Prognostic value of morphometric features and the callender classification in uveal melanomas

The prognostic implication of visual acuity at the time of uveal melanoma diagnosis

BACKGROUND

Visual outcomes after primary tumour treatment of uveal melanoma (UM) have been investigated repeatedly. This study evaluates the correlation between best-corrected visual acuity (BCVA) before treatment with clinicopathological factors and patient survival.

SUBJECTS/METHODS

Pre-treatment BCVA was examined in relation to tumour dimensions and location, and survival in a retrospective cohort of 1809 patients who underwent plaque brachytherapy. BCVA was also correlated to tumour histological factors in a second cohort of 137 enucleated eyes.

RESULTS

The mean BCVA of the tumour eye prior to plaque brachytherapy was LogMAR 0.42 (SD 0.46). Patients with low BCVA (LogMAR ≥ 1.00) did not differ in age (p = 0.19) and had similar frequency of ciliary body involvement (p = 0.99) but had tumours with greater apical thickness (p < 0.0001), greater diameter (p < 0.0001) and shorter distance to the optic disc and fovea (p < 0.0001). There were no significant relations between low BCVA and any of 13 examined tumour histological factors at a Bonferroni-corrected significance level (p > 0.004). Patients with low BCVA had greater incidence of UM-related mortality in competing risk analysis (p = 0.0019) and shorter overall survival (p < 0.0001). Low BCVA was also associated with increased hazard ratio (HR) for UM-related mortality in univariate analysis (HR 1.5, 95% confidence interval 1.2 to 1.9), but not in multivariate analysis with tumour size and location as covariates.

CONCLUSIONS

UM patients with low BCVA before primary tumour treatment have a worse prognosis, likely related to increased tumour dimensions. Future studies should examine the prognostic significance of BCVA in relation to macula-involving retinal detachment and genetic factors.

Choroidal biopsies; a review and optimised approach

The majority of choroidal tumours are diagnosed accurately with clinical examination and the additional data obtained from non-invasive imaging techniques. Choroidal biopsies may be undertaken for diagnostic clarity in cases such as small melanocytic or indeterminate lesions, identifying the primary tumour in the case of choroidal metastases or the subclassification of rarer conditions such as uveal lymphoma. There is however an increasing use of biopsy techniques for prognostication in uveal melanoma. This review explores the main indications and surgical techniques for tumour acquisition, and the optimised approach utilised by the current authors to improve successful yield for histological and genetic analysis.

Digital morphometry of tumor nuclei correlates to BAP-1 status, monosomy 3, gene expression class and survival in uveal melanoma

Cytologic features such as the shape and size of tumor cells can predict metastatic death in uveal melanoma and other cancers but suffer from poor reproducibility. In this study, we investigate the interobserver concordance of digital morphometry, and correlate the results with BRCA associated protein-1 (BAP-1) expression and BAP-1 gene mutation status, monosomy 3, gene expression classifications and patient survival in uveal melanoma. The average number of cells analyzed in each of 107 tumors, was 1957 (SD 349). Mean time consumption was less than 2.5 min per tumor. Identical morphometric classification was obtained for ≥85% of tumors in all twelve evaluated morphometric variables (κ 0.70-0.93). The mean nucleus area, nucleus perimeter, nucleus max caliper and nucleus to cell area ratio were significantly greater in tumors with low BAP-1 expression and gene expression class 2. Patients had significantly shorter survival if their tumors had low BAP-1 (Log-Rank p = 0.002), gene expression class 2 (p = 0.004), long nucleus perimeters (p = 0.031), long nucleus max calipers (p = 0.029) and high mean nucleus to cell area ratios (p = 0.041) as defined in a training cohort and then tested in a validation cohort. Long nucleus perimeters and long nucleus max calipers correlated with monosomy 3 (Pearson Chi-Square p = 0.006 and p = 0.009, respectively). Long nucleus perimeters also correlated with BAP-1 mutation (p = 0.017). We conclude that digital morphometry can be fast and highly reproducible, that for the first time, morphometry parameters can be objectively quantitated in thousands of cells at a time in sub-μm resolutions, and that variables describing the shape and size tumor nuclei correlate to BAP-1 status, monosomy 3, gene expression class as well as patient survival.

