Primary cutaneous melanoma. Optimized cutoff points of tumor thickness and importance of Clark's level for prognostic classification

Correlation Analyses between Histological Staging and Molecular Alterations in Tumor-Derived and Cell-Free DNA of Early-Stage Primary Cutaneous Melanoma

Here, we investigate the correlation and statistical analyses between histological staging and molecular alterations in tumor-derived (tdDNA) and cell-free DNA (cfDNA) obtained from early-stage primary cutaneous melanoma (PCM) patients using digital PCR (dPCR) for the detection of the BRAF p.V600E somatic pathogenic variant. In the prospective study, a total of 68 plasma and paired tdDNA samples, and in the retrospective cohort, a total of 100 tdDNA samples were analyzed using dPCR and reverse hybridization StripAssay. The Breslow depth (BD) and Clark level were applied to categorize the study population. Our results demonstrate that dPCR is a highly sensitive and specific method for the detection of BRAF p.V600E somatic variants in cfDNA samples from PCM patients. A strong correlation was detected between BD and cfDNA concentration in all mutant and negative cases, between the tdDNA concentration and the tumor-derived variant allele frequency (VAF) of BRAF p.V600E, between the tdVAF and the cfVAF in all cases, and between the cfDNA and cfVAF in mutant cases. The tdVAF and cfVAF of BRAF p.V600E and cfDNA concentration were the highest in Clark's V category. The cfDNA concentration was statistically significantly higher in Clark's III, IV, and V groups compared to cases with a better prognosis. It can also be explained by the fact that cases with a more advanced stage classification release more cfDNA into the peripheral circulation.

Prognostic impact of Breslow thickness in acral melanoma: A retrospective analysis

BACKGROUND

Evidence for the prognostic importance of tumor thickness in acral melanoma (AM) patients is limited.

OBJECTIVE

The objective of the study was to determine the prognostic impact of Breslow thickness in AM.

METHODS

This multicenter study enrolled patients diagnosed with localized AM between January 1, 2000 and December 31, 2017. Melanoma-specific survival (MSS) in different tumor thickness strata (T1-T4: ≤1, >1-2, >2-4, >4 mm, respectively) was estimated by the Kaplan-Meier method. Comparisons were performed by the log-rank test and multivariable Cox regression.

RESULTS

A total of 853 patients with clinical N0 (cN0) AM were included in the analysis. The median follow-up time was 60.1 months. The median MSS in patients with T1-T4 disease was not reached, 111.0, 92.8, and 67.1 months, respectively. MSS differed significantly among cN0 patients with T1-T3 AM (log-rank P = .004, .012, <0.001 for T1 vs T2, T2 vs T3, and T1 vs T3, respectively); however, there was no significant difference between T3 and T4 AM (hazard ratio = 0.82, 95% CI, 0.62-1.09). Six-subgroup analyses confirmed that survival outcomes were similar between different subgroups with tumor thickness >2 mm.

LIMITATIONS

The limitations were retrospective design and some missing variables.

CONCLUSIONS

There was no association between tumor thickness and survival in AM patients with a Breslow thickness >2 mm.

Clinicopathological characteristics and prognosis in significantly thick acral lentiginous melanoma in Taiwan

This retrospective cohort study enrolled 385 patients diagnosed with cutaneous melanoma from 1980 to 2021 in National Taiwan University Hospital (NTUH). The aim of this study was to investigate the relationship between thickness of primary melanoma lesions and disease outcome of melanoma patients, in particular, those diagnosed with acral lentiginous melanoma (ALM). The association between important clinicopathological characteristics other than tumor thickness and disease outcome was also analyzed. Survival analyses with the Kaplan-Meier method were utilized to investigate the prognoses of patients with different lesion thickness. The male-to-female ratio was 1.12:1. The median age at diagnosis was 63 years old (mean: 62.2 years). There were 283 cases (73.5%) of acral lentiginous melanoma (ALM) with a male-to-female ratio of 1.04:1. Between patients with primary ALM lesions 4.1 millimeters (mm) to 8.0 mm thick and those with lesions over 8.0 mm thick, significant differences in prognostic outcomes including incidence of second recurrences within 1 year (raw p = 0.003, Bonferroni corrected p = 0.009) and distant metastases within 1 year (raw p = 0.003, Bonferroni corrected p = 0.008), were observed. Significantly worse 1-year (raw p = 0.01, Bonferroni corrected p=0.03) and 2-year survival (raw p = 0.006, Bonferroni corrected p = 0.02) were found in ALM patients with lesions of over 8 mm thick than those with lesions 4.1 mm to 8.0 mm at diagnosis. Vigilant short-term follow-up is warranted in ALM patients with lesions of over 8.0 mm thick at diagnosis due to higher risks of adverse outcome.

Risk prediction in cutaneous melanoma patients from their clinico-pathological features: superiority of clinical data over gene expression data

Risk assessment in cutaneous melanoma (CM) patients is one of the major challenges in the effective treatment of CM patients. Traditionally, clinico-pathological features such as Breslow thickness, American Joint Committee on Cancer (AJCC) tumor staging, etc. are utilized for this purpose. However, due to advancements in technology, most of the upcoming risk prediction methods are gene-expression profile (GEP) based. In this study, we have tried to develop new GEP and clinico-pathological features-based biomarkers and assessed their prognostic strength in contrast to existing prognostic methods. We developed risk prediction models using the expression of the genes associated with different cancer-related pathways and got a maximum hazard ratio (HR) of 2.52 with p-value ~10-8 for the apoptotic pathway. Another model, based on combination of apoptotic and notch pathway genes boosted the HR to 2.57. Next, we developed models based on individual clinical features and got a maximum HR of 2.45 with p-value ~10-6 for Breslow thickness. We also developed models using the best features of clinical as well as gene-expression data and obtained a maximum HR of 3.19 with p-value ~10-9. Finally, we developed a new ensemble method using clinical variables only and got a maximum HR of 6.40 with p-value ~10-15. Based on this method, a web-based service and an android application named 'CMcrpred' is available at (https://webs.iiitd.edu.in/raghava/cmcrpred/) and Google Play Store respectively to facilitate scientific community. This study reveals that our new ensemble method based on only clinico-pathological features overperforms methods based on GEP based profiles as well as currently used AJCC staging. It also highlights the need to explore the full potential of clinical variables for prognostication of cancer patients.

