Immune checkpoint inhibitor rechallenge in patients who previously experienced immune-related inflammatory arthritis: a multicentre observational study

OBJECTIVE

Another course of immune checkpoint inhibitors (ICIs) is often considered in patients with cancer progression and previous immune-related adverse events, including inflammatory arthritis (ICI-IA), but there are limited data regarding safety of ICI rechallenge in this setting. We aimed to assess the rate and clinical features associated with ICI-IA flare/recurrence on ICI rechallenge.

METHODS

We conducted a multicentre observational study including cancer patients with ICI-IA who started a second course of ICI more than 3 months after ICI discontinuation in four French university hospitals. Primary outcome was the frequency of ICI flare/recurrence after ICI rechallenge.

RESULTS

Twenty-three patients were included. At the time of ICI rechallenge, 18 patients reported no symptoms of ICI-IA (78%) and 5 had grade 1 (22%), 11 patients (48%) were not receiving any ICI-IA treatment, 11 (48%) were still on prednisone, 2 (9%) were on conventional synthetic disease-modifying antirheumatic drugs and 1 (4%) on anti-IL-6. ICI-IA flare/recurrence occurred in 12 patients (52%) with a median time of 1 month after ICI rechallenge. ICI-IA phenotype, disease activity and ICI-IA treatment at the time of ICI rechallenge did not differ according to ICI-IA flare/recurrence status.

CONCLUSION

In this first observational study of ICI-IA patients rechallenged with ICI, about half of the patients experienced ICI-IA flare/recurrence with a similar phenotype but occurring earlier than the initial ICI-IA, warranting close monitoring during the first month of retreatment. Risk of flare did not differ according to baseline immunosuppressive treatment at the time of rechallenge.

Activity and tolerability of maintenance avelumab (AVE) immunotherapy after first-line platinum-based polychemotherapy in patients (pts) with locally advanced or metastatic squamous cell penile carcinoma: Initial results of PULSE study

8

Background: Metastatic squamous cell penile carcinoma (mSCPC) is an orphan disease with a virally induced oncogenesis. PD-L1 expression rate is around 60% with a strong correlation between PD-L1 in the primary tumour and metastases. The first line systemic treatment relies on platinum-based chemotherapies with a median progression free survival and overall survival around 7.5 and 16 months (mo), respectively. Immunotherapies targeting PD-1/PD-L1 axis are effective in other squamous cell or HPV related cancers. Methods: PULSE is a national prospective multicenter open label single arm phase II trial. Thirty-two pts will be enrolled after a radiological assessment showing a non-progressive disease after 3 to 6 cycles of a first line platinum-based polychemotherapy. Pts will receive AVE injections 10mg/kg every two weeks until progression or unacceptable toxicity. The primary endpoint will be the progression free survival (PFS) from AVE initiation according to RECIST v1.1 criteria. Key secondary endpoints will include, overall survival, safety. Here we report the results of the first interim analysis (IA). Results: From September 2019 to October 2022, 14 pts has been enrolled. Within the 9 first patients involved for the IA the median age was 69.9 years; 89% of pts had an ECOG 0-1. Of them, 1 patient and 8 pts had stage 3 and 4 disease at chemotherapy initiation, respectively. Median follow-up was 5.8 [2.3-17.2] mo. Chemotherapy regimens were triplets for 5 pts (56%), containing cisplatin for 56% and a taxane for all pts. Median duration of chemotherapy was 3.7 mo [1.2; 11.7]. At AVE initiation, 5 pts (56%) had partial or complete response and 4 pts (44%) had stable disease. Median duration of AVE was 3.7 mo with a majority (83%) of discontinuation linked to disease progression. Survival data are shown in the table. No new safety signal was identified. Conclusions: PULSE is the first prospective trial exploring avelumab maintenance activity in mSCPC. After the IA the DSMB have recommended to pursue the study based on these promising results. Updated results with additional patients, longer follow-up and ancillary explorations with biomarkers analysis will be presented at the meeting. Clinical trial information: NCT03774901 . [Table: see text]

An Evaluation of Cabozantinib for the Treatment of Renal Cell Carcinoma: Focus on Patient Selection and Perspectives