Clinical and histopathological features of choroidal melanoma-related enucleated eyes in a Spanish tertiary hospital

OBJECTIVE

To study clinical and pathological variables leading to a poor prognosis in a sample of uveal malignant melanoma patients who required eyeball enucleation as final treatment approach. All patients were seen and treated in the same public tertiary hospital in Madrid (Spain) within a 6-year time-period.

MATERIALS AND METHODS

Longitudinal observational retrospective study. The presence of clinical and pathologic factors known to be linked to poor prognosis, as well as other features, was assessed in 30 malignant melanoma: 20 de novo-enucleated malignant melanoma eyes (group A), and 10 in eyes that received radiotherapy prior to enucleation (group B). The diagnostic reliability of magnetic resonance imaging was assessed by comparing it with the histology results (gold standard) as a means to detect scleral and extra-scleral extension.

RESULTS

Tumour size, Bruch's membrane rupture, scleral infiltration, and distance to the optic nerve were the most decisive factors for a poor prognosis in the study sample. In 93% of cases the condition was under control, with a 6% incidence rate of metastatic spread and a 100% rate of overall survival for a mean follow-up period of 3±1.5 (range 1.2-6) years. In the study population, the sensitivity of the magnetic resonance imaging to detect scleral infiltration was 27%, which increased to 100% for identifying extra-scleral involvement.

CONCLUSIONS

The analyses of the clinical and pathological data collected within the framework of this study justify enucleation as the treatment of choice for the patients of this study. Magnetic resonance imaging was not found to be an optimum screening method to detect scleral infiltration in this study sample.

Clinical, pathologic, and imaging features and biological markers of uveal melanoma

Uveal melanoma has unique clinical and pathologic features including virtually exclusive metastasis to the liver in high-risk cases. In this chapter, the clinical findings in uveal melanoma and diagnostic methods including imaging tests and serum markers are described. Additionally, the histopathologic features including the modified Callender classification and immunohistochemical findings of uveal melanoma are described.

Sufficiency of FNAB aspirates of posterior uveal melanoma for cytologic versus GEP classification in 159 patients, and relative prognostic significance of these classifications

Objective

To determine the relative sufficiency of paired aspirates of posterior uveal melanomas obtained by FNAB for cytopathology and GEP, and their prognostic significance for predicting death from metastasis.

Methods

Prospective non-randomized IRB-approved single-center longitudinal clinical study of 159 patients with posterior uveal melanoma sampled by FNAB in at least two tumor sites between 09/2007 and 12/2010. Cases were analyzed with regard to sufficiency of the obtained aspirates for cytopathologic classification and GEP classification. Statistical strength of associations between variables and GEP class was computed using Chi-square test. Cumulative actuarial survival curves of subgroups of these patients based on their cytopathologic versus GEP-assigned categories were computed by the Kaplan–Meier method. The endpoint for this survival analysis was death from metastatic uveal melanoma.

Results

FNAB aspirates were insufficient for cytopathologic classification in 34 of 159 cases (21.9 %). In contrast, FNAB aspirates were insufficient for GEP classification in only one of 159 cases (0.6 %). This difference is statistically significant (P < 0.001). Six of 34 tumors (17.6 %) that yielded an insufficient aspirate for cytopathologic diagnosis were categorized as GEP class 2, while 43 of 125 tumors (34.7 %) that yielded a sufficient aspirate for cytopathologic diagnosis were categorized as GEP class 2. To date, 14 of the 49 patients with a GEP class 2 tumor (28.6 %) but only five of the 109 patients with a GEP class 1 tumor (5.6 %) have developed metastasis. Fifteen of 125 patients (12 %) whose tumors yielded sufficient aspirates for cytopathologic classification but only four of 34 patients (11.8 %) whose tumors yielded insufficient aspirates for cytopathologic classification developed metastasis. The median post-biopsy follow-up time for surviving patients in this series was 32.5 months. Cumulative actuarial 5-year probability of death from metastasis 14.1 % for those with an insufficient aspirate for cytopathologic classification versus 22.4 % for those with a sufficient aspirate for cytopathologic classification (log rank P = 0.68). In contrast, the cumulative actuarial 5-year probability of metastatic death was 8.0 % for those with an insufficient/unsatisfactory aspirate for GEP classification or GEP class 1 tumor, versus 45.0 % for those with a GEP class 2 tumor (log rank P = 0.005).

