Hemoglobin Denver, a cause of desaturated pulse oximetry. A pediatric case report

Hemoglobinopathies are genetic disorders that affect the hemoglobin (Hb) molecule. Mutations in the alpha or beta chains altering the Hb tetramer may modify the molecule's oxygen-binding capacity. Hemoglobinopathies with low oxygen affinity may occur with cyanosis and an altered pulse oximetry reading, leading to unnecessary and sometimes invasive tests to rule out cardiovascular and respiratory conditions. In the case report described here, we present an asymptomatic pediatric patient who consulted for desaturated pulse oximetry. Her initial laboratory tests showed normocytic, normochromic anemia. Venous blood gas samples showed an elevated p50. After using extensive diagnostic tools, a variant of Hb with low oxygen affinity was diagnosed: Hb Denver.

Six novel variants in the PKLR gene associated with pyruvate kinase deficiency in Argentinian patients

BACKGROUND

Pyruvate kinase deficiency (PKD) is a rare recessive congenital hemolytic anemia caused by mutations in the PKLR gene. The disease shows a marked variability in clinical expression. We studied the molecular features of nine unrelated Argentinian patients with congenital hemolytic anemia associated with erythrocyte pyruvate kinase deficiency.

DESIGN AND METHODS

Routine hematologic investigations were performed to rule out other causes of chronic hemolytic anemia. Sanger sequencing and in-sílico analysis were carried out to identify and characterize the genetics variants.

RESULTS

Six different novel missense variants were detected among the 18 studied alleles: c.661 G > C (Asp221His), c.956 G > T (Gly319Val), c.1595 G > C (Arg532Pro), c.347 G > A (Arg116Gln), c.1232 G > T (Gly411Val), c.1021G > A (Gly341Ser). Structural implications of amino-acid substitutions were correlated with the clinical phenotypes seen in the probands.

CONCLUSIONS

This is the first comprehensive report on molecular characterization of pyruvate kinase deficiency in Argentina and the second from South America that would contribute to our knowledge on the distribution and frequency of PKLR variants in our population but also offer new insights into the interpretation of the effect of PKLR variants and phenotype.

Understanding clinical practice and survival outcomes in patients with unresectable stage III non-small-cell lung cancer in a single centre in Quebec

Methods

A retrospective cohort study considered patients 18 or more years of age diagnosed between January 2007 and May 2018 with unresectable stage iii non-small-cell lung cancer (nsclc) who received combined chemoradiation (crt). Survival was analyzed using the Kaplan-Meier method to determine median overall (os) and progression-free survival (pfs) and the associated 95% confidence intervals (cis). Cox regression analysis was performed to identify factors prognostic for survival, including age, sex, smoking status, Eastern Cooperative Oncology Group performance status (ecog ps), histology, treatment type, tumour size, and nodal status.

Results

Of 226 patients diagnosed with unresectable stage iii disease, 134 (59%) received combined crt. Mean age was 63 years; most patients were white, were current smokers, had an ecog ps of 0 or 1, and had nonsquamous histology. Median pfs was 7.03 months (95% ci: 5.6 months to 8.5 months), and os for the cohort was 18.7 months (95% ci: 12.4 months to 24.8 months). Of those patients, 78% would have been eligible for durvalumab consolidation therapy. Univariate analysis demonstrated a significant os benefit (p = 0.010) for concurrent crt (ccrt) compared with sequential crt (scrt). Disease-specific survival remained significantly better in the ccrt group (p = 0.004). No difference in pfs was found between the ccrt and scrt groups. In addition, tumour size and nodal involvement were significant discriminating factors for survival (p < 0.05). In this patient cohort, 64% of patients progressed and received subsequent therapy. Based on multivariate analysis, tumour size and nodal station were the only factors predictive of survival in patients with unresectable stage iii nsclc treated with crt.