Cabozantinib is an oral tyrosine kinase inhibitor (TKI) with activity against several receptors involved in the angiogenesis pathway, including vascular endothelial growth factor receptor (VEGFR), c-MET and AXL. The antiangiogenic properties of cabozantinib led to its use as a monotherapy for the treatment of metastatic renal cell cancer (RCC), and quickly resulted in this treatment becoming part of the standard of care for these tumors. Since the advent of immune checkpoint inhibitors (ICIs), new standards of care have emerged in first-line settings, involving dual ICI or ICI–VEGF-TKI (including ICI–cabozantinib) combination treatments, and leading to a more complex algorithm of care. Cabozantinib remains an option in second-line settings and is still a first-line standard of care treatment in cases where the use of ICIs is contraindicated. This review focuses on the selection of patients who may benefit most from cabozantinib therapy, including those with bone and brain metastases and those with a non-clear cell RCC histology. The need to consider disease-related symptoms, comorbidities, age, drug interactions and biomarker analyses in the choice of therapeutic strategy is also highlighted. Finally, the perspectives for the use of cabozantinib in RCC treatment are discussed.

CIMUC: Chemotherapy following Immune checkpoints inhibitors in patients with locally advanced or metastatic urothelial carcinoma (la/mUC)

492

Background: Immune checkpoints inhibitors (ICIs) have recently changed therapeutic landscape of la/mUC. Recent studies suggested an improvement of response to salvage chemotherapy (CT) after ICIs in several cancer types including urothelial carcinoma. We assumed that efficacy of CT rechallenge after ICIs may be improved compared to second-line CT without previous ICIs in patients (pts) with la/mUC. Methods: CIMUC is a French multicentric retrospective study including all pts with la/mUC initiating second or third-line CT from January 1st 2015 to June 30th 2020. Two groups of pts were defined: pts in group 1 (G1) were treated with a second-line CT without previous ICIs; pts in group 2 (G2) were treated with third line CT after ICIs. Primary endpoint was objective response rate (ORR: proportion of patients with complete or partial response, according to RECIST 1.1 criteria) in G2 versus G1. Secondary endpoints were progression-free survival (PFS), defined as time from initiation of second or third-line CT to disease progression or death from any cause, and toxicities. This study is supported by the French Genito Urinary Group (GETUG). Results: 553 pts were included. Baseline characteristics of the 2 groups are summarized in the Table. ORRs were 31% (95%CI [26.5-35.5]) and 29.2% (95%CI [21.9-36.6]) respectively in G1 and G2, without statistically significant difference (p=0.617), even after adjustment for Bellmunt risk factors (p=0.3214). In subgroups analysis, no difference in ORR was observed by type of CT (platinum or taxanes), duration of response (DOR) to first-platinum-based CT (< 12 months or ≥ 12 months) and FGFR-status. We did not identify any predictive factor of OR in G2 in multivariate analysis. Median PFS were 4.6 months (95%CI [3.88; 5.06]) and 4.86 months (95%CI [4.11; 5.45]), respectively in G1 and G2. Grade 3/4 hematologic toxicity occurred in 35% and 22.4%, respectively in G1 and G2. Conclusions: While ORR was not superior in G2 versus G1, pts derive comparable benefit in a further line of treatment (G2) in terms of ORR and PFS. Despite limits inherent to any retrospective study, CIMUC represents one of the largest retrospective studies in this setting.[Table: see text]

Primary urethral cancer: A GETUG French nationwide cohort study

430

Background: Primary urethral cancer (PUC) is a rare and heterogeneous malignancy. Due to its scarcity, little data are available on the optimal treatment sequence and survival, especially in metastatic patients. Methods: Data from patients diagnosed with a PUC between 01/01/2000 and 12/31/2018 were retrospectively collected from nine French referral centers. Survival rate were estimated with the Kaplan-Meier method and prognostic factors were analyzed using the Cox proportional hazards model and the log-rank test. In order to increase the statistical power of survival analysis in the metastatic stage, patients with synchronous and metachronous metastatic disease were pooled. Results: We identified 44 (62%) males and 27 (38%) females with a PUC. The most frequent histological types were urothelial carcinomas (40.0%), squamous cell carcinomas (34.3%) and adenocarcinomas (14.3%). Twenty-five (35.2%) patients were diagnosed at a localized stage (≤ T2, N0, M0); 35 (49.3%) at a locally advanced stage (≥ T3 or ≥ N1, M0) and 11 (15.5%) at a distant stage (M1). Twenty-seven patients had a metachronous metastatic cancer. Multimodality therapy was used in 24.0% and 57.1% of the patients with a localized and locally advanced disease, respectively. In the entire cohort, median overall survival (OS) was 52.5 months (IC95% 32.2 – 64.1) and stage at diagnosis was a predictor of OS (p < 0.0001). For the 60 patients with a non-metastatic disease, 39 (65%) had a recurrence or were dead and the median disease-free survival (DFS) was 21.2 months (IC95% 16.8 – 34.5). Nodal involvement was the only factor associated with DFS (HR: 2.03, p = 0.0390). Multimodal treatment compared with unimodal treatment was not significantly associated with DFS (HR: 1.22, p = 0.5419). Regarding survival of the 38 metastatic patients, the median OS was 15.2 months (IC95% 8.2 – 23.5) and the median progression-free survival was 6.4 months (IC95% 4.4 – 9.8). Conclusions: This retrospective study showed an important heterogeneity in terms of histology, stage at diagnosis, and treatment of PUC. In this cohort, the multimodal approach did not show any improvement in survival of non-metastatic patients. This study is one of the few to describe the survival in metastatic patients.