Conclusion

This study confirmed that GEP classification of posterior uveal melanoma cells obtained by FNAB is feasible in almost all cases, including most in which FNAB yields an insufficient aspirate for cytodiagnosis. The study also confirmed that GEP classification is substantially better than cytologic classification for predicting subsequent metastasis and metastatic death.

Melanoma associated spongiform scleropathy: characterization, biochemical and immunohistochemical studies

SUMMARY

Melanoma associated spongiform scleropathy (MASS) is a non-inflammatory scleral change with a spongiotic morphology seen in association with uveal melanoma. MASS is seen as whitish spindle shaped areas within the sclera that is adjacent to and in contact with a choroidal or ciliary body melanoma. This change can be seen as small scattered lesions in the inner scleral layers or as extensive areas along the whole extent of contact between the tumour and the sclera and involves most of the scleral thickness. MASS changes of different grades of severity were seen in 38% of 363 melanoma eyes investigated. The presence of MASS showed a statistical correlation with age. A significant high incidence of MASS was found in old age groups. This might due to the fact that MASS needs a longer period of contact between the tumour and the sclera to develop. It is also possible that age-related changes of the extracellular matrix might alter its response to melanoma produced factors leading to the development of MASS. The development of MASS and its severity are influenced by the extent of contact between the tumour and the sclera. This is supported by the significant statistical relation between the largest basal diameter of the tumours and the severity of MASS. Statistical correlation was found between MASS and scleral and extrascleral tumour extension. More than 90% of 82 specimens that showed tumour extension were associated with MASS. A biochemical analysis of scleral samples taken from areas with severe MASS showed a significant reduction of the main amino acids of collagen type I, which is the main scleral collagen. The amounts of total scleral proteins were significantly reduced. This scleral protein reduction is associated with an increase in glycosaminoglycans. These findings indicate a collagen degradation process. Immunohistochemical studies were performed to investigate the expression of matrix metalloproteinases (MMPs). In situ hybridization showed a significantly more frequent and more intense expression of MMP-2 by scleral fibroblasts in areas with MASS compared with areas without MASS. This was also seen by immunohistochemical staining. Similar high frequency and intense expression of MMP-2 were seen in tumour infiltrating macrophages. The results of biochemical and immunohistochemical studies indicate a collagen degradation process. This degradation may be the result of the proteolytic enzyme MMP-2 expressed by scleral fibroblasts under the effect of tumour humeral factors and/or tumour infiltrating macrophages. This scleral degradation results in fragmentation of the scleral collagen fibrils. This along with the accumulation of water in the sclera, as a result of the increase in the production of glycosaminoglycans, results in increase of scleral thickness in MASS areas and forms the histopathological picture of MASS. The scleral degradation may facilitate tumour invasion and may explain the statistical relation between MASS and scleral tumour invasion. MASS was found in a few of the eyes that had received pre-enucleation radiation. The possible explanation is that radiation might cause destruction of scleral fibroblasts reducing their ability to produce MMP-2, thus decreasing the development of MASS. No relation between MASS and survival was found. This is probably explained by the fact that the main cause of death due to uveal melanoma is distant metastasis. MASS changes are found to be associated with local tumour invasion but not statistically correlated to survival.

Visualization of circulating melanoma cells in peripheral blood of patients with primary uveal melanoma

PURPOSE

In patients with uveal melanoma, tumor cell dissemination and subsequent formation of metastases are confined mainly to the hematogenous route. Here, we sought to isolate circulating melanoma cells in peripheral blood of patients with primary uveal melanoma and clinically localized disease.

EXPERIMENTAL DESIGN

Blood samples from 52 patients with clinically localized uveal melanoma and from 20 control individuals were prospectively collected before therapy of the primary tumor. Tumor cells expressing the melanoma-associated chondroitin sulfate proteoglycan were enriched by immunomagnetic cell sorting and visualized by immunocytologic staining. Results were compared with clinical data at presentation.