Computing Skin Cutaneous Melanoma Outcome From the HLA-Alleles and Clinical Characteristics

Human leukocyte antigen (HLA) are essential components of the immune system that stimulate immune cells to provide protection and defense against cancer. Thousands of HLA alleles have been reported in the literature, but only a specific set of HLA alleles are present in an individual. The capability of the immune system to recognize cancer-associated mutations depends on the presence of a particular set of alleles, which elicit an immune response to fight against cancer. Therefore, the occurrence of specific HLA alleles affects the survival outcome of cancer patients. In the current study, prediction models were developed, using 401 cutaneous melanoma patients, to predict the overall survival (OS) of patients using their clinical data and HLA alleles. We observed that the presence of certain favorable superalleles like HLA-B∗55 (HR = 0.15, 95% CI 0.034-0.67), HLA-A∗01 (HR = 0.5, 95% CI 0.3-0.8), is responsible for the improved OS. In contrast, the presence of certain unfavorable superalleles such as HLA-B∗50 (HR = 2.76, 95% CI 1.284-5.941), HLA-DRB1∗12 (HR = 3.44, 95% CI 1.64-7.2) is responsible for the poor survival. We developed prediction models using key 14 HLA superalleles, demographic, and clinical characteristics for predicting high-risk cutaneous melanoma patients and achieved HR = 4.52 (95% CI 3.088-6.609, p-value = 8.01E-15). Eventually, we also provide a web-based service to the community for predicting the risk status in cutaneous melanoma patients (https://webs.iiitd.edu.in/raghava/skcmhrp/).

Melanoma of the eyelid and periocular skin: Histopathologic classification and molecular pathology

Cutaneous melanoma, a potentially lethal malignancy of the periocular skin, represents only a small proportion of the roughly 87,000 new cases of cutaneous melanoma diagnosed annually in the United States. Most of our understanding of melanoma of the eyelid skin is extrapolated from studies of cutaneous melanoma located elsewhere. Recent years have witnessed major breakthroughs in molecular biology and genomics of cutaneous melanoma, some of which have led to the development of targeted therapies. The molecular insights have also kindled interest in rethinking how cutaneous melanomas are classified and assessed for risk. We provide a synopsis of the epidemiology, histopathologic classification, and clinical experience of eyelid melanoma since 1990 and then review major advances in the molecular biology of cutaneous melanoma, exploring how this impacts our understanding of classification and predicting risk.

Immunohistochemical Study of Pepsinogen C Expression in Cutaneous Malignant Melanoma: Association with Clinicopathological Parameters

Background

The aim of this study was to evaluate the pepsinogen C expression in malignant cutaneous melanomas and analyze its possible relationship to clinical and pathological parameters. Pepsinogen C is an aspartyl proteinase primarily involved in the digestion of proteins in the stomach and represents one of the main androgen-inducible proteins in breast cancer cells.

Method

Tumoral pepsinogen C expression was retrospectively analyzed in 35 paraffin-embedded tissues from patients with primary malignant cutaneous melanoma and in 10 samples from 10 benign lesions (4 dermal melanocytic nevi, 4 compound melanocytic nevi and 2 dysplastic melanocytic nevi), using immunohistochemical methods.

Results

The benign lesions were consistently negative for pepsinogen C, whereas 20 of the 35 malignant melanomas (57%) showed positive immunostaining for pepsinogen C. The percentage of pepsinogen C-positive tumors was significantly higher in men than in women (p=0.01) and in epithelioid melanomas than in fusocellular or mixed type melanomas (p=0.003). In addition, the percentage of pepsinogen-C positive tumors was positively and significantly correlated with lesion thickness (p=0.003), Clark's level of invasion (p=0.028) and tumor stage (p<0.001).

Conclusion

Pepsinogen C could be a new prognosticator of unfavorable outcome in cutaneous malignant melanoma.

Malignant Melanoma of the Nipple: A Case Report

Malignant melanoma rarely originates from the female nipple. Tumors that develop on the skin of the breast are often subject to a delayed diagnosis. Cytologic examination provides excellent diagnostic capabilities and is a safe procedure with a lower risk of local implantation, compared to needle or incisional biopsy. We herein report a patient who underwent surgical resection of a primary malignant melanoma of the nipple. An elastic soft nodule was observed on the left nipple, and no abnormal lesions were identified in the breast. Eventually, a malignant melanoma was diagnosed from the clinical and cytological evaluation findings. This bulky tumor was classified as a stage IIIC nodular melanoma, with a thickness of 12 mm. The patient received adjuvant chemotherapy and exhibits no evidence of recurrence 7 years after surgery.

Sox2 is dispensable for primary melanoma and metastasis formation

Tumor initiation and metastasis formation in many cancers have been associated with emergence of a gene expression program normally active in embryonic or organ-specific stem cells. In particular, the stem cell transcription factor Sox2 is not only expressed in a variety of tumors, but is also required for their formation. Melanoma, the most aggressive skin tumor, derives from melanocytes that during development originate from neural crest stem cells. While neural crest stem cells do not express Sox2, expression of this transcription factor has been reported in melanoma. However, the role of Sox2 in melanoma is controversial. To study the requirement of Sox2 for melanoma formation, we therefore performed CRISPR-Cas9-mediated gene inactivation in human melanoma cells. In addition, we conditionally inactivated Sox2 in a genetically engineered mouse model, in which melanoma spontaneously develops in the context of an intact stroma and immune system. Surprisingly, in both models, loss of Sox2 did neither affect melanoma initiation, nor growth, nor metastasis formation. The lack of a tumorigenic role of Sox2 in melanoma might reflect a distinct stem cell program active in neural crest stem cells and during melanoma formation.

How our practice of histopathology, especially tumour pathology has changed in the last two decades: reflections from a major referral center in Pakistan

Continued advances in the field of histo-pathology (and cyto-pathology) over the past two decades have resulted in dramatic changes in the manner in which these disciplines are now practiced. This is especially true in the setting of a large university hospital where the role of pathologists as clinicians (diagnosticians), undergraduate and postgraduate educators, and researchers has evolved considerably. The world around us has changed significantly during this period bringing about a considerable change in our lifestyles and the way we live. This is the world of the internet and the world-wide web, the world of Google and Wikipedia, of Youtube and Facebook where anyone can obtain any information one desires at the push of a button. The practice of histo (and cyto) pathology has also evolved in line with these changes. For those practicing this discipline in a poor, developing country these changes have been breathtaking. This is an attempt to document these changes as experienced by histo (and cyto) pathologists practicing in the biggest center for Histopathology in Pakistan, a developing country in South Asia with a large (180 million) and ever growing population. The Section of Histopathology, Department of Pathology and Microbiology at the Aga Khan University Hospital (AKUH) in Karachi, Pakistan's largest city has since its inception in the mid-1980s transformed the way histopathology is practiced in Pakistan by incorporating modern methods and rescuing histopathology in Pakistan from the primitive and outdated groove in which it was stuck for decades. It set histopathology in Pakistan firmly on the path of modernity and change which are essential for better patient management and care through accurate and complete diagnosis and more recently prognostic and predictive information as well.

