scatterings. This opens a path to powerful new constraints on multiparton interactions for LHC phenomenology and to the investigation of their rich field-theoretical structure.

Scenarios with new physics particles feebly interacting with the Standard Model sector provide compelling candidates for dark matter searches. Geared with a set of new experiments for the detection of neutrinos and long-lived particles the Large Hadron Collider (LHC) has joined the hunt for these elusive states. On the theoretical side, this emerging physics program requires reliable estimates of the associated particle fluxes, in particular those arising from heavy hadron decays. In this work, we provide state-of-the-art QCD predictions for heavy hadron production including radiative corrections at next-to-leading order and using parton distribution functions including small- x resummation at next-to-leading logarithmic accuracy. We match our predictions to parton showers to provide a realistic description of hadronisation effects. We demonstrate the utility of our predictions by presenting the energy spectrum of neutrinos from charm hadron decays. Furthermore, we employ our predictions to estimate, for the first time, FASER's sensitivity to electrophilic ALPs, which are predominantly generated in beauty hadron decays., (© The Author(s) 2024.)

We consider subleading power corrections to event shape variables in e + e - collisions at the first order in the QCD coupling α S . We start from the jettiness variable τ 2 and the y 23 resolution variable for the k T jet clustering algorithm and we analytically compute the corresponding cumulative cross section. We investigate the origin of the different power suppressed contributions in the two-jet limit and trace it back to their different coverage of the phase space. We extend our analysis to the case of thrust and of the C -parameter, and we finally discuss a class of observables that depend on a continuous parameter giving different weight to central and forward emissions and we evaluate the corresponding subleading power corrections., (© The Author(s) 2024.)

The production of a top-antitop quark pair in association with a W boson (tt[over ¯]W) is one of the heaviest signatures currently probed at the Large Hadron Collider. Since the first observation reported in 2015, the corresponding rates have been found to be consistently higher than the standard model predictions, which are based on next-to-leading order calculations in the QCD and electroweak interactions. We present the first next-to-next-to-leading order QCD computation of tt[over ¯]W production at hadron colliders. The calculation is exact, except for the finite part of the two-loop virtual corrections, which is estimated using two different approaches that lead to consistent results within their uncertainties. We combine the newly computed next-to-next-to-leading order QCD corrections with the complete next-to-leading order QCD plus electroweak results, thus obtaining the most advanced perturbative prediction available to date for the tt[over ¯]W inclusive cross section. The tension with the latest ATLAS and CMS results remains at the 1σ-2σ level.

We introduce an observable relevant for the determination of the W -boson mass m W at hadron colliders. This observable is defined as an asymmetry around the jacobian peak of the charged-lepton transverse-momentum distribution in the charged-current Drell-Yan process. We discuss the observable's theoretical prediction, presenting results at different orders in QCD, and showing its perturbative stability. Its definition as a single scalar number and its linear sensitivity to m W allow a clean extraction of the latter and a straightforward discussion of the associated theoretical systematics: a perturbative QCD uncertainty of O ( ± 5 ) MeV on m W can be established by means of this observable, relying solely on charged-current Drell-Yan information. Owing to its relatively inclusive nature, the observable displays desirable properties also from the experimental viewpoint, especially for the unfolding of detector effects. We show that a measurement of this observable can lead to a competitive experimental error on m W at the LHC., (© The Author(s) 2023.)

The Drell-Yan process at hadron colliders is a fundamental benchmark for the study of strong interactions and the extraction of electroweak parameters. The outstanding precision of the LHC demands very accurate theoretical predictions with a full account of fiducial experimental cuts. In this Letter we present a state-of-the-art calculation of the fiducial cross section and of differential distributions for this process at third order in the strict fixed-order expansion in the strong coupling, as well as including the all-order resummation of logarithmic corrections. Together with these results, we present a detailed study of the subtraction technique used to carry out the calculation for different sets of experimental cuts, as well as of the sensitivity of the fiducial cross section to infrared physics. We find that residual theory uncertainties are reduced to the percent level and that the robustness of the predictions can be improved by a suitable adjustment of fiducial cuts.