Thyroid-like follicular renal cell carcinoma with sarcomatoid differentiation and aggressive clinical course: a case report confirming EWSR1::PATZ1 fusion

Thyroid-like follicular renal cell carcinoma (TFRCC) is rare, with <50 cases reported in the litterature. Recently, Al-Obaidy et al. described recurrent EWSR1::PATZ1 fusions in TFRCC, supporting its classification as an independent entity¹ . We report herein a diagnostically challenging case of TFRCC with sarcomatoid differentiation, aggressive clinical course and presence of an EWSR1::PATZ1 fusion.

Rechallenge of nivolumab in metastatic renal cell carcinoma, an ambispective multicenter study (RENIVO)

330

Background: Immune checkpoint inhibitors (ICIs) in combination with another ICI or an antiangiogenic targeted therapy have been approved for frontline therapy in metastatic renal cell carcinoma (mRCC). However, progression disease (PD) often occurs and subsequent therapies are needed. Rechallenge of ICI may then be an option, but there is a lack of data regarding this strategy. Methods: This ambispective multicenter study included patients who received a rechallenge of Nivolumab (ICI-2) between January 2014 and September 2020, after a first-ICI therapy (ICI-1), regardless of the reason of the discontinuation. Patients could have either a non-ICI therapy or have a prolonged free-interval (≥ 12 weeks) between ICI regimens. Those with ongoing rechallenge at inclusion were followed prospectively. Primary endpoint was investigator-assessed best ORR. Results: 45 rechallenges were included from 16 centers. Median age was 60 years (range, 42-90), 64% were male. Most of them had clear cell histology (91%) and a Fuhrman or ISUP grade ≥ 3 (80%). Single-agent Nivolumab and Nivolumab-Ipilimumab association were used in 78% and 11% during ICI-1 and in 93% and 7% during ICI-2, respectively. Discontinuation for PD, toxicity or clinical decision occurred in 49%, 27% and 24% for ICI-1 and in 94%, 3% and 3% for ICI-2, respectively. The ORR were 51% (n = 23) at ICI-1 and 16% (n = 7) at ICI-2. One patient had a complete response during both ICI-1 and ICI-2 and two had a partial response at ICI-2 although they had PD as best ICI-1 response. After a median follow-up of 14.9 months (mo), median duration of response for ICI-2 was 5.1 mo (95% CI, 2.7-not reached [NR]). For ICI-1 and ICI-2: median progression-free survival (PFS) was 11.4 mo (95% CI, 9.8-23.5) and 3.5 mo (95% CI, 2.8-9.7); median overall survival was NR (95% CI, 37.8-NR) and 24 mo (95% CI, 9.9-NR). Poor prognostic factors for PFS at ICI-2 were Eastern Cooperative Oncology Group Performance Status (ECOG PS) ≥ 2, presence of liver metastases, inflammatory syndrome and PFS under ICI-1 > 6 months. Grade ≥ 3 immune-related adverse events occurred in 24% (n = 11) during ICI-1 but only in 4% (n = 2) during ICI-2. There was no treatment-related death. Conclusions: Our study suggests that resumption of ICI with Nivolumab has a moderate efficacy in mRCC and acceptable tolerance. Predictive factors of response are needed to propose this strategy to selected mRCC patients. Larger prospective cohorts are needed to confirm these results. [Table: see text]

Management of Immune Checkpoint Inhibitor Toxicities

Immune checkpoint inhibitors (ICIs) have radically changed the clinical outcome of several cancers with durable responses. CTLA-4 (cytotoxic T lymphocyte antigen-4), PD-1 (programmed cell death protein 1) or PDL-1 (programmed cell death ligand protein 1) represent ICIs that can be used as monotherapy or in combination with other agents. The toxicity p\rofiles of ICIs differ from the side effects of cytotoxic agents and come with new toxicities like immune-related adverse events. Typically, these toxicities occur in all organs. However, the main organs affected are the skin, digestive, hepatic, lungs, rheumatologic, and endocrine. Most of the immune toxicity that occurs is low grade but some more severe toxicities can occur that require a rapid diagnosis and appropriate treatment. The recognition of symptoms by physicians and patient is necessary to resolve them rapidly and adapt treatment to allow the toxicity to resolve.

