Malignant melanoma: some aspects of pathology and prognosis

Prognosis of patients with transected melanomas

BACKGROUND

The management of melanoma is directly related to Breslow's depth. Biopsying melanomas in a fashion that transects the deep margin precludes an accurate measurement of the true depth.

OBJECTIVE

To examine the prognosis of melanomas transected along the deep margins, as well as cases where no residual melanoma was seen on re-excision after transection.

METHODS

Records from a cohort of patients at one institution were examined from 1996 through 2007. Patients were considered to have "transected" melanomas if tumor cells were present on the deep margin of the biopsy. Overall survival was determined.

RESULTS

Seven hundred fourteen patients were examined. 171 (24%) of all melanomas were transected. 101(59%) of those lacked tumor cells on re-excision. Patients with transected melanomas were older (OR = 1.03, p < .001), and had higher Breslow's depths (OR = 1.21, p < .001) than those without transected tumors. Those with no residual melanoma after transection were younger (OR = 0.98, p = .010) and more likely to have no lymph node involvement (OR = 2.23, p = .037). Neither transection (p = .760), nor lack of residual melanoma on re-excision after transection (p = .793) influenced survival.

CONCLUSION

A high number of melanomas are transected at diagnosis, many of which lack visible tumor. The original Breslow's depth of transected melanomas without residual tumor on re-excision accurately predicts survival and prognosis.

Non-radical diagnostic biopsies do not negatively influence melanoma patient survival

BACKGROUND

In fair-skinned Caucasian populations both the incidence and mortality rates of cutaneous melanoma have been increasing over the past decades. With adjuvant therapies still being under investigation, early detection is the only way to improve melanoma patient survival. The influence of incisional biopsies on melanoma patient survival has been discussed for many years. This study investigates both the influence of diagnostic biopsy type and the presence of residual tumor cells in the re-excision specimen on disease free and overall survival.

METHODS

After (partial) removal of a pigmented skin lesion 471 patients were diagnosed with stage I/II melanoma and underwent re-excision and a sentinel node biopsy. All patients were followed prospectively, mean follow up >5 years. Patients were divided according to their diagnostic biopsy type (wide excision biopsy, narrow excision biopsy, excision biopsy with positive margins and incisional biopsy) and the presence of residual tumor cells in their re-excision specimen. Survival analysis was done using Cox's proportional hazard model adjusted for eight important confounders of melanoma patient survival.

RESULTS

The diagnostic biopsy was wide in 279 patients, narrow in 109 patients, 52 patients underwent an excision biopsy with positive margins and 31 patients an incisional biopsy. In 41 patients residual tumor cells were present in the re-excision specimen. Both the diagnostic biopsy type and the presence of tumor cells in the re-excision specimen did not influence disease free and overall survival of melanoma patients.

CONCLUSIONS

Non-radical diagnostic biopsies do not negatively influence melanoma patient survival.

Clinical investigation of amelanotic malignant melanoma in the oral region

PURPOSE

Amelanotic oral malignant melanoma (AOMM) is a rare tumor that is difficult to diagnose. We studied the clinical and pathologic features of nine cases of this tumor to define diagnostic criteria and estimate prognoses for 2 different types of AOMM.

PATIENTS AND METHODS

Nine patients with 2 different types of primary AOMM were examined between 1970 and 2002. The histopathology of surgical specimens was studied, uncertain diagnoses were supported by immunohistochemical reactions, and electron microscopy and prognoses were reviewed retrospectively.

RESULTS

AOMM without radial growth phase may be particularly difficult to diagnose correctly without immunohistochemical assistance. Tumors consisted of a mixture of polygonal and spindle cells in different ratios in tumors with and without radial growth phase. The life span ranged from 3 months to 6 years 3 months, and all 9 patients died of the tumor. In 7 of the 9 cases, distant metastases were found.

CONCLUSIONS

AOMM without radial growth phase may be misdiagnosed as epulis or squamous cell carcinoma. Questionable lesions, particularly maxillary and palatal lesions, must be biopsied for histopathologic and possibly immunohistochemical examinations followed by rapid treatment. The prognosis of AOMM was poor.

A retrospective observational study of primary cutaneous malignant melanoma patients treated with excision only compared with excision biopsy followed by wider local excision

BACKGROUND

For primary cutaneous malignant melanoma the guidelines recommend an excision biopsy of the suspected lesion followed by wider local excision; the diagnosis can then be confirmed and excision margins planned.