We consider the associated production of a vector or Higgs boson with a jet in hadronic collisions. When the transverse momentum q T of the boson-jet system is much smaller than its invariant mass Q , the QCD perturbative expansion is affected by large logarithmic terms that must be resummed to all orders. We discuss the all-order resummation structure of the logarithmically enhanced contributions up to next-to-leading logarithmic accuracy. Resummation is performed at the differential level with respect to the kinematical variables of the boson-jet system. Soft-parton radiation produces azimuthal correlations that are fully accounted for in our framework. We present explicit analytical results for the resummation coefficients up to next-to-leading order and next-to-leading logarithmic accuracy, that include the exact dependence on the jet radius., (© The Author(s) 2022.)

We consider the simultaneous measurement of the Higgs (p_{t}^{H}) and the leading jet (p_{t}^{J}) transverse momentum in hadronic Higgs-boson production, and perform the resummation of the large logarithmic corrections that originate in the limit p_{t}^{H},p_{t}^{J}≪m_{H} up to next-to-next-to-leading-logarithmic order. This work constitutes the first simultaneous (double differential) resummation for two kinematic observables of which one involves a jet algorithm in hadronic collisions, and provides an important milestone in the theoretical understanding of joint resummations. As an application, we provide precise predictions for the Higgs transverse-momentum distribution with a veto p_{t}^{J}≤p_{t}^{J,v} on the accompanying jets, whose accurate description is relevant to the Higgs precision programme at the Large Hadron Collider.

We present accurate QCD predictions for the transverse momentum ( p ⊥ ) spectrum of electroweak gauge bosons at the LHC for 13 TeV collisions, based on a consistent combination of a NNLO calculation at large p ⊥ and N 3 LL resummation in the small p ⊥ limit. The inclusion of higher order corrections leads to substantial changes in the shape of the differential distributions, and the residual perturbative uncertainties are reduced to the few percent level across the whole transverse momentum spectrum. We examine the ratio of p ⊥ distributions in charged- and neutral-current Drell-Yan production, and study different prescriptions for the estimate of perturbative uncertainties that rely on different degrees of correlation between these processes. We observe an excellent stability of the ratios with respect to the perturbative order, indicating a strong correlation between the corresponding QCD corrections., (© The Author(s) 2019.)

We present a determination of the parton distribution functions of the proton in which NLO and NNLO fixed-order calculations are supplemented by NLL x small- x resummation. Deep-inelastic structure functions are computed consistently at NLO+NLL x or NNLO+NLL x , while for hadronic processes small- x resummation is included only in the PDF evolution, with kinematic cuts introduced to ensure the fitted data lie in a region where the fixed-order calculation of the hard cross-sections is reliable. In all other respects, the fits use the same methodology and are based on the same global dataset as the recent NNPDF3.1 analysis. We demonstrate that the inclusion of small- x resummation leads to a quantitative improvement in the perturbative description of the HERA inclusive and charm-production reduced cross-sections in the small x region. The impact of the resummation in our fits is greater at NNLO than at NLO, because fixed-order calculations have a perturbative instability at small x due to large logarithms that can be cured by resummation. We explore the phenomenological implications of PDF sets with small- x resummation for the longitudinal structure function F L at HERA, for parton luminosities and LHC benchmark cross-sections, for ultra-high-energy neutrino-nucleus cross-sections, and for future high-energy lepton-proton colliders such as the LHeC.

We present a new set of parton distributions, NNPDF3.1, which updates NNPDF3.0, the first global set of PDFs determined using a methodology validated by a closure test. The update is motivated by recent progress in methodology and available data, and involves both. On the methodological side, we now parametrize and determine the charm PDF alongside the light-quark and gluon ones, thereby increasing from seven to eight the number of independent PDFs. On the data side, we now include the D0 electron and muon W asymmetries from the final Tevatron dataset, the complete LHCb measurements of W and Z production in the forward region at 7 and 8 TeV, and new ATLAS and CMS measurements of inclusive jet and electroweak boson production. We also include for the first time top-quark pair differential distributions and the transverse momentum of the Z bosons from ATLAS and CMS. We investigate the impact of parametrizing charm and provide evidence that the accuracy and stability of the PDFs are thereby improved. We study the impact of the new data by producing a variety of determinations based on reduced datasets. We find that both improvements have a significant impact on the PDFs, with some substantial reductions in uncertainties, but with the new PDFs generally in agreement with the previous set at the one-sigma level. The most significant changes are seen in the light-quark flavor separation, and in increased precision in the determination of the gluon. We explore the implications of NNPDF3.1 for LHC phenomenology at Run II, compare with recent LHC measurements at 13 TeV, provide updated predictions for Higgs production cross-sections and discuss the strangeness and charm content of the proton in light of our improved dataset and methodology. The NNPDF3.1 PDFs are delivered for the first time both as Hessian sets, and as optimized Monte Carlo sets with a compressed number of replicas., (© The Author(s) 2017.)