Open-label randomized multi-center phase 2 study: gemcitabine cisplatin plus avelumab or gemcitabine cisplatin as first-line treatment of patients with locally advanced or metastatic urothelial bladder carcinoma: GCisAve

BACKGROUND

The standard treatment in first line of advanced or metastatic urothelial bladder cancer (MBC) is the association of Gemcitabine and Cisplatin (GC). Avelumab, an anti-PD-L1 agent, has recently demonstrated efficacy. The objective is to evaluate the combination of these 3 agents.

METHODS

This phase II randomized open-label study, evaluated if GC-avelumab increases response rate and duration of response of patients in 1^st line treatment for MBC compared to GC. Severe toxicities should not overlap and be acceptable. The two co-primary end points are the objective response rate and the incidence of severe toxicity after six cycles of treatment. The study will recruit 90 participants, randomized in two arms (1:2), GC (gemcitabine 1 000 mg/m²/j, J1,J8, Cisplatine 70 mg/m², J1 = J21), and GC-avelumab (10 mg/Kg/3 semaines). Randomization will be stratified on Karnofsky status (≥ 80 % vs. < 80 %) and visceral vs non visceral metastases. The duration of the inclusion period is 24 months, with a duration of participation of each patient of 18 months and a total study duration of 42 months.

DISCUSSION

If both efficacy and safety of the association of GC+avelumab are in the range of acceptable through this specific study design, this will support a subsequent randomized phase III study comparing both arms with an overall survival end-point. In addition, the evaluation of predictive parameters to be confirmed (e.g. the impact of tumor PD-L1 expression) or other immunological parameters, may support a selection of the population. NCT number : NCT03324282.

Clinical outcome after progressing to frontline and second-line Anti-PD-1/PD-L1 in advanced urothelial cancer

BACKGROUND

Immune checkpoint inhibitors (ICIs) are approved for first-line (cisplatin unfit, PD-L1+) and platinum-refractory urothelial carcinoma (UC). Still, most patients experience progressive disease (PD) as the best response. Although higher response rates to subsequent systemic treatment (SST) have been described, post-PD outcome data are scarce.

OBJECTIVE

To examine the outcome of UC patients who received SST and no SST after progressing to ICIs.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective analysis of UC patients progressing to frontline or later-line anti-PD-1/PD-L1 therapy in 10 European institutions was conducted between March 2013 and September 2017.

INTERVENTION

Post-PD management as per standard practice.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Overall survival (OS) was analyzed with a Kaplan-Meier model. Cox regression was used for multivariate analysis (MV). Impact of SST on OS was examined with a time-varying covariate model.

RESULTS AND LIMITATIONS

A total of 270 UC patients with PD to ICIs (69 frontline, 201 later line) were analyzed. Of the patients, 57% of frontline-ICI-PD and 34% of later-line-ICI-PD patients received SST, and SST had an impact on OS in MV (frontline: hazard ratio [HR] 0.22, 95% confidence interval [CI] 0.10-0.51, p <  0.001; later line: HR 0.22, 95% CI 0.13-0.36, p <  0.001). In the frontline-ICI-PD group, median OS with and without SST was 6.8 mo (95% CI 5.0-8.6) and 1.9 mo (95% CI 0.9-3.0), respectively. High disease burden (three or more metastatic sites: HR 2.49, p =  0.03; simultaneous liver/bone metastases: HR 3.93, p =  0.03) predicted worse survival. In later-line-ICI-PD group, response to ICIs (HR 0.37, p =  0.03), longer exposure to ICIs (HR 0.89, p =  0.002), and bone metastasis (HR 2.42, p <  0.001) predicted survival. The retrospective nature of this study and a lack of certain parameters limit the interpretation of our analysis.

