CT diagnosis of ilioinguinal lymph node metastases in melanoma using radiological characteristics beyond size and asymmetry.

BACKGROUND: Diagnosis of lymph node (LN) metastasis in melanoma with non-invasive methods is challenging. The aim of this study was to evaluate the diagnostic accuracy of six LN characteristics on CT in detecting melanoma-positive ilioinguinal LN metastases, and to determine whether inguinal LN characteristics can predict pelvic LN involvement. METHODS: This was a single-centre retrospective study of patients with melanoma LN metastases at a tertiary cancer centre between 2008 and 2016. Patients who had preoperative contrast-enhanced CT assessment and ilioinguinal LN dissection were included. CT scans containing significant artefacts obscuring the pelvis were excluded. CT scans were reanalysed for six LN characteristics (extracapsular spread (ECS), minimum axis (MA), absence of fatty hilum (FH), asymmetrical cortical nodule (CAN), abnormal contrast enhancement (ACE) and rounded morphology (RM)) and compared with postoperative histopathological findings. RESULTS: A total of 90 patients were included. Median age was 58 (range 23-85) years. Eighty-eight patients (98 per cent) had pathology-positive inguinal disease and, of these, 45 (51 per cent) had concurrent pelvic disease. The most common CT characteristics found in pathology-positive inguinal LNs were MA greater than 10 mm (97 per cent), ACE (80 per cent), ECS (38 per cent) and absence of RM (38 per cent). In multivariable analysis, inguinal LN characteristics on CT indicative of pelvic disease were RM (odds ratio (OR) 3.3, 95 per cent c.i. 1.2 to 8.7) and ECS (OR 4.2, 1.6 to 11.3). Cloquet's node is known to be a poor predictor of pelvic spread. Pelvic LN disease was present in 50 per cent patients, but only 7 per cent had a pathology-positive Cloquet's node. CONCLUSION: Additional CT radiological characteristics, especially ECS and RM, may improve diagnostic accuracy and aid clinical decisions regarding the need for inguinal or ilioinguinal dissection.

Adjuvant therapy following oesophagectomy for adenocarcinoma in patients with a positive resection margin.

BACKGROUND: The role of adjuvant therapy in patients with oesophagogastric adenocarcinoma treated by neoadjuvant chemotherapy is contentious. In UK practice, surgical resection margin status is often used to classify patients for receiving adjuvant treatment. The aim of this study was to assess the survival benefit of adjuvant therapy in patients with positive (R1) resection margins. METHODS: Two prospectively collected UK institutional databases were combined to identify eligible patients. Adjusted Cox regression analyses were used to compare overall and recurrence-free survival according to adjuvant treatment. Recurrence patterns were assessed as a secondary outcome. Propensity score-matched analysis was also performed. RESULTS: Of 616 patients included in the combined database, 242 patients who had an R1 resection were included in the study. Of these, 112 patients (46·3 per cent) received adjuvant chemoradiotherapy, 46 (19·0 per cent) were treated with adjuvant chemotherapy and 84 (34·7 per cent) had no adjuvant treatment. In adjusted analysis, adjuvant chemoradiotherapy improved recurrence-free survival (hazard ratio (HR) 0·59, 95 per cent c.i. 0·38 to 0·94; P = 0·026), with a benefit in terms of both local (HR 0·48, 0·24 to 0·99; P = 0·047) and systemic (HR 0·56, 0·33 to 0·94; P = 0·027) recurrence. In analyses stratified by tumour response to neoadjuvant chemotherapy, non-responders (Mandard tumour regression grade 4-5) treated with adjuvant chemoradiotherapy had an overall survival benefit (HR 0·61, 0·38 to 0·97; P = 0·037). In propensity score-matched analysis, an overall survival benefit (HR 0·62, 0·39 to 0·98; P = 0·042) and recurrence-free survival benefit (HR 0·51, 0·30 to 0·87; P = 0·004) were observed for adjuvant chemoradiotherapy versus no adjuvant treatment. CONCLUSION: Adjuvant therapy may improve overall survival and recurrence-free survival after margin-positive resection. This pattern seems most pronounced with adjuvant chemoradiotherapy in non-responders to neoadjuvant chemotherapy.