Conclusions

Combined crt has been the standard treatment for unresectable stage iii nsclc. In our study, a trend of better survival was seen for ccrt compared with scrt. Factors predictive of survival in patients with stage iii disease treated with crt were tumour size and nodal station. Most patients with stage iii disease would potentially be eligible for durvalumab maintenance therapy based on the eligibility criteria from the pacific trial. The use and effectiveness of novel treatments will have to be further studied in our real-world patient population and similar populations elsewhere.

Phenotypic and genotypic characterization of glucose-6-phosphate dehydrogenase deficiency in Argentina. Retrospective and descriptive study

Glucose-6-phosphate dehydrogenase deficiency is an erythrocyte enzyme disorder caused by mutations in the G6PD gene, which has an X-linked inheritance. Here we analyze the clinical and laboratory characteristics of 24 subjects with G6PD deficiency over 25 years. Their median age at diagnosis was 10.2 years (range: 0.6-56.4). No symptoms were observed in 54.2 % of patients, whereas 25 % had chronic non-spherocytic hemolytic anemia; 12.5 %, neonatal jaundice and postinfectious hemolytic anemia; and 8.3 %, acute hemolytic anemia after ingestion of fava beans. The 24 studied patients had variants that had been previously described in the bibliography. The clinical characteristics observed here were consistent with the variants found. A total of 21 women from the maternal line of affected subjects were identified as deficiency carriers using molecular biology techniques, so they received the corresponding genetic counseling.

[Hereditary xerocytosis. Presentation of two pediatric cases]

Hereditary xerocytosis is a rare disorder caused by defects of red blood cell permeability that are characterized by hemolytic anemia of variable degree and iron overload. Diagnosis is usually late and confused with other hemolytic anemias, which can lead to procedural indications, such as splenectomy, contraindicated in these patients. We report the clinical, haematological, and molecular characteristics of two patients from two unrelated families affected by hereditary xerocytosis. Both patients had dehydrated erythrocytes with a high concentration of mean corpuscular hemoglobin, non-pathognomonic smears, markers of hemolysis and a resistant osmotic fragility curve. The diagnosis was confirmed by the sequencing of the PIEZO gene. We emphasize the importance of recognizing the cause of hemolytic anemia to give an accurate therapeutic approach and give adequate genetic counseling.

Cytology cell blocks are suitable for immunohistochemical testing for PD-L1 in lung cancer

Background

PD-L1 immunohistochemistry (IHC) testing is usually carried out on tissue blocks from core needle biopsy or surgical resections. In this study, we assessed the feasibility of using cytology cell blocks for PD-L1 IHC assay.

Methods

A total of 1419 consecutive cases of non-small-cell lung cancer (NSCLC), including 371 cytology cell blocks, 809 small biopsies, and 239 surgical specimens, were included in the study. The cytology cell blocks were prepared with formalin only, methanol/alcohol only or both. PD-L1 expression was examined by staining with Dako PD-L1 IHC 22C3 pharmDx kit. A Tumor Proportion Score (TPS) was categorized as <1%, 1%-49% and ≥50% tumor cells. A total of 100 viable tumor cells were required for adequacy.

Results

Of the cytology cell blocks, 92% of the specimens had an adequate number of tumor cells, not significantly different from small biopsies. The rate of TPS ≥50% differed between sample types and was observed in 42% of cytology cell blocks versus 36% of small biopsies (P = 0.04), and 29% of surgical resections (P = 0.001). The fixative methods did not affect the immunostaining, with overall PD-L1 high expression (TPS ≥50%) rates of 42% in formalin-fixed specimens versus 40% in specimens with combined fixation by methanol/alcohol and formalin (NS). The PD-L1 high expression rate was not associated with EGFR, ALK or KRAS molecular alterations. Higher stage (IV) was associated with higher PD-L1 TPS (P= 0.001).