CONCLUSIONS

Patients progressing to frontline ICIs are at risk of early death, excluding them from experiencing potential benefit from chemotherapy PATIENT SUMMARY: Our analysis suggests that outcomes after failing immunotherapy are poor, particularly in UC patients who received no prior chemotherapy.

[Carbon dioxide laser treatment of genital intraepithelial neoplasia: A retrospective study]

INTRODUCTION

Genital intraepithelial neoplasias (IEN) are precursors of squamous cell carcinoma. The ideal treatment must be efficacious, conservative and well-tolerated. CO2 laser is one of the recommended therapies, but its efficacy and safety have not been extensively studied.

PATIENTS AND METHODS

This was a retrospective single-center study. Sixteen patients (8 women and 8 men) treated with CO2 laser for genital IEN, whether high-grade or differentiated, were included. Surgical lateral margins of 3 to 5mm were taken macroscopically during treatment. The CO2 laser session, assessment of therapeutic response and follow-up were undertaken by a dermatologist at the University Hospital of Caen.

RESULTS

The mean patient age was 68.1 years and mean follow-up was 52.7 months (5-130). Lesions were isolated in 87.5% of patients. The recurrence rates of genital intraepithelial neoplasia after CO2 laser treatment were 58% for women and 40% for men. No impact on quality of life or on sexual activity was reported in over 90% of patients.

CONCLUSION

Whatever the treatment recommended for intraepithelial neoplasia, recurrence is frequent. CO2 laser is an effective and well-tolerated conservative therapeutic option. It enables rapid clinical remission, but as with all currently available treatments, long-term dermatologic follow-up remains necessary.

Dilemmas caused by endogenous pararetroviruses regarding the taxonomy and diagnosis of yam (Dioscorea spp.) badnaviruses: analyses to support safe germplasm movement

The discovery of endogenous pararetroviral sequences (EPRVs) has had a deep impact on the approaches needed for diagnosis, taxonomy, safe movement of germplasm and management of diseases caused by pararetroviruses. In this article, we illustrate this through the example of yam (Dioscorea spp.) badnaviruses. To enable progress, it is first necessary to clarify the taxonomical status of yam badnavirus sequences. Phylogeny and pairwise sequence comparison of 121 yam partial reverse transcriptase sequences provided strong support for the identification of 12 yam badnavirus species, of which ten have not been previously named. Virus prevalence data were obtained, and they support the presence of EPRVs in D. rotundata, but not in D. praehensilis, D. abyssinica, D. alata or D. trifida. Five yam badnavirus species characterised by a wide host range seem to be of African origin. Seven other yam badnavirus species with a limited host range are probably of Asian-Pacific origin. Recombination under natural circumstances appears to be rare. Average values of nucleotide intra-species genetic distances are comparable to data obtained for other RNA and DNA virus families. The dispersion scenarios proposed here, combined with the fact that host-switching events appear common for some yam badnaviruses, suggest that the risks linked to introduction via international plant material exchanges are high.

First Report of Pythium intermedium Causing Root Rot on Rosa canina Rootstock in France

Old cultivars of roses (Rosa spp.) established on Rosa canina as rootstock are grown in field collections in the repository at Gaillard in eastern France, close to the Swiss border. During June 2005 and July 2006, several rose plants in full vegetation were severely wilted, leading ultimately to plant death. Necrotic lesions were present on the roots, and marginal tissue was excised and incubated in the dark at 20°C on PARP V8 agar plates (1). Similar isolates were obtained in both years, which were inoculated within 4 days on V8 agar medium and incubated at 25°C. The pathogen colonies grew approximately 30 mm daily on V8 agar. Colonies on corn meal agar (CMA) (1) were submerged, with or without a vague radiate pattern on potato carrot agar. Main hyphae were as much as 7 μm wide. Sporangia and zoospores were not produced. Hyphal swellings as much as 25 μm in diameter were abundant, terminal, and sometimes intercalary, often forming regular, dense chains in basipetal succession at hyphal tips and readily liberated. The morphological characters matched those described for Pythium intermedium (2). DNA sequencing of the ITS rDNA (ITS1, ITS2, and 5.8S rDNA) was generated using primers ITS5 and ITS4 in primary PCR (35 cycles: 96°C for 1 min, 55°C for 1 min, and 72°C for 2 min) and sequencing reactions (1). All isolates yielded identical ITS sequences, which were identical to the ex-type strain of P. intermedium, CBS 266.38 (GenBank Accession No. AY598647). The ITS sequence was deposited as GenBank Accession No. EF078693 (National Center for Biotechnology Information, NCBI, Bethesda, MD). Pathogenicity testing was performed on 3-year-old Rosa canina rootstocks from clonal propagation in 25 cm in diameter and 40 cm deep pots of compost 297 (Ricoter, Aarberg, Switzerland). Five-day-old mycelial plugs of our isolates grown on CMA (1) were inoculated in two pots, and roots were mechanically wounded. Sterile plugs were used on two control plants set aside. All plants were kept for 2 weeks at 20°C in a glasshouse with sufficient watering. Extensive necrotic lesions developed on inoculated roots, and severe wilting and leaves drying out were also observed. The controls showed no symptoms. P. intermedium was reisolated from margins of root lesions, thus fulfilling the postulates of Koch. P. intermedium was originally isolated from dead plant material (2) but is known as a typical soil inhabitant. It also has been isolated from water and living material from numerous plant species, but never from the genus Rosa until now. To our knowledge, this is the first record of P. intermedium on Rosa spp. grafted on Rosa canina in France. References: (1) L. Belbahri et al. FEMS Microbiol Lett 255:209, 2006. (2) A. J. van der Plaats-Niterink. Stud. Mycol. 21:1, 1981.