Staging and prognosis of cutaneous melanoma

Staging of cutaneous melanoma continues to evolve through identification and rigorous analysis of potential prognostic factors. In 1998, the American Joint Committee on Cancer (AJCC) Melanoma Staging Committee developed the AJCC melanoma staging database, an international integrated compilation of prospectively accumulated melanoma outcome data from several centers and clinical trial cooperative groups. Analysis of this database resulted in major revisions to the TNM staging system reflected in the sixth edition of the AJCC Cancer Staging Manual published in 2002. More recently, the committee's analysis of an updated melanoma staging database, including prospective data on more than 50,000 patients, led to staging revisions adopted in the seventh edition of the AJCC Cancer Staging Manual published in 2009. This article highlights these revisions, reviews relevant prognostic factors and their impact on staging, and discusses emerging tools that will likely affect future staging systems and clinical practice.

Clinical guidelines for the recognition of melanoma of the foot and nail unit

Malignant melanoma is a life threatening skin tumour which may arise on the foot. The prognosis for the condition is good when lesions are diagnosed and treated early. However, lesions arising on the soles and within the nail unit can be difficult to recognise leading to delays in diagnosis. These guidelines have been drafted to alert health care practitioners to the early signs of the disease so an early diagnosis can be sought.

Predicting survival outcome of localized melanoma: an electronic prediction tool based on the AJCC Melanoma Database

BACKGROUND

We sought to develop a reliable and reproducible statistical model to predict the survival outcome of patients with localized melanoma.

METHODS

A total of 25,734 patients with localized melanoma from the 2008 American Joint Committee on Cancer (AJCC) Melanoma Database were used for the model development and validation. The predictive model was developed from the model development data set (n = 14,760) contributed by nine major institutions and study groups and was validated on an independent model validation data set (n = 10,974) consisting of patients from a separate melanoma center. Multivariate analyses based on the Cox model were performed for the model development, and the concordance correlation coefficients were calculated to assess the adequacy of the predictive model.

RESULTS

Patient characteristics in both data sets were virtually identical, and tumor thickness was the single most important prognostic factor. Other key prognostic factors identified by stratified analyses included ulceration, lesion site, and patient age. Direct comparisons of the predicted 5- and 10-year survival rates calculated from the predictive model and the observed Kaplan-Meier 5- and 10-year survival rates estimated from the validation data set yielded high concordance correlation coefficients of 0.90 and 0.93, respectively. A Web-based electronic prediction tool was also developed ( http://www.melanomaprognosis.org/ ).

CONCLUSIONS

This is the first predictive model for localized melanoma that was developed based on a very large data set and was successfully validated on an independent data set. The high concordance correlation coefficients demonstrated the accuracy of the predicted model. This predictive model provides a clinically useful tool for making treatment decisions, for assessing patient risk, and for planning and analyzing clinical trials.

Creation and test of a questionnaire for self-assessment of melanoma risk factors

The objective of this study was to create a self-administrated questionnaire for people to enable them to assess their own melanoma risk factors. To test the validity of this questionnaire in a large prospective study, the answers given by the patient were systematically checked by his or her general practitioner. In this prospective study, the choice of questions was based on a review of the literature. The validity of the questionnaire was assessed by testing 1500 consecutive patients attending a consultation with their general practitioner. Considerable variations concerning the prevalence of different melanoma risk factors were noticed in the population: 44.1% had a phototype I or II, 41% had severe sunburn during infancy, 29.9% had freckling tendency, 22% had more than 50 naevi and 1.4% a personal history of melanoma. In total, 45% had more than one melanoma risk factor. The accuracy of the answers given by the patients was assured by the correction given by their general practitioners. The percentage of correct answers given by the patients was 79.9% for the phototype, 90.6% for freckling tendency, 86.6% for the number of naevi, 96.5% for severe sunburn during infancy and 98.1 and 95.8% for personal and familial history of melanoma. This study confirms that individuals with multiple risk factors for melanoma are common among patients consulting their general practitioners. Furthermore, self-screening with the self-assessment questionnaire is easily feasible and is accurate for identifying high-risk individuals. This tool might be useful for carrying out melanoma-targeted screening.

Cutaneous Melanomas of the Eyelid

Cutaneous eyelid melanomas are very rare lesions. The lentiginous subtypes are the most frequent melanocytic lesions of the eyelid and can be likened to conjunctival melanocytic lesions like PAM, PAM with atypia and conjunctival melanoma. Compared to melanomas elsewhere on the body, eyelid melanomas have special considerations. Eyelid skin is very thin, the mucocutaneous junction at the lid margin can affect prognosis, the lymphatic drainage pattern is very variable and there is an inherent difficulty to excise wide margins without sacrificing important structures. A customized excision approach, using tissue-sparing "Slow-Mohs" technique, is suggested. Sentinel lymph node dissection has an evolving therapeutic role but remains controversial.

Long-Term Survival in Metastatic Melanoma Patients Treated with Sequential Biochemotherapy: Report of a Phase II Study

The overall survival for patients with metastatic melanoma is very poor, with a median survival of 8.5 months. In this Phase II trial, we assessed the efficacy, safety, and tolerability of a sequential biochemotherapy schedule, using dacarbazine as antiblastic agent and immunomodulant doses of interleukin-2 and interferon-alfa. Thirty-one eligible patients with metastatic melanoma received dacarbazine IV as antiblastic therapy and interluekin-2, plus interferon-alfa SC as sequential immunotherapy, for 6 months. Responding and nonprogressing patients were subsequently maintained on immunotherapy treatment for further 6 months. Twenty-nine patients had an adequate trial, and were assessable for both response and toxicities, with a median follow-up of 49 months. The overall response rate was 52 percent (3 CR and 12 PR), SD was 8 (27 percent) and PD were achieved in 6 patients (21 percent). The median survival duration of responders was 28 months, significantly longer (p < 0.001) than the 16 months of nonresponders. Therapy was well tolerated and produced a significant improvement in progressive-free survival. Further studies, thus, are recommended for larger groups of patients not only to confirm these results, but also to apply this biochemotherapy regimen as adjuvant postsurgical treatment in early stages of malignant melanoma.