Conclusion

Our results show that when the TPS ≥50% is used as the end point, PD-L1 IHC performs well with cytology cell blocks. Cell blocks should be considered as a valuable resource for PD-L1 testing in advanced NSCLC. The clinical significance of higher PD-L1 IHC scores in cytology specimens needs to be evaluated prospectively.

The metastatic site does not influence PD-L1 expression in advanced non-small cell lung carcinoma

INTRODUCTION

PD-L1 expression by immunohistochemistry (IHC) testing with Tumor Proportion Score (TPS) ≥50% and ≥1% is required to be eligible for first- and second-line Pembrolizumab treatment for metastatic non-small cell lung cancer (NSCLC) respectively. Stage IV NSCLC often presents with metastasis to multiple distant sites which are easily accessible for biopsy. Knowing whether PD-L1 IHC TPS can be indifferently measured from different metastatic site is therefore an important clinical question. In this study, we evaluated PD-L1 expression in NSCLC from varied distant metastatic sites.

METHODS

A total of 580 NSCLC specimens of distant metastases were retrieved for study, including 35 paired samples from two different metastatic sites. The metastatic sites included brain, bone, remote lymph nodes, serous membranes (pleura, pericardium and peritoneum), extra-thoracic solid organs and skin/soft tissues. The samples were cytology cell blocks, small biopsies or surgical resections. IHC was performed using Dako PD-L1 IHC 22C3 pharmDx. A total of 100 viable tumor cells was required for adequacy. TPS ≥ 50% and 1-49% were defined as high and low PD-L1 expression respectively.

RESULTS

PD-L1 TPS scores were not significantly different across a range of distant metastatic sites nor between metastases in paired samples.

CONCLUSION

Our results suggest that the PD-L1 TPS scoring is similar across different metastatic sites and any site biopsied will yield necessary information for guiding clinical management.

Does the presence of emphysema increase the risk of radiation pneumonitis in lung cancer patients?

Introduction

Radiotherapy (rt) plays an important role in the treatment of lung cancer. One of the most common comorbidities in patients with lung cancer is pulmonary emphysema. The literature offers conflicting data about whether emphysema increases the occurrence and severity of radiation pneumonitis (rp). As a result, whether high doses of rt (with curative intent) should be avoided in patients with emphysema is still unclear.

Objective

We measured the documented incidence of rp in patients with and without emphysema who received curative radiation treatment.

Methods

This retrospective cohort study considered patients in the lung cancer clinical database of the Peter Brojde Lung Cancer Centre. Data from the database has been used previously for research studies, including a recent publication about emphysema grading, based on the percentage of lung occupied by emphysema on computed tomography (ct) imaging.

Results

Using previously published methods, chest ct imaging for 498 patients with lung cancer was scored for the presence of emphysema. The analysis considered 114 patients who received at least 30 Gy radiation. Of those 114 patients, 64 (56%) had emphysema, with approximately 23% having severe or very severe disease. The incidence of rp was 34.4% in patients with emphysema (n = 22) and 32.0% in patients with no emphysema (n = 16, p = 0.48). No difference in the incidence of rp was evident between patients with various grades of emphysema (p = 0.96). Similarly, no difference in the incidence of rp was evident between the two treatment protocols-that is, definitive rt 17 (37%) and combined chemotherapy-rt 21 (31%, p = 0.5).

Conclusions

In our cohort, the presence of emphysema on chest ct imaging was not associated with an increased risk of rp. That finding suggests that patients with lung cancer and emphysema should be offered rt when clinically indicated. However, further prospective studies will be needed for confirmation.

Lung cancer care trajectory at a Canadian centre: an evaluation of how wait times affect clinical outcomes

BACKGROUND

Lung cancer continues to be one of the most common cancers in Canada, with approximately 28,400 new cases diagnosed each year. Although timely care can contribute substantially to quality of life for patients, it remains unclear whether it also improves patient outcomes. In this work, we used a set of quality indicators that aim to describe the quality of care in lung cancer patients. We assessed adherence with existing guidelines for timeliness of lung cancer care and concordance with existing standards of treatment, and we examined the association between timeliness of care and lung cancer survival.