RESULTS

In 10 of 52 patients [19%; 95% confidence interval (95% CI), 10-33%], between 1 and 5 circulating melanoma cells were detected in 50 mL peripheral blood. No melanoma-associated chondroitin sulfate proteoglycan-positive cells were detected in any of the 20 controls examined. The presence of tumor cells in peripheral blood was associated with ciliary body invasion [odds ratio (OR), 20.0; 95% CI, 3.0-131.7], advanced local tumor stage (OR, 6.7; 95% CI, 1.8-25.4), and anterior tumor localization (OR, 4.0; 95% CI, 1.2-12.7), all established factors for uveal melanoma progression.

CONCLUSIONS

Immunomagnetic enrichment enables detection of intact melanoma cells in peripheral blood of patients with clinically localized ocular disease. Visualization and capturing of these cells provide a unique tool for characterizing potentially metastasizing tumor cells from a primary melanoma at an early stage of the disease.

Optic nerve invasion of uveal melanoma

The aim of the study was to identify the histopathological characteristics associated with the invasion of the optic nerve of uveal melanoma and to evaluate the association between invasion of the optic nerve and survival. In order to achieve this, all uveal melanomas with optic nerve invasion in Denmark between 1942 and 2001 were reviewed (n=157). Histopathological characteristics and depth of optic nerve invasion were recorded. The material was compared with a control material from the same period consisting of 85 cases randomly drawn from all choroidal/ciliary body melanomas without optic nerve invasion. Prelaminar/laminar optic nerve invasion was in multivariate analysis associated with focal retinal invasion, neovascularization of the chamber angle, and scleral invasion. Postlaminar invasion was further associated with non-spindle cell type and rupture of the inner limiting membrane of the retina. The optic nerve was invaded in four different ways: 1) by tumor extension from the neuroretina through the lamina cribrosa; 2) by direct extension into the optic nerve head between Bruch's membrane and the border tissue of Elschnig; 3) by direct invasion through the border tissue of Elschnig; and 4) in one case a tumor spread along the inner limiting membrane to the optic nerve through the lamina cribrosa. Invasion of the optic nerve had no impact on all-cause mortality or melanoma-related mortality in multivariate analyses. The majority of melanomas invading the optic nerve are large juxtapapillary tumors invading the optic nerve because of simple proximity to the nerve. A neurotropic subtype invades the optic nerve and retina in a diffuse fashion unrelated to tumor size or location.

Prognostic factors for survival after enucleation for choroidal and ciliary body melanomas

PURPOSE

To evaluate prognostic factors for the survival of patients treated by enucleation for choroidal and ciliary body melanomas.

METHODS

The study included 293 consecutive patients (147 men and 146 women) treated by enucleation for a choroidal or ciliary body melanoma during the period 1955-2000. The median age at treatment was 61 years (range 26-88 years). Clinical and histopathological findings, vital status at October 1st, 2002, and cause of death were registered. Prognostic factors for survival were evaluated by univariate and multivariate Cox proportional hazards analysis and by Kaplan-Meier survival analysis.

RESULTS

Follow-up was complete. The median follow-up time was 6.2 years (range 21 days to 43.4 years) and the median potential follow-up time was 25.7 years (range 1.9-47.7 years). In multivariate Cox proportional hazards analysis an increased risk of melanoma-related death was found for largest basal diameter (n = 264, p < 0.001, mortality rate ratio (RR) = 1.09 for continuous parameter in mm), anterior tumour margin at the iris/ciliary body versus choroid (p < 0.001, RR = 2.22), and non-spindle cell type versus spindle cell (p = 0.047, RR = 1.45). An increased risk of death from all causes was found for men versus women (n = 266, p = 0.02, RR = 1.41), high age (p < 0.001, RR = 1.41 for continuous parameter in 10-year age groups), largest basal diameter (p < 0.001, RR = 1.07), anterior tumour margin at the iris/ciliary body (p = 0.02, RR = 1.52), and non-spindle cell type (p = 0.04, RR = 1.34).

CONCLUSION

The risk of melanoma-related death after enucleation for a choroidal or ciliary body melanoma was high for tumours with large basal diameter, of non-spindle cell type and anterior location. Additional risk factors for death from all causes were male sex and high age.