Multiple origins of cultivated grapevine (Vitis vinifera L. ssp. sativa) based on chloroplast DNA polymorphisms

The domestication of the Eurasian grape (Vitis vinifera ssp. sativa) from its wild ancestor (Vitis vinifera ssp. sylvestris) has long been claimed to have occurred in Transcaucasia where its greatest genetic diversity is found and where very early archaeological evidence, including grape pips and artefacts of a 'wine culture', have been excavated. Whether from Transcaucasia or the nearby Taurus or Zagros Mountains, it is hypothesized that this wine culture spread southwards and eventually westwards around the Mediterranean basin, together with the transplantation of cultivated grape cuttings. However, the existence of morphological differentiation between cultivars from eastern and western ends of the modern distribution of the Eurasian grape suggests the existence of different genetic contribution from local sylvestris populations or multilocal selection and domestication of sylvestris genotypes. To tackle this issue, we analysed chlorotype variation and distribution in 1201 samples of sylvestris and sativa genotypes from the whole area of the species' distribution and studied their genetic relationships. The results suggest the existence of at least two important origins for the cultivated germplasm, one in the Near East and another in the western Mediterranean region, the latter of which gave rise to many of the current Western European cultivars. Indeed, over 70% of the Iberian Peninsula cultivars display chlorotypes that are only compatible with their having derived from western sylvestris populations.

First Report of Downy Mildew on Greenhouse and Landscape Coleus Caused by a Peronospora sp. in Louisiana and New York

In May 2005, two commercial greenhouse flower growers, one in Louisiana (LA) and one in New York (NY), submitted coleus, Solenostemon scutellarioides (L.) Codd, plants for diagnosis after observing stunted growth, inward curling and twisting of leaves, and leaf abscission on multiple cultivars. Downy mildew-like growth was observable with hand lens or a microscope on the abaxial leaf surfaces of affected plants. Irregular necrotic spotting was present on some, but not all, plants on which sporulation was evident. Microscopic examination of LA material led to tentative identification of the pathogen as Peronospora lamii A. Braun (2). The pale brown conidia ranged from 17 to 26 × 15 to 26 μm (average 23 × 19 μm). Conidiophores ranged from 345 to 561 × 9 to 15 μm. No oospores were found. Additional coleus plants with downy mildew were subsequently found in three retail nurseries in LA in early summer. In NY, infected coleus plants were observed in landscapes in Farmington, Rochester, Ithaca, and in two commercial greenhouses between August and October 2005. NY samples sent to the USDA/APHIS in Beltsville, MD were examined, and the fungus was found to have morphology consistent with P. lamii. Two pathogenicity trials were conducted in NY. Conidia were rubbed from an infected coleus leaf onto the leaves of six healthy potted coleus plants of five cultivars and two basil plants that were placed in a shaded plastic tent in the greenhouse where temperatures ranged from 17 to 22°C. A household humidifier was used to supply mist inside the tent for 5 h per day. Six noninoculated plants of each coleus cultivar and two basil plants, placed in the same environment, served as controls. Downy mildew sporulation and some curling and twisting of leaves were observed 14 days after inoculation on all inoculated plants for three of the five cultivars (Florida Rustic Orange, Aurora Peach, and Aurora Mocha). Cvs. Florida Sun Rose and Lava showed no symptoms or signs of downy mildew. An irregularly shaped brown lesion developed on one inoculated basil leaf, and downy mildew sporulation was evident on the abaxial surface 35 days after inoculation. All noninoculated control plants remained disease free. In a second trial, conidia were rinsed from infected coleus leaves and sprayed onto the abaxial leaf surfaces of three coleus cv. Aurora Mocha plants. Three noninoculated plants served as controls and all were placed in a humidity tent. Leaf twisting and downy mildew sporulation were observed 13 days later on all inoculated plants, and control plants showed no sporulation or symptoms. A downy mildew causing disease of greenhouse-grown basil in Europe, originally identified as P. lamii on the basis of morphology, has recently been reported to be taxonomically distinguishable from P. lamii when tested by molecular methods (1). ITS sequences of coleus downy mildew from NY and LA were nearly identical (99% homology) to those of basil downy mildew from Switzerland and Italy (1). To our knowledge, this is the first report of downy mildew occurrence on coleus. References: (1) L. Belbahri et al. Mycol. Res. 109:1276, 2005. (2) S. M. Francis. Peronospora lamii. Descriptions of Pathogenic Fungi and Bacteria. No. 688. CMI, Kew, England, 1981.