ANTECEDENTES: El papel del tratamiento adyuvante en pacientes con adenocarcinoma esofagogástrico tratados con quimioterapia neoadyuvante es polémico. En la práctica del Reino Unido, el estado del margen de resección quirúrgico se utiliza a menudo para identificar a los pacientes que reciben tratamiento adyuvante. El objetivo de este estudio fue evaluar el beneficio en la supervivencia del tratamiento adyuvante en pacientes con márgenes de resección positivos (R1). MÉTODOS: Se combinaron dos bases de datos de instituciones del Reino Unido que recogen información de forma prospectiva para identificar pacientes elegibles. Se utilizaron análisis de regresión de Cox ajustados para comparar la supervivencia global y la supervivencia libre de recidiva según el tratamiento adyuvante. Los patrones de recidiva se evaluaron como resultado secundario. También se realizó un análisis de emparejamiento por puntaje de propensión. RESULTADOS: De 616 pacientes incluidos en la base de datos combinada, se incluyeron en el estudio 242 pacientes con resección R1. De estos pacientes, 112 (46%) recibieron quimiorradioterapia adyuvante, 46 (19%) pacientes fueron tratados con quimioterapia adyuvante y 84 (35%) pacientes no recibieron ningún tratamiento. En el análisis ajustado, la quimiorradioterapia adyuvante mejoró la supervivencia libre de recidiva (cociente de riesgos instantáneos, hazard ratio, HR 0,59, i.c. del 95% 0,38-0,94; P = 0,026) con un beneficio tanto para la recidiva local (HR 0,48, i.c. del 95% 0,24-0,99; P = 0,047) como para la sistémica (HR 0,56, i.c. del 95% 0,33-0,94; P = 0,027). Cuando los pacientes se clasificaron según la respuesta tumoral a la quimioterapia neoadyuvante, los no respondedores (Mandard Grado 4/5) tratados con quimiorradioterapia adyuvante obtuvieron un beneficio en la supervivencia (HR 0,61, i.c. del 95% 0,38-0,97; P = 0,037). En el análisis por emparejamiento por puntaje de propensión, se observó un beneficio en la supervivencia global (HR 0,62, i.c. del 95% 0,39-0,98; P = 0,042) y en la supervivencia libre de recidiva (HR 0,51.i.c. del 95% 0,30-0,87; P = 0,004) con la quimiorradioterapia adyuvante frente a no recibir tratamiento adyuvante. CONCLUSIÓN: El tratamiento adyuvante puede mejorar la supervivencia global y la supervivencia libre de recidiva en pacientes con margen de resección positivo. Este patrón parece más pronunciado con la quimiorradioterapia adyuvante en pacientes que no responden a la quimioterapia.

The effect of age on outcomes after isolated limb perfusion for advanced extremity malignancies.

BACKGROUND: Isolated limb perfusion (ILP) is a well-established treatment for patients with advanced extremity malignancies unsuitable for limb-conserving surgery. However, little is known about the outcomes of this treatment in elderly patients. We sought to determine the effects of age on the tolerability and efficacy of ILP for advanced extremity malignancy. PATIENTS AND METHODS: Patients undergoing ILP at our institution between January 2005 and January 2018 were identified from a prospectively maintained database. Patients were stratified by pathology (melanoma, soft-tissue sarcoma, other) and age (<75 years and ≥75 years). Outcomes of interest were perioperative morbidity and mortality, locoregional toxicities, response rates and oncological outcomes. RESULTS: During the study period, a total of 189 perfusions were attempted. Successful perfusions were performed in 179 patients, giving a technical success rate of 94.7%. No difference in perfusion success rates, severe locoregional toxicity and perioperative morbidity or mortality was noted between those aged <75 years and ≥75 years. The overall response rate in melanoma was 82.4%, and no difference in response rates or oncological outcomes between age groups was noted in these patients. The overall response rate in soft-tissue sarcoma was 63.5%, with no difference in response rates noted between age groups. However, patients aged <75 years with soft-tissue sarcoma had prolonged local recurrence-free survival compared with older patients (13 versus 6 months), possibly due to the prevalence of chemosensitive subtypes in the younger age group. CONCLUSION: ILP is an effective treatment for advanced extremity malignancies in the elderly, with comparable response rates and toxicities to younger patients.

Quantum molecular motion in the mixed ion-radical complex, [(H2O)(H2S)].