METHODS

Patients with lung cancer diagnosed between 2010 and 2015 were identified from the Pulmonary Division Lung Cancer Registry at our centre.

RESULTS

We demonstrated that the interdisciplinary pulmonary oncology service successfully treated most of its patients within the recommended wait times. However, there is still work to be done to decrease variation in wait time. Our results demonstrate a significant association between wait time and survival, supporting the need for clinicians to optimize the patient care trajectory.

INTERPRETATION

It would be helpful for Canadian clinicians treating patients with lung cancer to have wait time guidelines for all treatment modalities, together with standard definitions for all time intervals. Any reductions in wait times should be balanced against the need for thorough investigation before initiating treatment. We believe that our unique model of care leads to an acceleration of diagnostic steps. Avoiding any delay associated with referral to a medical oncologist for treatment could be an acceptable strategy with respect to reducing wait time.

Two novel DNA variants associated with glucose-6-phosphate dehydrogenase deficiency found in Argentine pediatric patients

OBJECTIVE

The enzyme glucose-6-phosphate dehydrogenase (G6PD) catalyses the first step in the pentose phosphate pathway, producing nicotinamide adenine dinucleotide phosphate (NADPH). NADPH plays a crucial role in preventing oxidative damage to proteins and other molecules in cells, mostly red blood cells. G6PD deficiency has an x-linked pattern of inheritance in which hemizygous males are deficient, while females may or may not be deficient depending on the number of affected alleles. We report two novel DNA variants in the G6PD gene detected in two male probands with chronic nonspherocytic hemolytic anemia (CNSHA), who were referred for hematological evaluation.

METHOD

Probands and their relatives underwent clinical, biochemical, and molecular assessment.

RESULTS

Two novel DNA variants, c.995C>T and c.1226C>A, were found in this study. At the protein level, they produce the substitution of Ser332Phe and Pro409Gln, respectively. These DNA variants were analyzed in the female relatives of probands for genetic counseling.

CONCLUSIONS

The novel DNA variants were classified as class I based on the clinical, biochemical, and molecular evaluations performed.

[Beta thalassemia intermedia: clinical characteristics and molecular analysis. Case series]

Beta thalassemia intermedia is a quantitative haemoglobinopathy covering a broad clinical spectrum, that results from the presence of one or two HBB gene mutations associated with secondary and/or tertiary genetic modifiers. We analyze the clinical and laboratory features of 29 patients with beta thalassemia intermedia, assessed over a period of 23 years. Median age was 10.8 years (range: 0.34-60.4). Hypochromic microcytic anemia was seen in 100% of the patients, while only 17.2% had splenomegaly and occasional transfusion requirement. The molecular analysis of patients detected: 3 with two HBB affected genes; 2 with one HBB affected gene and alpha quadruplicate/triplicate genes; 23 with one HBB affected gene and alpha triplicate genes and 1 with two HBB affected genes and polymorphisms of gamma genes. The adequate identification of these patients enables us to give appropriate genetic counseling and implementation of regular clinical follow up.

[Hemoglobin Woodville associated with double point mutation in the gene of glucose-6-phosphate dehydrogenase]

The co-inheritance of erythrocyte defects, hemoglobinopathies, enzymopathies, and membranopathies is not an unusual event. For the diagnosis, a laboratory strategy, including screening and confirmatory tests, additional to molecular characterization, was designed. As the result of this approach, a 24-year-old man carrying a hemoglobinopathy (Hemoglobin Woodville) and an enzymopathy (glucose-6-phosphate dehydrogenase deficiency) was identified. In the heterozygous state hemoglobin Woodville, is asymptomatic, and homozygous or double heterozygous individuals have not been reported thus far. On the other hand, previously described double point mutation in the gene for glucose-6-phosphate dehydrogenase c. [202G>A; 376A>G], p. [Val 68Met; Asn126Asp], causes hemolysis of varying severity after food or drug intake or infections. This case highlights the importance of the methodology carried out for the diagnosis, treatment, and proper genetic counseling.