We consider the production of a pseudo-scalar particle A at the LHC, and present accurate theoretical predictions for its inclusive cross section in gluon fusion. The prediction is based on combining fixed-order perturbation theory and all-order threshold resummation. At fixed order we include the exact next-to-next-to-leading order (NNLO) plus an approximate next-to-next-to-next-to-leading order (N[Formula: see text]LO[Formula: see text]) which is based on the recent computation at this order for the scalar case. We then add threshold resummation at next-to-next-to-next-to leading logarithmic accuracy (N[Formula: see text]LL[Formula: see text]). Various forms of threshold resummation are considered, differing by the treatment of subleading terms, allowing a robust estimate of the theoretical uncertainties due to missing higher orders. With particular attention to pseudo-scalar masses of 200 and 750 GeV, we also observe that perturbative convergence is much improved when resummation is included. Additionally, results obtained with threshold resummation in direct QCD are compared with analogous results as computed in soft-collinear effective theory, which turn out to be in good agreement. We provide precise predictions for pseudo-scalar inclusive cross section at 13 TeV LHC for a wide range of masses. The results are available through updated versions of the public codes ggHiggs and TROLL.

We present an unbiased determination of the charm content of the proton, in which the charm parton distribution function (PDF) is parametrized on the same footing as the light quarks and the gluon in a global PDF analysis. This determination relies on the NLO calculation of deep-inelastic structure functions in the FONLL scheme, generalized to account for massive charm-initiated contributions. When the EMC charm structure function dataset is included, it is well described by the fit, and PDF uncertainties in the fitted charm PDF are significantly reduced. We then find that the fitted charm PDF vanishes within uncertainties at a scale [Formula: see text] GeV for all [Formula: see text], independent of the value of [Formula: see text] used in the coefficient functions. We also find some evidence that the charm PDF at large [Formula: see text] and low scales does not vanish, but rather has an "intrinsic" component, very weakly scale dependent and almost independent of the value of [Formula: see text], carrying less than [Formula: see text] of the total momentum of the proton. The uncertainties in all other PDFs are only slightly increased by the inclusion of fitted charm, while the dependence of these PDFs on [Formula: see text] is reduced. The increased stability with respect to [Formula: see text] persists at high scales and is the main implication of our results for LHC phenomenology. Our results show that if the EMC data are correct, then the usual approach in which charm is perturbatively generated leads to biased results for the charm PDF, though at small x this bias could be reabsorbed if the uncertainty due to the charm mass and missing higher orders were included. We show that LHC data for processes, such as high [Formula: see text] and large rapidity charm pair production and [Formula: see text] production, have the potential to confirm or disprove the implications of the EMC data.

Purpose: We evaluated the antiemetic efficacy of tropisetron, a 5-HT3 receptor antagonist, during its compassionate use in children with malignant disease who during previous chemotherapy cycles experienced emesis refractory to metoclopramide-based treatments., Patients and Methods: Tropisetron was given to 15 children (eight boys and seven girls 18 months to 18 years of age) with miscellaneous neoplasms. Generally 5 mg/day of tropisetron was administered i.v. the first day of cisplatin-based chemotherapy and i.v. or orally each subsequent day of chemotherapy. The dose of tropisetron was reduced to 2 mg/day in children < 2 years of age and weighing < 20 kg., Results: Vomiting was well controlled (no more than two episodes per day) on 118 of the 184 days of treatment with tropisetron (64%). No clinically important variations were observed in blood pressure, heart rate, body temperature, or electrocardiographic findings attributable to tropisetron. Transient, mild to moderate side effects (headache, constipation, abdominal pain, diarrhea) occurred in five patients on 11 of the 184 days of tropisetron treatment (6%)., Conclusion: The results obtained during compassionate use of tropisetron confirm that it is a valid, safe, and manageable antiemetic for the treatment of pediatric patients.