The cation dimer of water and hydrogen sulfide, [(H2O)(H2S)]+, serves as a fundamental model for the oxidation chemistry of H2S. The known oxidative metabolism of H2S by biological species in sulfur-rich environments has motivated the study of the inherent properties of this benchmark complex, with possible mechanistic implications for modern water oxidation chemistry. The low-energy isomer of this open-shell ion is a proton-transferred (PT) structure, H3O+SH˙. An alternative PT structure, H3S+OH˙, and a hemibonded (HB) isomer, [H2O·SH2]+, are also stable isomers, placing this complex intermediate to known (H2O)2+ (PT) and (H2S)2+ (HB) limiting regimes. This intermediate character suggested the possibility of unique molecular motion, even in the vibrational ground state. Path integral molecular dynamics and anharmonic vibrational spectroscopy simulations have been performed in this study, in order to understand the inherent quantum molecular motion of this complex. The resulting structural distributions were found to deviate significantly from both classical and harmonic analyses, including the observation of large-amplitude anharmonic motion of the central proton and nearly free rotation of the terminal hydrogens. The predicted vibrational spectra are particularly unique and suggest characteristic signatures of the strong electronic interactions and anharmonic vibrational mode couplings in this radical cation.

Isolated Limb Perfusion with Melphalan and Tumour Necrosis Factor α for In-Transit Melanoma and Soft Tissue Sarcoma.

BACKGROUND: Isolated limb perfusion (ILP) is indicated in locally advanced melanoma and soft tissue sarcoma of the extremities. This series reports the outcome of patients undergoing ILP with melphalan and tumour necrosis factor α (TNFα) at a single centre. METHODS: All patients undergoing ILP from January 2005 to January 2015 were identified from a prospectively maintained database. Those undergoing ILP for in-transit melanoma (ITM) were grouped according to disease burden: low volume and bulky (>2 cm diameter). RESULTS: A total of 143 perfusions were attempted: 9 and 134 in the upper and lower limbs, respectively. A response was assessable in 129 patients with overall response rates for ITM and sarcoma of 81.8 and 61.1 %, respectively. No difference was found in response rates between low-volume and bulky ITM. Limb salvage rates in these cohorts were 97 and 62 %. Regional toxicity following ILP was minimal with 7 grade III (5.4 %), and 1 grade V (0.8 %) reactions. Median progression-free survival was 11 months in the ITM cohort and 12 months in the sarcoma cohort. In the ITM cohort, complete responses were significantly more durable than partial responses (p = 0.0004). Median disease-specific survival was 21 months in the ITM cohort and was not reached in the sarcoma cohort. CONCLUSIONS: TNFα-based ILP is safe and provides excellent palliation of ITM due to rapid progression of systemic disease. It is less effective in sarcoma due to lower initial response rates and a lower incidence of disease dissemination.

Surgical treatment of gastrointestinal stromal tumour of the rectum in the era of imatinib.

BACKGROUND: Gastrointestinal stromal tumours (GISTs) of the rectum often require radical surgery to achieve complete resection. This study investigated the management and outcome of surgery for rectal GISTs and the role of imatinib. METHODS: A cohort study was undertaken of patients identified from a database at one tertiary sarcoma referral centre over a continuous period, from January 2001 to January 2013. RESULTS: Over 12 years, 19 patients presented with a primary rectal GIST. Median age was 57 (range 30-77) years. Neoadjuvant imatinib was used in 15 patients, significantly reducing mean tumour size from 7·6 (95 per cent c.i. 6·1 to 9·0) to 4·1 (2·8 to 5·3) cm (P < 0·001). Nine of these patients underwent surgical resection. Imatinib therapy enabled sphincter-preserving surgery to be undertaken in seven patients who would otherwise have required abdominoperineal resection or pelvic exenteration for tumour clearance. Neoadjuvant imatinib treatment also led to a significant reduction in mean(s.d.) tumour mitotic count from 16(16) to 4(9) per 50 high-power fields (P = 0·015). Imatinib was used only as adjuvant treatment in two patients. There were three deaths, all from unrelated causes. Eleven of the 13 patients who underwent resection were alive without evidence of recurrence at latest follow-up, with a median disease-free survival of 38 (range 20-129) months and overall survival of 62 (39-162) months. CONCLUSION: The use of neoadjuvant imatinib for rectal GISTs significantly decreased both tumour size and mitotic activity, which permitted less radical sphincter-preserving surgery.

Percutaneous core needle biopsy in retroperitoneal sarcomas does not influence local recurrence or overall survival.