Melanoma prognostic factors found in the dermatopathology report

Significant prognostic information is available in a routine melanoma dermatopathology report. Features that are enumerated in the pathology report and that portend a potentially poorer prognosis are older age, site (acral, head, neck), male sex, increasing Breslow tumor thickness, increasing Clark's level, ulceration, increasing number of mitoses, vertical growth phase, regression, absence of a host inflammatory response, increased tumor vascularity, angiotropism, vascular invasion, neurotropism, marked atypia, and satellite metastasis.

Melanoma epidemiology and trends

Rising incidence rates of cutaneous melanoma have been observed during the last four decades in white populations worldwide. The cancer statistics in the United States have revealed 6 cases per 100,000 and year at the beginning of the 1970s and 18 cases per 100,000 inhabitants and year at the beginning of 2000, demonstrating a threefold increase in incidence rates. Incidence rates in central Europe increased in the same time period from 3 to 4 cases to 10 to 15 cases per 100,000 inhabitants and year, which is very similar to the increase in the United States. Cohort studies from several countries indicate that the trend of increasing incidence rates will continue in the future for at least the next 2 decades; thus, an additional doubling of incidence rates is expected. The highest incidence rates have been reported from Australia and New Zealand, from 40 to 60 cases per 100,000 inhabitants and year. Mortality rates likewise slightly increased in the United States and in Europe during the 1970s and 1980s. In the 1990 s, however, a leveling off of mortality rates was observed in many countries. Simultaneously, a clear decrease of Breslow tumor thickness was reported in the United States and European countries. This development indicates improved early recognition of cutaneous melanoma, which is presently the main factor for a more favorable prognosis.

Lack of cytoplasmic ERK activation is an independent adverse prognostic factor in primary cutaneous melanoma

The aim of this study was to estimate the impact on survival of NRAS and BRAF mutations and activation of Akt and extracellular signal-regulated kinase (ERK) in primary melanomas. A cohort of 57 primary cutaneous T1-2 melanoma tumors was analyzed. Mutation frequency for both genes was 61% (NRAS 26% and BRAF 39%). In a univariate analysis, shorter overall survival was associated with the presence of ulceration (P=0.001) and BRAF exon 15 mutations (P=0.005) as well as the absence of nuclear activation of Akt (P=0.022) and of cytoplasmic activation of ERK (P=0.003). Unexpectedly, ulceration was a significant adverse prognostic factor only in melanomas with BRAF mutations, whereas there was no effect of ulceration on overall survival in tumors with wild-type BRAF. A multivariate analysis showed that significant independent adverse survival prognostic markers were absence of cytoplasmic activation of ERK (P=0.007) and ulceration (P=0.008), whereas BRAF exon 15 mutation status showed a nonsignificant trend (P=0.066). The absence of cytoplasmic ERK activation in poor prognosis T1-2 melanomas may be associated with activation of some other uncharacterized pathway leading to tumor progression and adverse outcome. Immunohistochemical analysis of cytoplasmic phosphorylated ERK could be used as a prognostic marker in primary melanomas if confirmed in another data set.

An Integrated Tree-Based Classification Approach to Prognostic Grouping with Application to Localized Melanoma Patients

We propose an integrated tree-based approach for prognostic grouping of localized melanoma patients. This approach incorporates the survival tree model with the agglomerative hierarchical clustering to group terminal subgroups with similar prognoses together. The Brier score is used to evaluate the goodness of fit and the k-fold cross-validation test is used to evaluate the reproducibility of the scheme for prediction. The proposed approach is applied to an American Joint Committee on Cancer (AJCC) localized melanoma data set and compared with the current AJCC staging system. This approach performs more efficiently than the standard tree methods and has made improvement over the current AJCC melanoma staging system.

Gene expression signatures for tumor progression, tumor subtype, and tumor thickness in laser-microdissected melanoma tissues

PURPOSE

To better understand the molecular mechanisms of malignant melanoma progression and metastasis, gene expression profiling was done of primary melanomas and melanoma metastases.

EXPERIMENTAL DESIGN

Tumor cell-specific gene expression in 19 primary melanomas and 22 melanoma metastases was analyzed using oligonucleotide microarrays after laser-capture microdissection of melanoma cells. Statistical analysis was done by random permutation analysis and support vector machines. Microarray data were further validated by immunohistochemistry and immunoblotting.

RESULTS

Overall, 308 genes were identified that showed significant differential expression between primary melanomas and melanoma metastases (false discovery rate<or=0.05). Significantly overrepresented gene ontology categories in the list of 308 genes were cell cycle regulation, mitosis, cell communication, and cell adhesion. Overall, 47 genes showed up-regulation in metastases. These included Cdc6, Cdk1, septin 6, mitosin, kinesin family member 2C, osteopontin, and fibronectin. Down-regulated genes included E-cadherin, fibroblast growth factor binding protein, and desmocollin 1 and desmocollin 3, stratifin/14-3-3sigma, and the chemokine CCL27. Using support vector machine analysis of gene expression data, a performance of >85% correct classifications for primary melanomas and metastases was reached. Further analysis showed that subtypes of primary melanomas displayed characteristic gene expression patterns, as do thin tumors (<or=1.0 mm Breslow thickness) compared with intermediate and thick tumors (>2.0 mm Breslow thickness).

CONCLUSIONS

Taken together, this large-scale gene expression study of malignant melanoma identified molecular signatures related to metastasis, melanoma subtypes, and tumor thickness. These findings not only provide deeper insights into the pathogenesis of melanoma progression but may also guide future research on innovative treatments.