OBJECTIVES

To compare retrospectively the clinicopathological features, surgical margins and survival of patients from the Scottish Melanoma Group database whose tumour was removed by excision only (one-stage) or excision biopsy followed by wider local excision (two-stage) surgery.

METHODS

The Scottish Melanoma Group database records the clinicopathological features, surgical treatment and follow-up information of all patients with malignant melanoma in Scotland. From this 1595 patients were identified over a 19-year interval from 1979 to 1997 with follow-up until the end of December 1999. Overall survival, disease-free survival and recurrence-free interval were examined with univariate and multivariate statistical methods.

RESULTS

The patients in the one-stage excision group (n = 547) were statistically significantly older (P < 0.001), had thicker melanomas (P < 0.001), a higher proportion of lentigo maligna melanomas (P < 0.001), head and neck (P < 0.001), and ulcerated lesions (P < 0.003) compared with the two-stage group (n = 1048). The margins of excision were significantly narrower in the one-stage compared with the two-stage group (P < 1 x 10(-5)). Fifty-two percent of all one-stage excisions were performed with a margin < 1 cm compared with 20% of the two-stage group. The excision margin was more positively correlated with the Breslow thickness for the two-stage over the one-stage group (Spearman rho = 0.38, P < 0.001; and 0.27, P < 0.001, respectively). Overall survival (OS), disease-free survival (DFS), and recurrence-free survival (RF) were all statistically significantly better in the two-stage compared with the one-stage excision group, P < 1 x 10(-5), P < 1 x 10(-5) and P = 0.001, respectively (log rank test). After adjusting for the prognostic factors of age, sex, tumour thickness, site, histology and ulceration, OS, DFS and RF were still significantly better in the two-stage compared with the one-stage group [hazard ratio (HR) 0.75, 95% confidence interval (CI) 0.61-0.92, P = 0.006; HR 0.75, CI 0.62-0.90, P = 0.002; and HR 0.78, CI 0.62-0.99, P = 0.04, respectively].

CONCLUSIONS

This study showed that one-stage excisions were more common in patients with poorer prognostic features and that excision with margins narrower than those suggested by current guidelines was more likely. Patient survival was statistically significantly better with the two-stage procedure, although the reasons for this were unclear.

Oral malignant melanoma: long-term follow up in three patients

Three patients with oral malignant melanoma, who survived for at least ten years after initial examination, are presented. The depth of tumor invasion was 5 mm or less in all patients. The first patient received surgery and postoperative immunotherapy and she had no recurrence more than 18 years after treatment. The second patient underwent surgery but had local recurrence after 11 years. He underwent resection and postoperative chemotherapy and was still alive more than 14 years after initial examination. The third patient received radiotherapy and had metastasis nine months after treatment. Resection and radiotherapy were performed and the patient was alive more than 14 years after first presentation.

Influence of biopsy on the prognosis of cutaneous melanoma of the head and neck

BACKGROUND

This study was performed to determine the effect of biopsy type on survival rates and on local, regional, and distant metastasis in patients with head and neck cutaneous melanoma.

METHODS

A case series of 159 patients with melanoma of the head and neck referred to a tertiary-care center between 1983 and 1991, with a median follow-up of 38 months, was reviewed. Information analyzed included patient's age, sex, type of treatment, mode of biopsy, presence of residual melanoma in reexcision, location of lesion, presence of ulceration, Clark's level, Breslow thickness, and histologic type of the melanoma.

RESULTS

Excisional biopsy was performed in 79 patients, incisional biopsy in 48, and other procedures (shave, needle biopsy, cauterization, or cryotherapy) in 32. There were no significant pretreatment differences among the three groups in sex, thickness, histologic type, presence of nodal disease, or type of treatment. Pretreatment location of lesion was significantly different (p = .03) between the excisional and other biopsy types. Association between type of biopsy and survival rate was significant (p<.001):31.3% of patients in the incisional biopsy group died of disease, as did 25% of the other biopsy group, versus 8.9% of the excisional biopsy group; 31.3% of patients in the incisional biopsy group developed distant metastases, as did 28.1% of the other biopsy type, versus 10.1% of those in the excisional biopsy group (p = .01). There was no significant difference in local p = .37) or regional (p = 1.00) recurrence among the three biopsy groups. Multivariate analysis showed presence of tumor in the re-excision specimen, biopsy type, and nodal disease to be independent prognostic factors.