One hundred and twenty-one consecutive patients with monostotic Ewing's sarcoma (ES) were treated according to three consecutive combined modality programs from 1974 to 1986. Their 3-year progression free survival (PFS) rate from diagnosis of 59% was identical to the event free survival (EFS) rate, since all the 50 events occurring within 3 years from diagnosis were tumor recurrences. Primary tumor was treated with radiotherapy in 75 cases, surgical resection plus radiotherapy in 38, and radical surgery in 8. Chemotherapy was given to all patients and each program included adriamycin, vincristine, and cyclophosphamide +/- dactinomycin. Median follow-up was 12 years, ranging from 6 to 19 years. The PFS rate decreased to 49% at 6 years and plateaued at 46% after the 7th year from diagnosis, even though some relapses were observed as late as 14 years from diagnosis. Second malignancies developed in 7 patients free from progressive ES and were represented by osteogenic sarcoma in previously irradiated bone in 4 cases and by breast carcinoma in 3. No other event but tumor relapse or second malignancy occurred in this series. EFS rate was 47% at 6 years and 39% at 12 years, further decreasing in the following years because of a number of late events. A continuous PFS longer than 7 years may be consistent with cure in the majority of patients with monostotic ES. However, these patients should be followed indefinitely because of risk of second malignancies.

The treatment programme (regimen I) we designed in 1982 for advanced Burkitt's lymphoma was modified in 1986 as regimen IIA and IIB for patients presenting without or with bone marrow (BM) and/or nervous system involvement, respectively. Following a 5-week course of cytoreductive chemotherapy, including vincristine (VCR), cyclophosphamide (CPM), doxorubicin (DXR), high-dose methotrexate (HDMTX) and intrathecal methotrexate and cytarabine (ARAC), high-dose ARAC and cisplatin were given as a 4-day continuous infusion. Regimen I continued with an additional 3-week course including VCR, CPM, DXR and HDMTX, which was omitted in regimen IIA. In regimen IIB the initial cytoreductive chemotherapy was complemented by adding etoposide and increasing HDMTX doses, and by modifying the high-dose ARAC administration modality and was followed, once the bone marrow had recovered, by ifosfamide that concluded the programme. A total of 44 children (22 in regimen I and 22 in regimens IIA and IIB) were treated, with an overall response rate of 98%. 4 patients died as a result of treatment related complications. Survival, progression-free and event-free survival rates were 73, 70 and 63%, respectively, for regimen I, and 82, 90 and 82%, respectively, for regimen IIA and IIB. A short chemotherapeutic regimen, using alternating phase-specific and non-specific agents, is able to cure the majority of patients with advanced Burkitt's lymphoma.

Twenty-four consecutive patients with nondysgerminomatous germ cell tumor of the ovary were treated after surgery with cisplatin, vinblastine, and bleomycin (PVB regimen). The cycle was repeated every 3 weeks for three to five courses. Fourteen patients had endodermal sinus tumor, and 10 had mixed germ cell tumors. Stage of disease (FIGO, 1986) was as follows: stage I, 6; stage IIc-IV, 17; and recurrence, 1 patient. All patients were monitored by alpha-fetoprotein and human chorionic gonadotropin. Only 1 patient had received previous chemotherapy. All 5 patients without residual disease and with negative marker levels in which PVB was used as adjuvant treatment were free of disease for a median duration of 59 months from the start of PVB. Of the 19 patients with measurable disease (evident disease or positive marker levels), complete remission was obtained in 16 (84%), but 5 of these relapsed. Therefore, treatment with PVB failed in 8 out of 19 patients (42%) with measurable disease. Toxicity was evident, but no patient died of it. Menses were regular in 11 patients whose initial surgery was conservative. PVB regimen is an effective but not a satisfactory treatment. The considerable failure rate of PVB treatment suggests the investigation of other regimens.