A new β(0) frameshift mutation, HBB: c.44delT (p.Leu14ArgfsX5), identified in an Argentinean family associated with secondary genetic modifiers of β-thalassemia

β-Thalassemia intermedia (β-TI) patients present with a wide spectrum of phenotypes depending on the presence of primary, secondary, and tertiary genetic modifiers which modulate, by different mechanisms, the degree of imbalance between α and β chains. Here we describe a new β(0) frameshift mutation, HBB: c.44delT (p.Leu14ArgfsX5), identified in four members of a family, associated with secondary genetic modifiers in three of them. The different genotype present in this family was suspected after hematological analysis and thorough observation of blood smears highlighting their importance in the identification of β-TI patients among members of the same family.

Palatability and stability of shortbread made with low saturated fat content

High consumption of saturated fatty acids (SFA) is associated with increased risk of cardiovascular disease and the European Food Safety Agency has called for lower SFA intake. This study assessed the formulation of low SFA shortbreads by replacing 60% and 70% of the butter content with high oleic sunflower oil and water. The quality of the low SFA shortbreads was evaluated through acidity, peroxide value, moisture, ash content, water activity, pH, protein, fat content, and fatty acid profiles. A sensory evaluation was performed to ascertain the effect on flavor. Stability of the new formulations was assessed by conducting accelerated shelf-life studies. The high oleic sunflower oil replacement of butter at levels of 60% and 70% decreased the final SFA content by 52% and 61%, respectively. On the other hand, monounsaturated fat content increased 55% on average while polyunsaturated fat content increased by 40%. Furthermore the new formulations possess quality parameters similar to those of traditional shortbreads (TSs). The study of the shelf life of the products showed that there are no significant variations in peroxide values, malondialdehyde content, or fatty acid profiles in biscuits over time, confirming their high stability. The quantitative descriptive analysis showed that the TS and low SFA shortbreads have similar sensory profiles, and the consumer tests indicated that the low SFA shortbreads were well liked.

The potential role for acupuncture in treating symptoms in patients with lung cancer: an observational longitudinal study

BACKGROUND

Most lung cancer patients experience multiple symptoms related either to the disease or its treatment. The commonly reported symptoms are pain, depression, anxiety, nausea, and poor well-being. The aim of the present study was to evaluate the effect of acupuncture as a potential treatment modality in symptomatic lung cancer patients.

METHODS

This prospective observational study enrolled 33 lung cancer patients from the Peter Brojde Lung Cancer Centre between August 2010 and May 2012. All patients received 45-minute sessions of acupuncture, 1-2 times weekly for a minimum of 4 sessions. Symptom severity was assessed using the Edmonton Symptom Assessment System (esas) before and after completion of acupuncture.

RESULTS

The study cohort included 30 patients with non-small- cell lung cancer and 3 with small-cell lung cancer. Mean age was 62 years (range: 36-88 years); 17 of the patients were women. Most of the patients had advanced-stage cancer (73%) and good performance status (Eastern Cooperative Oncology Group 0-1: 88%). Of these patients, 67% received anticancer treatment (chemotherapy or radiotherapy, or both) with acupuncture. Of the remaining 10 patients, 8 received acupuncture after a complete surgical resection of their tumour, and because of their advanced age, 2 received acupuncture and best supportive care. The median number of acupuncture sessions was 7 (interquartile range: 4-13 sessions). Statistically significant improvements in pain, appetite, nausea, nervousness, and well-being were observed. A clinically important improvement (2 points on the esas) was reported by 61% of patients for pain and by 33% for well-being. A significant positive correlation between improved well-being and the number of acupuncture sessions was observed. This correlation remained significant even after controlling for treatment and narcotic use. Receiver operating characteristic analysis demonstrated that a minimum of 6 acupuncture sessions are required for a 70% chance of a clinically important improvement in well-being.