Diagnosis and treatment of cutaneous melanoma: state of the art 2006*

Although the incidence of melanoma is still rising in Caucasian populations, the increase in mortality has leveled off. Improvements in early diagnosis, with more frequent diagnosis of low-risk patients (i.e. those with <1 mm of tumor thickness), is the main reason for these divergent developments. Primary prevention has not yet been successful and recent studies have demonstrated the lack of effectiveness of sunscreen in preventing nevi in children. Progress was made in early melanoma diagnosis when dermoscopy and digital dermoscopy were introduced, and computer algorithms have proved to be highly efficacious for automated melanoma diagnosis. Primary melanomas are now excised with narrower surgical margins of 1-2 cm. Sentinel-node biopsy is recommended as a nodal staging procedure in patients with tumor thickness of 1 mm and more, but the prognostic impact of this procedure has not yet been demonstrated. New imaging techniques, e.g. whole-body MRI and PET-CT, provide more accurate staging, particularly in patients with apparent metastasis, and facilitate decisions on surgical treatment strategies. Staging is now based on the 2001 TNM classification including tumor thickness and histopathologic ulceration in stages I and II and lymph node micro and macro-metastasis in stage III. A stage- and risk-adopted follow-up schedule is proposed for melanoma surveillance. Adjuvant therapy with interferon-alpha in high-risk patients offers a small benefit in terms of recurrence-free and overall survival; the optimal dosage and duration of this treatment are still to be defined. Almost no progress has been made in the medical treatment of disseminated metastasis of melanoma. Therapy with dacarbazine and a few other single agents remains the first-line treatment approach of choice. A number of new treatment modalities, including targeted molecules and immunologic approaches with monoclonal antibodies, are under development; hopefully, new treatment modalities will be available in the near future.

Malignant Melanoma in Turkey: A Single Institution's Experience on 475 Cases

BACKGROUND

This study was performed to determine the characteristics and the clinical outcomes of patients with cutaneous melanoma in Turkey.

METHODS

The medical records of patients between 1991 and 2003 at Institute of Oncology were retrieved from the cancer registry.

RESULTS

Of the 475 adult cases with complete staging procedure, the incidence of localized (stages I-II) disease was 301 (63.4%), and followed by node involved (stage III) and metastatic (stage IV) disease with the incidence of 117 (24.6%) and 57 (12.0%), respectively. The median age of patients was 50 years (17-104 years) and male/female ratio was 1.1. Of 206 patients (43.4%) the diseases were located on extremities, 150 (31.6%) on the trunk, and 102 (21.5%) on the head and neck region. In cases with early/node negative stage, stage distribution was identical. The superficial spreading type was the commonest histology (52.2%). The Breslow thickness distributed equally, whereas tumor invasion aggregated mainly at Clark level III and IV. Half of the lesions were ulcerated and with low mitotic potential. In cases with the node involved stage, the majority of patients had only one lymph node involved. In metastatic patients, two thirds had distant metastases including lung metastases and half of them had single metastatic region. With the median follow-up of all patients of 5.2 years, the median overall survival of all patients was 62.2 months and the 5-year overall survival was 50.5%. Overall survival was significantly negatively correlated with male (P<0.001), advanced stages (P<0.001) and old ages (P=0.005). The five-year survival rates of patients with stages I-II and III disease were 63.6% and 36.6%, respectively. Nodular histology subtype, deeper Breslow tumor depth, extensive invasion, presence of ulceration, advanced stage, presence of relapse, being male and elderly patient, presence of visceral recurrence, and high mitotic activity were found to be associated with poor prognosis for overall survival in localized disease. The median survival of metastatic patients was 9.9 months and 1-year overall survival rate was 32.7%. Unresponsiveness to chemotherapy, visceral metastasis, multiple metastases and not given chemotherapy were the poor prognostic factors for overall survival.

CONCLUSION

The descriptive and prognostic factors in Turkey are similar to those in Western countries.

Quantitative assessment of tumour extraction from dermoscopy images and evaluation of computer-based extraction methods for an automatic melanoma diagnostic system

The aims of this study were to provide a quantitative assessment of the tumour area extracted by dermatologists and to evaluate computer-based methods from dermoscopy images for refining a computer-based melanoma diagnostic system. Dermoscopic images of 188 Clark naevi, 56 Reed naevi and 75 melanomas were examined. Five dermatologists manually drew the border of each lesion with a tablet computer. The inter-observer variability was evaluated and the standard tumour area (STA) for each dermoscopy image was defined. Manual extractions by 10 non-medical individuals and by two computer-based methods were evaluated with STA-based assessment criteria: precision and recall. Our new computer-based method introduced the region-growing approach in order to yield results close to those obtained by dermatologists. The effectiveness of our extraction method with regard to diagnostic accuracy was evaluated. Two linear classifiers were built using the results of conventional and new computer-based tumour area extraction methods. The final diagnostic accuracy was evaluated by drawing the receiver operating curve (ROC) of each classifier, and the area under each ROC was evaluated. The standard deviations of the tumour area extracted by five dermatologists and 10 non-medical individuals were 8.9% and 10.7%, respectively. After assessment of the extraction results by dermatologists, the STA was defined as the area that was selected by more than two dermatologists. Dermatologists selected the melanoma area with statistically smaller divergence than that of Clark naevus or Reed naevus (P = 0.05). By contrast, non-medical individuals did not show this difference. Our new computer-based extraction algorithm showed superior performance (precision, 94.1%; recall, 95.3%) to the conventional thresholding method (precision, 99.5%; recall, 87.6%). These results indicate that our new algorithm extracted a tumour area close to that obtained by dermatologists and, in particular, the border part of the tumour was adequately extracted. With this refinement, the area under the ROC increased from 0.795 to 0.875 and the diagnostic accuracy showed an increase of approximately 20% in specificity when the sensitivity was 80%. It can be concluded that our computer-based tumour extraction algorithm extracted almost the same area as that obtained by dermatologists and provided improved computer-based diagnostic accuracy.

Prognosticators of melanoma, the melanoma report, and the sentinel lymph node

Since the 1960s, the clinical characteristics of melanoma, its histopathology and its biological basis have been the subject of intense study at pigmented lesion clinics in North America, Europe, and Australia. More recently, the immense database of the Melanoma Committee of the American Joint Committee on Cancer (AJCC) has been exploited through complex mathematical models to measure the impact of various histologic features of primary melanomas and of sentinel lymph node deposits and to correlate these parameters with patient survival. The wealth of modern information available to pathologists and clinicians has become of vital interest to the prognostication of the individual patient with melanoma. The purpose of this review is to bring to the attention of anatomic pathologists the essential characteristics of the pathology report for primary cutaneous melanoma in the modern era.