Primary mucosal melanoma of the head and neck: a proposal for microstaging localized, Stage I (lymph node-negative) tumors

BACKGROUND

The current study was conducted to identify histologic predictors of survival in patients with localized, lymph node-negative (Stage I, N0M0) primary mucosal melanomas of the head and neck (HNMM).

METHODS

The histology of 39 sinonasal, 20 oral, 1 pharyngeal, and 1 laryngeal Stage I HNMM was reviewed by 2 pathologists without knowledge of patient outcome. The invasion was evaluated as Level I: melanoma in situ (without invasion or with microinvasion only); Level II: invasion into the lamina propria only; and Level III: invasion into deep tissue (e.g., skeletal muscle, bone, or cartilage). The tumor architecture was defined as pseudopapillary when tumor cells clustered around blood vessels resembling papillae and sarcomatoid when they resembled high-grade pleomorphic sarcoma. Survival analysis was performed with Kaplan-Meier survival curves using disease-specific survival (DSS) as the endpoint.

RESULTS

The 5-year DSS rate was 43% (median, 41.5 months). The median survival was found to decrease significantly with increasing level of invasion: Level I (n = 4): 138 months; Level II (n = 29): 69 months; and Level III (n = 28): 17 months (P = 0.003). The presence of pseudopapillary and sarcomatoid architecture (n = 20) and undifferentiated cells (n = 16) were found to be associated with a significantly poor DSS (P < 0.05). However, on multivariate analysis, only the level of invasion remained an independent predictor of survival (P = 0.03). Tumor thickness, vascular invasion, and necrosis were found to have no significant influence on survival.

CONCLUSIONS

Microstaging according to invasion into three tissue compartments was found to be a significant and independent predictor of poor survival in patients with localized, lymph node-negative, Stage I HNMM. The presence of sarcomatoid and pseudopapillary architecture and undifferentiated cells also appear to be associated with significantly poor DSS.

Prognostic factors for malignant melanoma of the squamous mucosa of the head and neck

Primary malignant melanomas of the squamous mucosa of the head and neck are rare. To learn more about the prognostic significance of various histologic parameters we examined the pathologic features of squamous mucosa from 40 patients seen at a single institution and correlated them with clinical outcome. Follow-up information was available on 37 patients. Thirty-five were treated with surgical resection and two were treated with radiotherapy. Twenty-six were dead at follow-up. Twenty-one of them died of disease. The interval between diagnosis and death ranged from 1 month to 16.5 years (median survival, 2.4 years). Eleven patients were alive at 4 months to 19.5 years after the diagnosis: six of them with disease and five of them free of disease (mean follow-up, 3.5 years). Predictors of poor survival by univariate analysis were the presence of vascular invasion (overall survival, p = 0.007; disease-specific survival, p = 0.01), a polymorphous tumor cell population (overall survival, p = 0.007; disease-specific survival, p = 0.008), and necrosis (overall survival, p = 0.007; disease-specific survival, p = 0.056). However, because these three parameters were associated with each other, none of them remained of independent predictive value for outcome by multivariate analysis. No prognostic significance was found for tumor thickness, level of invasion, ulceration, mitotic index, or nerve/nerve sheath involvement. Thus, the histologic parameters relevant for the prognosis of squamous mucosa differ significantly from those of cutaneous melanomas.

Cytomorphometric parameters and the metastatic potential of cutaneous and uveal melanoma: a comparison with prognostic factors

The Mean of the Ten Largest Nuclei (MTLN1) is one of the most important prognostic factors in uveal malignant melanoma. This study was performed to investigate the applicability of nuclear and nucleolar measurements as a prognostic factor for cutaneous melanoma. A routine light microscope (Carl Zeiss: Axiophot EL-Einnsatz; #451888) at 640 times magnification with a Micrometer Eye Piece (Carl Zeiss: #444034) was used to evaluate the correlation of MTLN1 and Mean of Ten Largest Nuclei (MTLN) with the occurrence of metastasis in 58 primary cutaneous melanoma. For uveal melanoma, cytologic classification was used for comparison. Prognostic value was determined by univariate and multivariate linear regression analysis. MTLN1 was the only significant factor for uveal melanoma (p = 0.05). For cutaneous melanoma, all factors were significantly associated with disease progression. MTLN1 was the only one to remain significant (p + 0.027) in multivariate linear regression analysis. Nuclear and nucleolar morphometry are significant prognostic factors for uveal and cutaneous melanoma.