A prospective study of circulating mutant KRAS2 in the serum of patients with colorectal neoplasia: strong prognostic indicator in postoperative follow up

BACKGROUND AND AIMS

Mutant tumour derived DNA has been detected in the sera of colorectal cancer patients. We investigated if mutant serum KRAS2 was detectable preoperatively in a large group of patients with colorectal neoplasia. A prospective study of 94 patients who underwent putative curative resection for colorectal carcinoma (CRC) was performed to ascertain if serum mutant KRAS2 could be used postoperatively as a disease marker.

METHODS

Preoperative sera from 78 patients were analysed (group A). Sera from 94 patients were obtained three monthly for up to three years during the postoperative period (group B). Codon 12 and 13 KRAS2 mutations were analysed in matched tumour and serum samples.

RESULTS

In the preoperative group (group A), KRAS2 mutation was found in 41/78 (53%) tumours and in 32/78 (41%) preoperative sera. Of 41 tumour KRAS2 mutation positive cases, 31/41 (76%) had an identical serum mutation detectable. In group B, the postoperative follow up group, 60/94 cases were primary tumour KRAS2 mutation positive. Of these 60, 16/60 (27%) became persistently serum mutant KRAS2 positive postoperatively. Ten of 16 (63%) of these developed a recurrence compared with only 1/44 (2%) patients who remained serum mutant negative (odds ratio 71.7 (95% confidence interval 7.7-663.9; p=0.0000). None of 34 tumour mutation negative cases became serum mutant KRAS2 positive postoperatively, despite recurrence in 9/34 patients. The relative hazard of disease recurrence in postoperative serum mutant KRAS2 positive patients was 6.37 (2.26-18.0; p=0.000).

CONCLUSIONS

Serum mutant KRAS2 can be detected preoperatively in all stages of colorectal neoplasia. Postoperatively, serum mutant KRAS2 is a strong predictor of disease recurrence, stronger even than Dukes' stage of disease, and thus shows potential for use in clinical practice as a marker of preclinical disease recurrence.

[Epidemiology of childhood asthma in the department of Calvados]

A survey was conducted in 1707 sixth grade school children in the Calvados department of France. A self-administered questionnaire was filled out by the children in the presence of a school nurse. The cumulative prevalence of asthma was 14.9%. There was no significant difference between children living in urban or rural areas. There was however a significant difference by sex: 18% of the boys had asthma and 11% of the girls. The cumulative prevalence of wheezing was 25.4% (current prevalence 12.9%). The current prevalence of dry nocturnal cough, respiratory infections excluded, was 33.3%; that of exercise-induced asthma, 27%. Severity was evaluated on the basis of the number of wheezing episodes since the beginning of the school year (> 3 episodes: 4.5%), the number of awakenings at night per week (several per week: 2.2%), and aggravations severe enough to bother speech (4.3%). The rate of missed school days was 18.5% and that of asthma-related hospitalization 1.8%. One asthmatic child out of 4 had undergone pulmonary function tests and 1 out of 2 had a specific treatment for asthma. The high prevalence of childhood asthma in Calvados, with high morbidity, a significant number of missed school days, the exceptional nature of satisfactory pulmonary function testing, and the inconsistency of specific treatments, emphasizes the need for educational programs for parents and their family and improved physician training.