A method of hypofractionated accelerated radiotherapy (3 weekly fractions of 6 Gy over 2 weeks to a total tumor dose of 36 Gy) was used as single modality in 14 patients with osteogenic sarcoma for palliative treatment of the primary tumor site (six cases) or skeletal metastases (15 sites). A durable response, radiologically assessed, was obtained in 17 of the 21 (81%) irradiated sites. When this irradiation modality was combined with chemotherapy, to treat patients presenting with synchronous metastases (eight cases) or refusing amputation (five cases), a radiologically assessed response was observed in 12 of 13 (92%). In no case did a local recurrence occur before surgery or death because of progressive disease elsewhere. Of the seven patients who later had to undergo ablative surgery, a 100% and 95% tumor necrosis was observed in 6 and 1, respectively. Because of intralesional resection of primary osteogenic sarcoma after preoperative chemotherapy, seven additional patients were irradiated. None recurred at the level of the primary site. Although effective in inducing remission of osteogenic sarcoma, this irradiation method produced severe damages to normal tissues in a high proportion of patients.

Our experience with [131I]metaiodobenzylguanidine (131I-MIBG) therapy in a 10 year old boy is reported. At disease onset, in May 1988, this boy presented a large mass in the upper left abdominal quadrant, which was resected with a histopathological diagnosis of extra-adrenal malignant pheochromocytoma (paraganglioma). He subsequently underwent two further surgical resections and chemotherapy. When 131I-MIBG therapy was started, in June 1990, skeletal and abdominal metastases were present. These localizations were revealed by 131I-MIBG scans and confirmed by x-ray examination. At present 6 courses of therapy have been performed with a cumulative activity of 29.6 GBq. Side-effects have been limited to vomiting and mild thrombocytopenia, lasting 2 weeks during the second course of therapy. After 15 months of therapy, a progressive reduction of MIBG uptake, coupled with a stabilization of the lythic lesions, has been observed.

Our experience with palliative [131I]metabenzylguanidine (131I-MIBG) therapy in 7 patients (6 children and 1 adult) affected by advanced neuroblastoma is reported. All patients (classified as IV stage) showed a progression following initial intensive therapy, including chemotherapy and, in some cases, hemi-body irradiation and surgery for their primary tumor. 131I-MIBG activity ranged for a single course between 2.77 GBq to 5.55 GBq on the basis of age, intensity of uptake, and the hematological assessment. Four patients received only one course of therapy due to progressive disease (2), early death (1) or persistent thrombocytopenia unrelated to 131I-MIBG therapy (1). Two patients received two courses and showed a partial response lasting 4 months and stable disease lasting 3 months respectively. Therapy was thereafter discontinued due to progression. One patient received 4 courses of therapy (cumulative activity = 19.61 GBq) in 5 months. A partial response for 9 months in the bone metastases was documented, but the therapy was discontinued due to persistent thrombocytopenia (58,000 plts/microL) lasting 4 months. Thrombocytopenia was the major side-effect, occurring in 5/7 patients over 8 courses of therapy for a mean period of 37 days (7-120 d). Thus, in our experience thrombocytopenia is the major factor limiting the therapeutic effect of 131I-MIBG therapy in palliative treatment.

In sarcoidosis the excess of calcitriol of extrarenal origin induces changes in calcium metabolism (CM), specifically hypercalciuria and less often hypercalcemia. We report the results of the study of CM in 44 sarcoidosis patients (mean age 43.7 +/- 11 years, M +/- SD, 21 males). 25% were on steroid therapy at the time of the tests. 34% of the patients had hypercalciuria, this figure rose to 39% if only untreated patients were considered. Hypercalcemia was found in only 2.2%. Chronic forms and extrathoracic involvement (mostly skin) were more frequent in the hypercalciuric patients than in the normocalciuric.