Clinical significance of CXCR3 and CXCR4 expression in primary melanoma

Tumor cell migration involved in metastases is a tightly regulated, nonrandom process. Chemokines have been identified as critical molecules guiding cell migration. We performed a prospective study to analyze a possible association between the expression of chemokine receptors CXCR3 and CXCR4 by primary melanoma and clinical outcome. Forty primary melanomas were available for analysis; 57% of the tumors expressed CXCR3 and 35% expressed CXCR4 by melanoma cells. At initial diagnosis, 5 patients had subclinical lymph node involvement and after a median follow-up time of 32 months, 2 additional patients developed regional lymph node metastases and 5 patients developed distant metastases. The expression of CXCR4, but not CXCR3, by melanoma cells in primary lesions was significantly associated with the presence of ulceration, increased tumor thickness, a greater risk of developing regional and distant metastases and a higher mortality rate. Our study underscores the value of CXCR4 expression as a useful marker for predicting outcome in patients with localized melanoma. In addition, our findings support that, among chemokine receptors, CXCR4 might be an appropriate therapeutic target for adjuvant therapy in patients at risk for metastatic disease.

Erfahrungen mit der neuen American Joint Committee on Cancer (AJCC)-Klassifikation des kutanen malignen Melanoms. Experiences with the new American Joint Committee on Cancer (AJCC) classification of cutaneous melanoma

A new AJCC/UICC staging classification of malignant melanoma was published in 2001 and has been in use since then. Compared to the TNM classification used for the previous 15 years, the new classification contains fundamental changes. The classification of the primary tumor is now based on newly defined classes for Breslow's tumor thickness (0 - 1.0 mm; 1.01 - 2.0 mm, 2.01 - 4.0 mm; > 4.0 mm). Histopathologically diagnosed ulceration is the second prognostic factor in primary melanoma and its presence leads to upstaging into the next higher T category. Clark level of invasion is now only relevant for tumors up to 1 mm thick; levels IV and V are also reasons for upstaging. Classification of regional lymph node metastasis distinguishes between microscopic metastasis only as detected with sentinel lymph node biopsy and clinically detectable macroscopic metastasis. Additionally, the number of metastatic nodes and the presence of satellite and in-transit metastasis are prognostic factors for classification of regional lymph node metastasis. In distant metastasis, the kind of organ involvement has a role for classification (only skin and lymph nodes vs. lung vs. other organs) and an elevated LDH value leads to upstaging. A critical analysis of data of the German Central Malignant Melanoma Registry did not confirm the strong role of histopathological ulceration of the primary tumor in all T- and N-stages. Furthermore, there is an inconsistency of the classification as stage IIC displays a significantly worse prognosis as compared to stage IIIA. In spite of these drawbacks the new staging classification should used particularly in clinical trials in order to make data internationally comparable.

Pathologic assessment of melanoma sentinel nodes: a role for molecular analysis using quantitative real-time reverse transcription-PCR for MART-1 and tyrosinase messenger RNA

PURPOSE

Molecular analysis of melanoma sentinel nodes (SN) is sensitive, but poorly specific because metastases cannot be distinguished from benign nevus inclusions (BNI). We investigated whether quantitative reverse transcription-PCR (RT-PCR) detection of MART-1 and tyrosinase mRNAs could improve this specificity and contribute to SN assessment.

EXPERIMENTAL DESIGN

Two hundred twenty SNs from 95 melanoma patients analyzed by extensive immunohistopathology and real-time quantitative RT-PCR.

RESULTS

Using histopathology, SNs and patients were allotted to three diagnostic groups: (a) metastasis positive, (b) BNI positive, and (c) melanocyte-free. Median MART-1 and tyrosinase mRNA levels in SNs were significantly different in patients with metastasis compared with patients with BNIs (P < 0.05) and patients without melanocytic lesions (P < 0.001). However, a "gray-zone" was observed where distinction, based on mRNA levels, could not be made between the three groups. For both genes, the highest mRNA level recorded in each RT-PCR-positive patient was positively correlated with Breslow's tumor thickness. For SNs with metastases, tumor burden was significantly correlated to the mRNA level. Using the presence of a MART-1 RT-PCR signal to detect patients with metastases, a sensitivity of 100% and a negative predictive value of 100% were achieved when extensive immunohistology was used as reference.

CONCLUSIONS

Quantitative RT-PCR MART-1 and tyrosinase mRNA analysis cannot be used alone for SN diagnosis because of its poor specificity for melanoma metastasis. However, in approximately one third of cases without RT-PCR evidence of MART-1 expression, extensive histopathologic SN investigation is not necessary, thus substantially reducing the cost of SN analysis. The level of melanocyte-associated mRNA is associated with both tumor thickness and tumor burden as measured histopathologically, suggesting that this may be of prognostic value.

Overexpression and hyperphosphorylation of retinoblastoma protein in the progression of malignant melanoma

Mutation, absence or abnormal functioning of retinoblastoma protein are fundamental elements of uncontrolled growth in human cancer. In this study, we analyze the expression of retinoblastoma protein and phosphorylated retinoblastoma protein in melanocytic tumors in vivo. Real-time RT-PCR and immunohistochemistry (tissue microarrays and conventional histological sections) reveal that retinoblastoma protein is progressively upregulated in advanced and metastatic malignant melanomas in vivo. However, this increase is paralleled by increased retinoblastoma protein inactivation due to protein phosphorylation. Interestingly, retinoblastoma protein phosphorylation occurs not homogeneously, but with a 'growth zone'-related pattern. In superficial spreading melanomas a subepidermal-lateral maximum of phosphorylated retinoblastoma protein can be frequently observed. Accordingly, nodular vertically invasive melanomas are characterized by a strong staining of phosphorylated retinoblastoma protein in deep-dermal invading protrusions of the tumor. Furthermore, Kaplan-Meier analysis of 13 cases of advanced melanomas with long-time follow-up suggests a significant negative impact of retinoblastoma protein phosphorylation on survival of melanoma patients independent of tumor thickness. We conclude that the evaluation of phosphorylated retinoblastoma protein in melanocytic tumors could become a helpful adjunct in clinicopathological routine.