CONCLUSIONS

The present study is the first to demonstrate that acupuncture may be an effective approach for improving symptoms-in particular, pain and well-being-in lung cancer patients. Acupuncture is a safe and minimally invasive procedure, and it is potentially useful even in patients undergoing anticancer treatment.

The predictive value of pre-treatment inflammatory markers in advanced non-small-cell lung cancer

BACKGROUND

Accurate prediction of outcome in advanced non-small-cell lung cancer (NSCLC) remains challenging. Even within the same stage and treatment group, survival and response to treatment vary. We set out to determine the predictive value of inflammatory markers C-reactive protein (CRP) and white blood cells (WBCS) in patients with advanced NSCLC.

PATIENTS AND METHODS

Patients were assigned a prognostic index (PI): 0 for crp 10 mg/L or less and WBCS 11x10⁹/L or less, 1 if one of the two markers was elevated, and 2 if both markers were elevated. We then used chest computed tomography (CT) imaging to evaluate response after 2 cycles of chemotherapy treatment.

RESULTS

Of 134 patients, 46 had a PI of 0; 60, a PI of 1; and 28, a PI of 2. Disease progressed in 41 patients. Progression was significantly more frequent among patients with a PI of 2 (p = 0.008). Median survival was 20.0 months for the PI 0 group, 10.4 months for the PI 1 group, and 7.9 months for the PI 2 group (p < 0.001). The PI was the only significant prognostic factor for survival even after adjustment for performance status, smoking, and weight loss (hazard ratio: 1.57; 95% confidence interval: 1.2 to 2.14; p = 0.004).

CONCLUSIONS

Inflammatory state correlates significantly with both chemotherapy response and survival in stage IV NSCLC. The PI may provide additional guidance for therapeutic decision-making.

Metformin, estrogen replacement therapy and gonadotropin inhibition fail to improve insulin sensitivity in a girl with aromatase deficiency

BACKGROUND

Insulin resistance (IR), abnormal lipid profile, and other features of the metabolic syndrome have been described in CYP19 gene knockout mice and in aromatase-deficient adult men but not in prepubertal affected girls.

AIMS

To study insulin sensitivity, as well as the effects of estrogen, metformin and GnRHa treatment on glucose homeostasis, in an aromatase-deficient girl.

METHODS

Clinical, metabolic and hormonal follow-up data, from 8 to 12 years of age, is presented.

RESULTS

At 9 years of age, IR (HOMA 5.6) and glucose intolerance was detected, along with high serum testosterone (2.28 nmol/l), androstenedione (4.92 nmol/l) and FSH (13.4 mIU/ml) levels. Estrogen replacement was ineffective to suppress gonadotropin and androgen levels, as well as IR. Under metformin therapy, she developed type 2 diabetes and acanthosis nigricans. GnRHa administration for 1 year resulted in marked decreases in gonadotropin and serum androgens, but severe IR persisted.

CONCLUSION

Postnatal estrogen replacement and a marked decrease of endogenous androgens failed to improve IR and glucose tolerance. We propose that, in females, the increment of androgens and/or lack of estrogens during fetal life might alter the mechanism of fetal programming of insulin sensitivity.