K-ras mutations are found in DNA extracted from the plasma of patients with colorectal cancer

BACKGROUND & AIMS

Circulating DNA can be isolated from the plasma of healthy subjects and from patients with cancer. The aim of this study was to detect K-ras mutations in DNA extracted from the plasma of patients with colorectal cancer.

METHODS

Tumor and plasma DNA were extracted from 14 patients with colorectal cancer (stages A-D), and K-ras alterations were detected using a polymerase chain reaction assay that uses sequence-specific primers to amplify mutant DNA. These results were confirmed with another polymerase chain reaction assay that creates an enzyme restriction site in the absence of a K-ras mutation followed by direct sequencing and additional cloning techniques.

RESULTS

Seven patients (50%) had a codon 12 K-ras mutation within their primary tumor, and identical mutations were found in the plasma DNA of 6 patients (86%). Mutant DNA was not detected in the plasma specimens of 7 patients whose tumors tested negative for K-ras alterations or in healthy control subjects. Similar results were obtained using all three molecular biological techniques.

CONCLUSIONS

K-ras abnormalities can be detected in circulating DNA extracted from the plasma specimens of patients with colorectal cancer. If these results are confirmed in larger studies, genetic analysis of plasma DNA may have clinical applications in the future.

[Transformation of NIH/3T3 cells and SW 480 cells displaying K-ras mutation]

The spontaneous release of a glyconucleoprotein complex in the supernatant of eukaryote cell cultures is a general phenomenon independent of cell lysis. The DNA recovered from this glyconucleoprotein material contains most part of the genome. The SW 480 cell line, originating from a human colon carcinoma, presents a point mutation of the K-ras gene on both alleles. These cells in culture release the mutated K-ras gene. When crude SW 480 cell supernatant is given, without any other adjonction, to NIH/3T3 mouse cells, transformed foci appear as numerous as those occurring after a transfection provoked by a cloned E.J. ras gene administered as a calcium precipitate. The presence of a mutated ras gene in the transfected foci of the 3T3 cells has been checked by hybridization, after PCR, with an oligonucleotide probe specific to the mutation. This result was confirmed by sequencing the PCR product.

Prognosis of rectal cancer in France

We studied changes in the prognosis of cancer of the rectum (excluding the rectosigmoid junction) from 1978 to 1986 in the French department of Calvados on the basis of the 616 cases in the cancer registry. Taken as whole, survival has improved slightly with time (P < 0.01), but the improvement is only significant for men (P < 0.02), patients under 70 years (P < 0.01) and patients living in urban areas (P < 0.05). With regard to tumour characteristics, the improvement was significant only for patients with Dukes' stage C tumours at surgery (P < 0.02). To determine the reasons for the improvement in survival, the year of diagnosis and all other prognostic factors were studied in a multivariate model. Diagnostic conditions such as age and tumour stage did not vary from 1978 to 1986; in contrast, the rates of tumour resection and adjuvant radiation therapy increased, possibly explaining at least part of the improvement, particularly for patients with Dukes' stage C tumours.

Uterine height and umbilical perimeter curves in twin pregnancies

From previous research, which gave standard curves for the evolution of uterine height and umbilical perimeter according to gestational age in the case of single pregnancies, the authors propose curves which show the variations of these two parameters in twin pregnancies. The observed differences are sufficient to allow a diagnosis of twin pregnancy as soon as the 18th week of amenorrhea. This observation is interesting because, until now, a systematic early B-scan examination has not been performed as a rule.

Intrauterine growth charts for twin fetuses

In addition to centile curves for birth weight and height of single infants, the authors offer similar biometric references for twins derived from a large French data base. The aim of the work is to assist in discovering small-for-date twins. In the actual prenatal environment, the curves show a decrease in the evolution of these growth parameters in comparison with the single pregnancy standards as early as the 30th week of pregnancy.

[Uterine height and umbilical circumference - an index of uterine development]

The importance of clinical follow-up of the growth in size of the uterus in the screening of intrauterine underdevelopment of the fetus and also other ovulatory anomalies has been stressed by the authors, and the acceptable standards for uterine heighth and umbilical circumference at the various stages of pregnancy have been assessed. Reference curves establishing the limits that correspond to 10th and 90th percentiles have been determined. An individual diagram that would permit to visualize successive measurements in any pregnant woman has been proposed. The authors have recommanded the use of an index of uterine development the abnormal values of which should be included in the evaluation of risk.