In sera of 38 patients with sarcoidosis, assayed for antiviral antibody to Rubella, Measles, Cytomegalovirus (CMV), adenovirus, Epstein-Barr virus (EBV), human immunodeficiency virus (HIV), different incidence of seropositivity have been found, according to the virus assayed. Interestingly all patients were seropositive to rubella virus with high titres compared to data obtained from normal age matched population. These data indicate that in Sarcoidosis an altered antibody response of post-primary type can be found.

The results are reported of an immunological study conducted on 37 cases of active sarcoidosis, in which some in vivo and in vitro tests related to the cell-mediated immunitary response were effected. The results are discussed, with relation to the clinical use of the immunological tests adopted, and their immunopathogenetic significance. In particular, the occurrence of false-positive and false-negative results in the in vitro Kveim antigen test (LMT) using the antigen preparations currently available, limit its use in clinical practice.

Bronchoalveolar lavage (BAL) was performed in a group of 25 patients with pulmonary sarcoidosis in order to monitor variations in alveolar lymphocytes (AL) in comparison to the clinical evolution of the disease. Two BAL were performed in each patient, the second 6-12 months after the first (8.9 +/- 3, M +/- SD). Twelve patients were classified as improved and 13 as unimproved on the basis of a score of changes in the clinical picture, x-ray, respiratory function, immunological and biochemical tests. There was a significant decrease (p less than 0.001) of the percentage of AL in 66% of cases in the improved group, but not in the unimproved group, where, on the contrary, it was possible to observe an increase in the percentage of AL in 46% of these cases (n.s.). In 9 of 11 patients followed for 1-5 years with at least 3 BAL, AL behaviour correlated with clinical evolution. On the basis of the parameters studied, it was possible to show a correlation between lymphocytes, alveolitis and clinical evolution, especially in patients with an improved course. While a single BAL does not seem to be sufficient to show the course of the disease, repeated long-term washings allow a more accurate staging of sarcoidosis and can give early warning of relapses even when the conventional parameters (clinical, radiological and functional) are unchanged. Our aim was to look for a simpler parameter, which could be used routinely by even unspecialized laboratories, who are not able to type lymphocytes.

Twelve children younger than 16 years affected by undifferentiated nasopharyngeal carcinoma (NPC) with advanced primary tumor (T3, T4) were treated with chemotherapy consisting of Adriamycin (ADM [doxorubicin; Adria Laboratories, Columbus, OH]), vincristine (VCR), and cyclophosphamide (CYC), and radiotherapy. Preradiation chemotherapy produced partial responses in eight of ten evaluable patients. Eleven of 12 patients achieved a complete response following radiotherapy. The actuarial 3-year continuous relapse-free survival (CRFS) was 75%. This represents a significant improvement when compared with the 8% rate obtained in a previous series of patients treated with radiotherapy either with or without adjuvant CYC.

Fifteen patients with metastatic osteogenic sarcoma (OS) were treated with a combination of Vincristine (1.4 mg/m2), high-dose Methotrexate (8 g/m2), and Cisplatin (120 mg/m2 as a 72-h continuous infusion). The overall response rate was 66% [5 complete response (CR) and 5 partial response (PR)]. Four of the six patients not previously treated had a CR. Toxicity from this regimen was moderate and never life-threatening. In no case was impairment of the renal function observed, and the clearance of high-dose Methotrexate was never delayed.

Leucocyte inhibition migration test (LMT) with BCG and PPD was applied in pulmonary tuberculosis, lung cancer and sarcoidosis. No significant differences were noticed in the results obtained with each of the two antigenic materials; nevertheless, one case lobectomized of lung cancer successively treated with chemiotherapie and immunostimulation with BCG presented LMT positivity with BCG and negativity with PPD. The unpublished results of the former investigations carried out with brute tuberculin (LMT) on patients with pulmonary tuberculosis are here reported no significant difference was noticed between the results obtained with brute tuberculin, and the results with PPD. The still unsettled problem presented by the lack of inhibition in the presence of PPD in leucocyte migration test in patients with areactive (AA) and intermediate areactive (AI) tuberculosis is also briefly discussed. Finally, the existence of a dissociation between the cutaneous delayed test and the in vitro test for the detection of cellular sensibilisation is confirmed even when LMT is applied either in the presence of BCG or of PPD.