BACKGROUND: Tumours within the retroperitoneum can cause a diagnostic dilemma. A preoperative core needle biopsy often is required to establish a histological diagnosis. Preoperative core needle biopsy for extremity soft-tissue sarcoma is oncologically safe and biopsy site recurrence is extremely rare, attributed to placing the biopsy site within the planned resection field. This study investigates whether preoperative core needle biopsy affects oncological outcomes in retroperitoneal sarcomas. METHODS: Patients undergoing resection of intermediate- and high-grade primary retroperitoneal sarcoma from 1990 until 2011 were included. Primary endpoints were immediate biopsy-related complications, local recurrence, and overall survival. RESULTS: A total of 150 patients were included in the analysis. Of these, 90 patients underwent resection after a preoperative biopsy. Median follow-up was 48 months. One patient required hospital admission postbiopsy for an abdominal wall rectus sheath haematoma. No patient developed intra-abdominal complications that required hospitalisation or early operation related to core needle biopsy. No patient developed a biopsy site recurrence. There was no significant increase in either local recurrence (p = 0.101) or overall survival (p = 0.191) after core needle biopsy. CONCLUSIONS: Preoperative core needle biopsy for retroperitoneal sarcomas is safe and does not affect oncological outcome.

Outcomes of routine ilioinguinal lymph node dissection for palpable inguinal melanoma nodal metastasis.

BACKGROUND: Patients who present with palpable inguinal melanoma nodal metastasis have two surgical options: inguinal or ilioinguinal lymph node dissection. Indications for either operation remain controversial. This study examined survival and recurrence outcomes following ilioinguinal dissection for patients with palpable inguinal nodal metastasis, and assessed the incidence and preoperative predictors of pelvic nodal metastasis. METHODS: This was a retrospective clinicopathological analysis of consecutive surgical patients with stage III malignant melanoma. All patients underwent a standardized ilioinguinal dissection at a specialist tertiary oncology hospital over a 12-year period (1998-2010). RESULTS: Some 38.9 per cent of 113 patients had metastatic pelvic nodes. Over a median follow-up of 31 months, the 5-year overall survival rate was 28 per cent for patients with metastatic inguinal and pelvic nodes, and 51 per cent for those with inguinal nodal metastasis only (P = 0.002). The nodal basin control rate was 88.5 per cent. Despite no evidence of pelvic node involvement on preoperative computed tomography (CT), six patients (5.3 per cent) with a single metastatic inguinal lymph node had metastatic pelvic lymph nodes. Logistic regression analysis showed that the number of metastatic inguinal nodes (odds ratio 1.56; P = 0.021) and suspicious CT findings (odds ratio 9.89; P = 0.001) were both significantly associated with metastatic pelvic nodes. The specificity of CT was good (89.2 per cent) in detecting metastatic pelvic nodes, but the sensitivity was limited (57.9 per cent). CONCLUSION: Metastatic pelvic nodes are common when palpable metastatic inguinal nodes are present. Long-term survival can be achieved following their resection by ilioinguinal dissection. As metastatic pelvic nodes cannot be diagnosed reliably by preoperative CT, patients presenting with palpable inguinal nodal metastasis should be considered for ilioinguinal dissection.

Surgical resection for non-familial adenomatous polyposis-related intra-abdominal fibromatosis.

BACKGROUND: Intra-abdominal fibromatosis (IAF) in the context of familial adenomatosis polyposis (FAP) is associated with significant morbidity and high recurrence rates after surgical resection. Non-surgical treatments are therefore advocated. This study explored outcomes in patients with IAF not associated with FAP who underwent surgical resection. METHODS: Data were analysed from a prospectively collected database at a sarcoma tertiary referral centre. RESULTS: From 2001 to 2011, 15 patients without FAP underwent primary curative surgical resection of IAF. Their median (range) age was 42 (19-64) years. Median tumour size was 18 (8.5-25) cm and weight 1306 (236-2228) g. Complete macroscopic clearance was obtained in all patients. There were no deaths in hospital or within 30 days and only one patient developed a major complication. Median follow-up was 40 (6-119) months. During follow-up two patients developed a recurrence after a disease-free interval of 12 and 16 months. CONCLUSION: In contrast to FAP-associated IAF, non-FAP-associated IAF has a very low recurrence rate after surgical resection. Surgical resection is therefore advocated as first-line treatment in patients with non-FAP-associated IAF when resection can be performed with low morbidity.