Anatomic response correlation with biological response

8092

Background: Chronic systemic inflammation is a well recognized strong adverse prognostic factor in advanced NSCLC. We have previously identified that in stage IIIB/IV NSCLC the presence of elevated C-reactive protein is associated with early progression of the disease and reduction in median survival. Little is known, however, about CRP behavior over time and its correlation with response to chemotherapy and survival. Methods: Newly diagnosed NSCLC with IIIB/IV disease had CRP measured prior to 1st treatment and after 2 cycles of chemotherapy between February 2005 and September 2008. For each measure CRP level was categorized as < 10mg/L or ≥10mg/L. Response was evaluated by chest CT following two cycles of CTX and rated as progression (PD) or freedom from progression (FFP). We investigated the association between change in CRP and response to 2 cycles of CTX, as well as survival. Results: 143 pts were enrolled. Of those, 62 patients had a CRP level <10mg/L and 81 patients ≥10mg/L at the time of diagnosis. After 2 cycles 70% and 72% of pts in each category remained in the same category and 30% and 28% of patients changed category: in 24/81 pts CRP decreased below 10mg/L and in 17/62 pts CRP increased above 10mg/L. Thus, after two cycles 69 pts had CRP <10mg/L and 74 pts ≥10mg/L. The rate of progression after 2 cycles was significantly lower among pts with CRP <10mg/L after 2 cycles of chemo ( Table ). Median survival was 19 (16–22) mo for those with CRP <10mg/L and 9.3 (7.1–11.4) mo for those with CRP ≥10mg/L after 2 cycles (P<0.001). The hazard increased by 66% (HR 1.7) for those pts with CRP increased above cut-off point of 10 mg/L and decreased by 60% (HR 1.6) for pts whose CRP decreased below cutoff point. Conclusions: The presence of an inflammatory state expressed by high levels of CRP either prior to treatment or following 2 cycles of chemotherapy correlates significantly with both first-line chemotherapy response and survival. Normalization of CRP might improve the prognosis of patients in terms of survival and response to chemotherapy.

[Table: see text]

No significant financial relationships to disclose.

Cytoplasmic beta-catenin is lacking in a subset of melanoma-associated naevi, but is detectable in naevus-associated melanomas: potential implications for melanoma tumorigenesis?

BACKGROUND

An excess of intracellular beta-catenin protein is triggered by various genetic alterations in melanoma cell lines, and has been suggested to play a role in melanoma tumorigenesis.

OBJECTIVES

To investigate the role played in vivo by beta-catenin in melanoma tumorigenesis, we compared the cytoplasmic detection of beta-catenin in benign melanocytic cells vs. malignant melanoma cells presumably generated from these benign melanocytic cells. For this purpose, melanocytic naevi occurring in association with melanoma, which were suggested to be melanoma precursors, were compared with their associated melanoma for beta-catenin cytoplasmic immunoreactivity.

METHODS

Fifty-seven consecutive cases of primary cutaneous melanoma were considered, and 15 of them were found to be associated with a melanocytic naevus portion. The naevus portion showed features of acquired melanocytic naevus (total 12 cases: five dysplastic, seven intradermal) or congenital growth pattern naevus (total three cases: one superficial, two deep). All specimens were immunohistochemically investigated for beta-catenin.

RESULTS

Virtually all primary cutaneous melanomas, including those associated with a naevus portion, showed cytoplasmic beta-catenin positivity. However, the intradermal naevus portion was consistently cytoplasmic beta-catenin negative, while both the dysplastic and the congenital naevus portions were cytoplasmic beta-catenin positive.

CONCLUSIONS

Beta-catenin excess may play a role in melanoma tumorigenesis, because beta-catenin cytoplasmic reactivity was found in primary cutaneous melanoma but not in its associated intradermal naevus precursor. As, however, beta-catenin cytoplasmic reactivity was detected not only in primary cutaneous melanoma but also in its associated dysplastic/congenital naevus precursors, beta-catenin stabilization alone is not sufficient to play a decisive role for melanoma onset.