CEACAM1 enhances invasion and migration of melanocytic and melanoma cells

Expression of the cell adhesion molecule CEACAM1 in melanomas is an independent factor for the risk of metastasis with a predictive value superior to that of tumor thickness. We have previously shown that CEACAM1 co-localizes at the tumor-stroma interface of invading melanoma masses with integrin beta(3) and that these two adhesion molecules interact via the CEACAM1 cytoplasmic domain. To address the functional consequences of CEACAM1 expression, we investigated invasion and migration of melanocytic and melanoma cells that stably express CEACAM1 using two different in vitro systems. Here, we demonstrate that CEACAM1 expression markedly enhances cell invasion and migration. The enhanced invasion and migration of CEACAM1-transfected cells was dependent on the presence of Tyr-488 within the full-length cytoplasmic CEACAM1 domain. Treatment with anti-CEACAM monoclonal antibodies blocked CEACAM1-enhanced cell invasion and cell migration in a dose-dependent manner. Furthermore, the enhanced invasion and migration of CEACAM1-transfected melanoma cells was blocked by integrin-antagonizing RGD peptides. Expression of integrin beta(3) induces the up-regulation of CEACAM1 in melanocytic MEL6 cells. These results strengthen the view that CEACAM1 and alpha(v)beta(3) integrin are functionally interconnected with respect to the invasive growth of melanomas.

Impact of Ulceration in Stages I to III Cutaneous Melanoma As Staged by the American Joint Committee on Cancer Staging System: An Analysis of the German Central Malignant Melanoma Registry

Purpose

In 2001, the new American Joint Committee on Cancer classification of cutaneous melanoma (CM) introduced ulceration of the primary melanoma as a new key parameter being represented in respective subcategories of the tumor (T) classification. The present study was performed to validate the prognostic significance of ulceration in relation to T thickness and clinical stages of CM (stages I to III).

Patients and Methods

Patients (N = 15,158) with incident invasive primary nonmetastatic CM and follow-up data recorded between 1976 and 2000 by the German Central Malignant Melanoma Registry were investigated using survival analysis to evaluate prognostic factors such as T thickness, level of invasion, body site, histologic subtype, ulceration, regression, age, and sex.

Results

Comparisons of survival probabilities according to the Kaplan-Meier method between ulcerated and nonulcerated CM were not statistically significant for subgroups with T thickness ≤ 1 mm and more than 4.00 mm (P = .2601 and P = .0699, respectively) but were significant for T thickness of 1.01 to 2.00 mm and 2.01 to 4.00 mm (P < .0001 for both). This result was confirmed in the multivariate analysis. For stage III CM, the impact of ulceration on overall survival was statistically significant in the bivariate Cox model (P = .0111) but not in the multivariate Cox model (P = .0522).

Conclusion

Whereas ulceration seems to have a negative impact on the prognosis of patients with stages T2 and T3, a potential influence for patients with stages T1 and T4 could not be established. If factors of the primary CM were to be taken into consideration to judge prognosis of stage III CM, T thickness but not ulceration should be the focus.

Indications for lymphatic mapping and sentinel lymphadenectomy in patients with thin melanoma (Breslow thickness < or =1.0 mm)

BACKGROUND

Patients with thin (Breslow thickness < or =1.0 mm) melanoma have a good prognosis (5-year survival >90%). Consequently, the added benefit of lymphatic mapping and sentinel lymphadenectomy (LM/SL) in these patients is controversial. We hypothesize that LM/SL with a focused examination of the sentinel node (SN) will detect a significant number of SN metastases in patients with thin melanoma and that certain clinical or histopathologic factors may serve as predictors of SN tumor involvement.

METHODS

Over 6 years, 349 patients with melanoma underwent LM/SL and were prospectively entered into an institutional review board (IRB)-approved database. LM/SL was performed with a combined radiotracer and blue dye technique. SNs were serially sectioned, and each section was examined by a dermatopathologist at multiple levels with hematoxylin and eosin as well as immunohistochemical stains.

RESULTS

One hundred forty-six patients (42%) had a melanoma with Breslow thickness < or =1.0 mm; six (4%) of these 146 patients had a tumor-involved SN. On multivariate analysis, none of the clinical or histopathologic factors examined were significantly associated with SN tumor involvement in patients with thin melanoma. Completion lymphadenectomy was performed on all patients with a tumor-involved SN. None of the patients had non-SN tumor involvement.

CONCLUSIONS

The incidence of SN tumor involvement in patients with thin melanoma is considerable. Although we were unable to identify predictors of SN tumor involvement in patients with thin melanoma, efforts to identify predictors of SN tumor involvement should continue. Until better predictors are identified, we continue to advocate offering LM/SL to patients with thin melanomas who demonstrate clinical or histopathologic characteristics that have historically been associated with an increased risk of recurrence and mortality.

Prognostic factors of thin cutaneous melanoma: an analysis of the central malignant melanoma registry of the german dermatological society

PURPOSE

The increasing number of thin cutaneous melanomas (CM) with tumor thickness up to 1 mm demands a detailed analysis of prognostic factors for the classification and grading of these tumors. The aim of the present study was to identify prognostic factors in thin CM.

PATIENTS AND METHODS

A series of 12,728 patients with thin incident primary invasive CM and follow-up data recorded between 1976 and 2000 by the German-based Central Malignant Melanoma Registry was analyzed using the multivariate Cox proportional hazard model to evaluate prognostic factors, and classification and regression trees analysis (CART) to define prognostic groups.

RESULTS

Multivariate analysis found tumor thickness, sex, age, body site, and histopathologic subtype to be significant prognostic factors of thin CM. Ulceration and regression did not affect prognosis significantly. Prognostic classification based on the results of CART analysis resulted in three groups defined by tumor thickness, age, and sex. Ten-year survival rates of these groups varied between 91.8% and 98.1%, with improved classification as compared with subgroups by tumor thickness alone.

CONCLUSION

Classification by tumor thickness identified prognostic subgroups with highest significance in thin CM, and the classification was improved by the introduction of age and sex. However, neither ulceration nor the level of invasion included in the new American Joint Committee on Cancer TNM system classification, revealed statistical significance as prognostic factors in thin CM.

The new staging system for cutaneous melanoma in the era of lymphatic mapping

In 2002, the American Joint Committee on Cancer (AJCC) revised the staging system for cutaneous melanoma on the basis of a survival analysis of important melanoma prognostic factors. Features of the revised system include new strata for primary tumor thickness, incorporation of primary tumor ulceration as an important staging criterion in both the tumor (T) and node (N) classifications, revision of the N classification to reflect the prognostic significance of regional nodal tumor burden, and new categories for distant metastatic disease. These changes reflect evolving insight into melanoma arising from the results of numerous clinical investigations and database analyses. One of the most important recent changes in melanoma care is the establishment of lymphatic mapping and sentinel lymph node (SLN) biopsy as a highly accurate and minimally morbid technique for pathologic regional nodal staging. In this article, the salient features of the revised melanoma staging system are examined, with specific attention paid to its use in this era of lymphatic mapping and SLN biopsy.