A set of plastid DNA-specific universal primers for flowering plants.

MatKand rbcL are recommended as the official barcode loci for higher plants but there remains a need for additional universal markers. We generated a series of 84 new universal primers targeting 42 plastid loci that all yielded single amplicons when applied to DNA templates from 19 diverse higher plant families. Marker utility ultimately depends on sequence variability, with rapidly evolving loci being useful for barcoding or biogeographic applications and more conserved loci being better suited to deep phylogeny reconstruction. Whereas excessive size variation is undesirable for many applications, modest size variability caused by indels and the sequence variation frequently associated with indels are highly desirable. We therefore performed a quick screen of the markers for size and sequence variation using pooled DNA templates from 96 taxonomically diverse species. All markers produced little or no size variation (consistent with the presence of minor indels). The seven regions exhibiting most size variation in pooled (rpl23&rpl2.1, 16S, 23S, 4.5S&5S, petB&D, and rpl2, rpoCl and trnK introns) were then amplified for all species individually, confirming the pooled template results. When the most variable loci (introns of trnK and rpoC1) were sequenced for all 96 species, a high level of sequence variation (nucleotide substitutions and indels) was observed among congeneric species groups for both loci. Both markers therefore have potential as supplementary barcode markers.

Adaptive divergence and speciation among sexual and pseudoviviparous populations of Festuca.

Pseudovivipary is an environmentally induced flowering abnormality in which vegetative shoots replace seminiferous (sexual) inflorescences. Pseudovivipary is usually retained in transplantation experiments, indicating that the trait is not solely induced by the growing environment. Pseudovivipary is the defining characteristic of Festuca vivipara, and arguably the only feature separating this species from its closest seminiferous relative, Festuca ovina. We performed phylogenetic and population genetic analysis on sympatric F. ovina and F. vivipara samples to establish whether pseudovivipary is an adaptive trait that accurately defines the separation of genetically distinct Festuca species. Chloroplast and nuclear marker-based analyses revealed that variation at a geographical level can exceed that between F. vivipara and F. ovina. We deduced that F. vivipara is a recent species that frequently arises independently within F. ovina populations and has not accumulated significant genetic differentiation from its progenitor. We inferred local gene flow between the species. We identified one amplified fragment length polymorphism marker that may be linked to a pseudovivipary-related region of the genome, and several other markers provide evidence of regional local adaptation in Festuca populations. We conclude that F. vivipara can only be appropriately recognized as a morphologically and ecologically distinct species; it lacks genetic differentiation from its relatives. This is the first report of a 'failure in normal flowering development' that repeatedly appears to be adaptive, such that the trait responsible for species recognition constantly reappears on a local basis.

Rapeseed cytoplasm gives advantage in wild relatives and complicates genetically modified crop biocontainment.

Biocontainment methods for genetically modified crops closest to commercial reality (chloroplast transformation, male sterility) would be compromised (in absolute terms) by seed-mediated gene flow leading to chloroplast capture. Even in these circumstances, however, it can be argued that biocontainment still represses transgene movement, with the efficacy depending on the relative frequency of seed- and pollen-mediated gene flow. In this study, we screened for crop-specific chloroplast markers from rapeseed (Brassica napus) amongst sympatric and allopatric populations of wild B. oleracea in natural cliff-top populations and B. rapa in riverside and weedy populations. We found only modest crop chloroplast presence in wild B. oleracea and in weedy B. rapa, but a surprisingly high incidence in sympatric (but not in allopatric) riverside B. rapa populations. Chloroplast inheritance models indicate that elevated crop chloroplast acquisition is best explained if crop cytoplasm confers selective advantage in riverside B. rapa populations. Our results therefore imply that chloroplast transformation may slow transgene recruitment in two settings, but actually accelerate transgene spread in a third. This finding suggests that the appropriateness of chloroplast transformation for biocontainment policy depends on both context and geographical location.

Frosty pod of cacao: a disease with a limited geographic range but unlimited potential for damage.