Clinicopathologic features and prognostic implications of epidermal growth factor receptor (EGFR) gene mutations detected by denaturing high-performance liquid chromatography (dHPLC) in non-small cell lung cancer (NSCLC)

7594

Background: Somatic mutations of the EGFR gene predict sensitivity to erlotinib and gefitinib and confer a favorable prognosis in patients (pts) with NSCLC. We have recently shown that dHPLC is an efficient and more sensitive method for mutation screening compared with DNA sequencing. The goal of this study was to describe the relationship between EGFR status (mutation status and type) and clinicopathologic factors. Methods: Tumor samples were analysed for EGFR exon 19 deletions and exon 21 L858R point mutations. DNA was extracted from paraffin-embedded tumor specimens and genotyped using dHPLC. The results were correlated with gender, smoking status, pathologic subtype, disease stage, and overall survival. Results: 215 NSCLC pts were genotyped. Mutations were present in 25% of cases (54 of 215). Among pts with mutations, 70% (38 of 54) had an exon 19 mutation whereas 30% had EGFR L858R. EGFR mutations were more common in women (31% vs 14%; p=0.008), in nonsmokers than ever-smokers (54% vs 17%; p<0.001), in adenocarcinomas/BAC than with other NSCLC histologies (31% vs 11%; p=0.004) and more frequently detected in advanced-stage than in early-stage disease (36% vs 15%; p=0.001). Median survival times of pts with stage IIIB-IV disease with and without EGFR mutations were 20 and 14 months, respectively. Those with exon 19 deletion mutations had a longer median survival than pts with L858R point mutations. Data describing the impact of tyrosine kinase inhibitor therapy on survival outcomes are pending and will be presented. Conclusion: dHPLC is a reliable tool for EGFR mutation detection. Mutations were preferentially observed in women, nonsmokers, adenocarcinomas/BAC and in patients with advanced disease. Pts with mutations experienced improved survival and those harboring deletions fared better than those with point mutations. These observations warrant confirmation in large prospective trials and exploration of the biological mechanisms of the differences between mutation types.

No significant financial relationships to disclose.

Effect of chemotherapy on exercise capacity in patients with advanced non-small cell lung cancer (NSCLC)

9115

Background: The 6 minute walking distance (6MW) is commonly used to evaluate cardiopulmonary exercise capacity in a variety of patient (pt) populations. Although the 6MW test improved in advanced breast cancer pts who responded to 2 cycles of chemotherapy, (Nieman et al 1995), little is known about exercise capacity of pts with inoperable lung cancer. We prospectively evaluated 6MW in advanced NSCLC pts at diagnosis and following 2 cycles of chemotherapy (CT). Methods: 6MW was performed twice pre (one practice test) and once post 2 cycles of CT. Intent to treat (ITT) analysis was performed in pts who did not complete the last walk. A score of 0 was assigned to those who died and the last observation was carried forward for those with missing data. Results: 59 pts were enrolled though 6 pts withdrew following the practice test due to clinical deterioration (2 pts), pulmonary embolism (1pt), leg pain following the practice walk (1 pt) and withdrawal of consent (2 pts). The mean age of the remaining 53 pts was 61 ±11, PS was 0–1 in 46 (87%) and 2 in 7 (13%) of pts. 8 pts (15%) were stage 3A/3B and 45 (85%) were stage 3B /4 NSCLC. 45 (85%) pts received platinum-based doublets, whereas 8 (15%) had monotherapy. 39 pts completed the study and 14 pts did not complete the second evaluation (4 died, 8 withdrew due to worsening symptoms and 2 were lost for follow-up). The practice 6MW of the 20 pts who dropped out was 361±99 m compared to 448± 93m for the 39 who completed the study (p=0.002). The 6MW decreased from 461±108 m (range 247–748) to 431±98 (range 431–630) in the 39 pts who completed the study (p=0.02) and from 444±106 to 395±107 in the 53 pts using the ITT analysis (p<0.003). There was a clinically significant (>54 m) decrease in 6MW in 11 pts (28%), an increase in 6MW in 2 pts (5%), and no change in 26 (67%) others. The 6MW was higher in men and in pts in stages 3A/B (p<0.05). Conclusions: Exercise capacity, measured by 6MW, declines significantly after two cycles of chemotherapy. This decline may have been underestimated as pts with lower 6MW were more likely to drop out of the study.

No significant financial relationships to disclose.