Histopathologic characteristics of uveal melanomas in eyes enucleated from the Collaborative Ocular Melanoma Study. COMS report no. 6

PURPOSE

To describe the principal histopathologic findings in a series of 1,527 globes with uveal melanoma and the relationship of these findings to each other.

METHODS

All eyes enucleated in the Collaborative Ocular Melanoma Study (COMS) were examined independently by three ophthalmic pathologists and the findings recorded on a data form. A composite of findings was obtained after adjudication.

RESULTS

The diagnosis was choroidal melanoma in 1,527 (99.7%) of 1,532 cases examined. Misdiagnoses were metastatic adenocarcinoma (four) and hemangioma (one). Spindle cell (9.0%), mixed cell (86.0%), and epithelioid cell (5.0%) types were observed. Medium tumors were located more posteriorly than large tumors. Considerable local invasion was seen: rupture of Bruch's membrane (87.7%), invasion of the retina (49.1%), tumor cells in the vitreous (25.2%), vortex vein invasion (8.9%), invasion of tumor vessels by tumor cells (13.8%), and invasion into emissary canals (55.0%). Overall, 81.1% demonstrated local invasion, excluding rupture of Bruch's membrane. Scleral invasion was present in 55.7% of eyes, and extrascleral extension was present in 8.2%. Mitotic activity was significantly reduced in eyes that had received preenucleation radiation treatment (P < .001). The number of macrophages in the tumor increased with increased pigmentation (P < .001) and increased necrosis (P < .01).

CONCLUSION

The accuracy of diagnosis in the COMS is high, with histopathologic confirmation of the diagnosis at 99.7%. Extensive local invasion of the tumor was seen. Preenucleation irradiation significantly reduced the number of mitotic figures. An association was found regarding the presence of macrophages, the level of pigmentation, and degree of necrosis.

The microcirculation of choroidal and ciliary body melanomas

The microcirculation of ciliary body and choroidal melanomas is remodelled into patterns. The presence of microvascular networks, composed of back-to-back loops that encircle microdomains of tumour, and parallel vessels with cross-linking, are associated with death from metastatic melanoma. The formation of these complex vascular patterns may result from reciprocal interactions between the tumour cell and the extracellular matrix, and pattern formation may reflect an invasive tumour cell phenotype. Ciliary body and choroidal melanomas are among the few forms of cancer treated before a pathologist assigns a grade to indicate whether tumour is likely to follow a benign or aggressive course. There is evidence to suggest that prognostically significant microcirculatory patterns may be detectable by non-invasive imaging techniques that may provide a substitute for biopsy to guide the clinical management of patients with these sight- and life-threatening tumours.

Uveal melanoma. Comparison of the prognostic value of fibrovascular loops, mean of the ten largest nucleoli, cell type, and tumor size

PURPOSE

This study was performed to determine the prognostic significance of the presence of loops defined as periodic acid-Schiff-positive fibrovascular septa that completely surround lobules of tumor cells in cases of uveal melanoma.

METHODS

The presence of loops was evaluated using an ordinary light microscope and routinely stained periodic acid-Schiff and hematoxylin sections from 496 posterior uveal melanomas without knowledge of the follow-up data on the patient.

RESULTS

At 15 years, survival decreased from 67.5% to 33.8% when complete loops were present. Univariate Cox regression analysis indicated that the presence of loops was an indicator of poor outcome, and was better than age but not as good as the mean diameter of the largest nucleoli, cell type, or tumor size.

CONCLUSIONS

The presence of loops, as evaluated in this study, was not as strong an indicator of poor outcome as were loops assessed in a previous study of 234 cases from another laboratory. The authors suspect this difference may be due to their only using routinely stained sections without a green filter, as was used in previously reported studies. The authors description of loops does not require any special equipment and gives sufficiently useful results to justify its inclusion by the pathologist in reports of such specimens. A description of vascular loops should be added to the use of the modified Callender cell type, tumor dimensions, mitotic count, extraocular extension, and lymphocytic infiltration in the final pathologic report.