ABSTRACT Moniliophthora roreri, the cause of frosty pod rot (FP), is a specialized fungal pathogen (family Marasmiaceae) that invades only actively growing pods of cacao, Theobroma cacao, and related species of Theobroma and Herrania. FP damages pods and the commercially important seeds that some of these species produce. M. roreri was confined to northwestern South America until the 1950s. Its appearance in Panama in 1956 signaled a change in its geographic distribution. Now, it is found in 11 countries in tropical America. The fungus is currently in an active dispersal phase, possibly due to an increase in human-mediated spread. FP is more destructive than black pod (Phytophthora spp.) and more dangerous and difficult to control than witches' broom, caused by Moniliophthora (Crinipellis) perniciosa. The aggressiveness of M. roreri, its capacity to survive different environmental conditions, its rapid natural dispersal, its propensity for man-mediated dispersal, and the susceptibility of most commercial cacao genotypes, all indicate that FP presents a substantial threat to cacao cultivation worldwide.

Assembling spatially explicit landscape models of pollen and spore dispersal by wind for risk assessment.

Models of windblown pollen or spore movement are required to predict gene flow from genetically modified (GM) crops and the spread of fungal diseases. We suggest a simple form for a function describing the distance moved by a pollen grain or fungal spore, for use in generic models of dispersal. The function has power-law behaviour over sub-continental distances. We show that air-borne dispersal of rapeseed pollen in two experiments was inconsistent with an exponential model, but was fitted by power-law models, implying a large contribution from distant fields to the catches observed. After allowance for this 'background' by applying Fourier transforms to deconvolve the mixture of distant and local sources, the data were best fit by power-laws with exponents between 1.5 and 2. We also demonstrate that for a simple model of area sources, the median dispersal distance is a function of field radius and that measurement from the source edge can be misleading. Using an inverse-square dispersal distribution deduced from the experimental data and the distribution of rapeseed fields deduced by remote sensing, we successfully predict observed rapeseed pollen density in the city centres of Derby and Leicester (UK).

Fitness of hybrids between rapeseed (Brassica napus) and wild Brassica rapa in natural habitats.

Fitness of hybrids between genetically modified (GM) crops and wild relatives influences the likelihood of ecological harm. We measured fitness components in spontaneous (non-GM) rapeseed x Brassica rapa hybrids in natural populations. The F1 hybrids yielded 46.9% seed output of B. rapa, were 16.9% as effective as males on B. rapa and exhibited increased self-pollination. Assuming 100% GM rapeseed cultivation, we conservatively predict < 7000 second-generation transgenic hybrids annually in the United Kingdom (i.e. approximately 20% of F1 hybrids). Conversely, whilst reduced hybrid fitness improves feasibility of bio-containment, stage projection matrices suggests broad scope for some transgenes to offset this effect by enhancing fitness.

On the structural differences between markers and genomic AC microsatellites.

AC microsatellites have proved particularly useful as genetic markers. For some purposes, such as in population biology, the inferences drawn depend on the quantitative values of their mutation rates. This, together with intrinsic biological interest, has led to widespread study of microsatellite mutational mechanisms. Now, however, inconsistencies are appearing in the results of marker-based versus non-marker-based studies of mutational mechanisms. The reasons for this have not been investigated, but one possibility, pursued here, is that the differences result from structural differences between markers and genomic microsatellites. Here we report a comparison between the CEPH AC marker microsatellites and the global population of AC microsatellites in the human genome. AC marker microsatellites are longer than the global average. Controlling for length, marker microsatellites contain on average fewer interruptions, and have longer segments, than their genomic counterparts. Related to this, marker microsatellites show a greater tendency to concentrate the majority of their repeats into one segment. These differences plausibly result from scientists selecting markers for their high polymorphism. In addition to the structural differences, there are differences in the base composition of flanking sequences, marker flanking regions being richer in C and G and poorer in A and T. Our results indicate that there are profound differences between marker and genomic microsatellites that almost certainly affect their mutation rates. There is a need for a unified model of mutational mechanisms that accounts for both marker-derived and genomic observations. A suggestion is made as to how this might be done.

Ty1-copia retrotransposon-based SSAP marker development in cashew (Anacardium occidentale L.).

The most popular retrotransposon-based molecular marker system in use at the present time is the sequence-specific amplification polymorphism (SSAP) system . This system exploits the insertional polymorphism of long terminal repeat (LTR) retrotransposons around the genome. Because the LTR sequence is used to design primers for this method, its successful application requires sequence information from the terminal region of the mobile elements . In this study, two LTR sequences were isolated from the cashew genome and used successfully to develop SSAP marker systems. These were shown to have higher levels of polymorphism than amplified fragment length polymorphic markers for this species.