Linear discriminant analysis of dermoscopic parameters for the differentiation of early melanomas from Clark naevi

As a first step to develop a screening system for pigmented skin lesions, we performed digital discriminant analyses between early melanomas and Clark naevi. A total of 59 cases of melanoma, including 23 melanoma in situ and 36 thin invasive melanomas (Breslow thickness < or =0.75 mm), and 188 clinically equivocal, histopathologically diagnosed Clark naevi were used in our study. After calculating 62 mathematical variables related to the colour, texture, asymmetry and circularity based on the dermoscopic findings of the pigmented skin lesions, we performed multivariate stepwise discriminant analysis using these variables to differentiate melanomas from naevi. The sensitivities and specificities of our model were 94.4 and 98.4%, respectively, for discriminating between melanomas (Breslow thickness < or =0.75 mm) and Clark naevi, and 73.9 and 85.6%, respectively, for discriminating between melanoma in situ and Clark naevi. Our algorithm accurately discriminated invasive melanomas from Clark naevi, but not melanomas in situ from Clark naevi.

Sentinel lymph node biopsy in melanoma patients: the medical oncologist's perspective

With the advent of sentinel node (sN) biopsy in melanoma patients, elective lymph node dissection (ELND) can be considered an exceeded procedure. Regardless of the possible therapeutic benefits, sN biopsy efficiently predicts prognosis avoiding the morbidity rate of ELND. The importance of the sN is underlined by multivariate analyses, which show that the sN status represents the most important prognostic factor influencing disease-free and distant disease-free survival in patients with stage I and II melanoma. Moreover, sN biopsy provides a minimally invasive method for identifying those patients with subclinical nodal metastasis who actually have stage III disease, with a very high risk of occult distant metastases and who may benefit by adjuvant therapy.

New TNM melanoma staging system: linking biology and natural history to clinical outcomes

The American Joint Committee on Cancer (AJCC) implemented major revisions of the melanoma TNM and stage grouping criteria in the recently published 6th edition of the Staging Manual. The new staging system better reflects independent prognostic factors that are used in clinical trials and in reporting the outcomes of various melanoma treatment modalities. Major revisions include: 1) melanoma thickness and ulceration but not level of invasion to be used in the T classification, 2) the number of metastatic lymph nodes rather than their gross dimensions and the delineation of microscopic vs. macroscopic nodal metastases to be used in the N classification, 3) the site of distant metastases and the presence of elevated serum lactic dehydrogenase (LDH) to be used in the M classification, 4) an upstaging of all patients with Stage I, II, and III disease when a primary melanoma is ulcerated, 5) a merging of satellite metastases around a primary melanoma and in transit metastases into a single staging entity that is grouped into Stage III disease, and 6) a new convention for defining clinical and pathological staging so as to take into account the new staging information gained from intraoperative lymphatic mapping and sentinel node biopsy.

Validity of an unsupervised self-administered questionnaire for self-assessment of melanoma risk

Mass screening for cutaneous melanoma is impracticable because of its low yield and high costs. The validity of self-selection of high-risk individuals through self-assessment of melanoma risk factors is not known. The aim of this study was to assess the validity of an unsupervised self-administered questionnaire for the self-assessment of melanoma risk. In a case-control study, melanoma cases (n = 202) and controls (n = 202) matched for age and gender filled in a questionnaire about melanoma risk factors. After filling in the questionnaire, all participants were interviewed and examined by a dermatologist in order to compare self-assessment with physician-assessment. The number of naevi, skin phototype and ultraviolet damage to the skin were identified as independent risk factors for melanoma on both self-assessment and physician-assessment. Receiver operating characteristics analysis showed no statistically significant difference between the accuracy of the self-assessment-based model and the model based on physician-assessment. While excluding 90% of the controls, the self-assessment-based high-risk group included 39% (95% confidence interval 31-48%) of the melanoma patients and the physician-assessment-based high-risk group included 42% (95% confidence interval 33-52%) of the melanoma patients. In conclusion, an unsupervised self-administered questionnaire is, to some extent, useful for the identification of individuals at high risk for melanoma. The moderate accuracy of self-assessment and physician-assessment to identify individuals at high risk for melanoma is a limitation for the practicability of targeted melanoma screening in general.

Prognosis for patients with thin cutaneous melanoma: long-term survival data from New South Wales Central Cancer Registry and the Sydney Melanoma Unit

BACKGROUND

Estimates of long-term survival for patients with thin (< or = 1 mm) primary cutaneous melanomas vary widely. Two separate methods were used to study the survival of patients with melanoma from New South Wales (NSW), Australia, and from the Sydney Melanoma Unit (SMU).

METHODS

The NSW Central Cancer Registry (NSWCCR) provided data on all patients who were diagnosed with cutaneous melanomas that measured < or = 1 mm thick between 1983 and 1998, inclusive. Patients with metastases at the time of diagnosis were not included, leaving 18,088 patients for analysis. The SMU data base was analyzed to extract data for all patients with thin melanomas who met the same criteria from 1979 to 1998, inclusive. All patients who had their primary tumors treated definitively elsewhere were excluded, leaving 2746 patients for analysis. Ten-year Kaplan-Meier survival rates were calculated, and significant differences were determined using log-rank analysis. Prognostic factors were evaluated with Cox proportional hazards analysis.

RESULTS

The NSWCCR analysis revealed a 10-year survival rate of 96.4%. The 10-year survival rate for patients at SMU was 92.7%. Among the patients at SMU who died, the median time to recurrence was 49.8 months, and the median time to death was 65.9 months. The 10-year survival for patients at SMU who had lesions that measured < or = 0.75 mm was 96.9% compared with 84.3% for patients who had lesions that measured 0.76-1.0 mm. For patients who had ulcerated melanomas measuring < or = 1 mm thick, the 10-year survival rate was 83%, compared with 92.3% for patients who had nonulcerated melanomas.

CONCLUSIONS

The results of the current study confirmed the excellent survival rate for patients with thin melanomas. Higher-risk subsets of patients who may warrant consideration for aggressive investigation and treatment are identifiable.