CONCLUSIONS

Our study suggests that the type of biopsy of cutaneous melanoma of the head and neck may influence the clinical outcome.

Mohs micrographic surgery fixed-tissue technique for melanoma of the nose

Mohs micrographic surgery, fixed-tissue technique, for excision of nasal melanoma provides three important benefits: 1) assurance of eradication of the main mass along with its "silent" contiguous outgrowths, 2) safe management of non-contiguous satellites too small to be visible initially, and 3) safe sparing of maximal amounts of surrounding normal tissues. These benefits are achieved because all incisions are through chemically fixed (killed) tissue, eliminating the danger of disseminating the highly transplantable melanoma cells and permitting the excision of successive layers for microscopic scanning of their undersurfaces by the systematic use of frozen sections. The process is continued to the termination of each ramification. There is no need to remove a wide margin of normal tissue as is customary with conventional surgery. Clinically invisible satellites are not moved or disturbed and can be removed safely by the same method if they appear. The reliability of the method is manifested by the 62.5% 5-year cure in a series of 10 consecutive patients, all of whom had no local recurrence after micrographic surgery.

Surgical management of malignant melanoma of the trunk and extremities

The surgical management of newly diagnosed melanoma should be tailored to the characteristics of the individual lesion. The actual thickness of the lesion is the main consideration in planning surgical treatment. Prophylactic lymphadenectomy is no longer routinely recommended. For early detection of clinically suspicious nodes, however, close follow-up of the patient is necessary so that therapeutic lymphadenectomy can be accomplished. Surgical intervention plays a limited role in the management of disseminated melanoma.

Cutaneous malignant melanoma in western Australia

The first detailed epidemiological and histological studies of cutaneous malignant melanoma in Western Australia have been undertaken recently. High and, apparently, increasing annual incidence rates have been confirmed (1975/76: 23.0/100 000 in males, 25.0/100 000 in females. 1980/81: 28.9/100 000 in males, 31.5/100 000 in females--rates for pre-invasive and invasive lesions combined). The results support a causal relationship of sunlight exposure with cutaneous melanoma in general, while suggesting that melanoma of Hutchinson's melanotic freckle type is related to continuous sun exposure whereas intermittent exposure is more important in the etiology of melanoma of superficial spreading type. The proposed etiological heterogeneity of melanoma and the dual origin theory of Mishima have been embodied in a theory of the etiology and histogenesis of melanoma which proposes that nodular melanoma is a common end result of the other types of melanoma rather than a distinct histogenetic entity. Some components of this theory have been supported by results of the 1980/81 West Australian Lions Melanoma Research Project. The overriding importance of tumour thickness as the most accurate histologic index of prognosis yet available has been emphasized by correlation with survival rates in Western Australia and the Oxford Region. Tumour thickness has also been shown to be the most reproducible of histological features, while others were subject to considerable interobserver variation. The better prognosis for melanoma patients in Western Australia compared with low incidence regions, when correlated with tumour thickness, indicated that melanoma is diagnosed earlier in areas of high incidence due to greater awareness of the risk.(ABSTRACT TRUNCATED AT 250 WORDS)

Malignant melanoma of the skin. I. The association of tumor depth and type, and patient sex, age, and site with survival

The occurrence and behavior of cutaneous melanomas in a group of 1123 patients studied prospectively, is described in terms of histologic type, tumor thickness and levels of invasion, the patients' sex and age, and the anatomic location of the primary tumors. Associations amongst these attributes, and with survival, are also examined. The characteristics of the patients in this study (who on average are somewhat younger, and have better prognoses and survivals than those reported by most other groups) are compared with data obtained (primarily over the past decade) in other geographical areas, and with different patient populations. Evidence is presented that sex, tumor location, and age (in the case of males) are also predictive of survival.

Survival from preinvasive and invasive malignant melanoma in Western Australia

The crude and relative survival rates from malignant melanoma of the skin were evaluated in 528 patients diagnosed in Western Australia in 1975-1976. Follow-up of patients to December 31, 1980 was 96% complete. For invasive malignant melanoma the relative five-year survival rates were 85% in men and 89% in women, while in cases of preinvasive melanoma both sexes experienced 100% relative five-year survival. The effects on prognosis of sex, anatomic site, clinical stage, level of invasion and tumor thickness were examined. Invasive melanomas of less than 0.76 mm in thickness also were associated with 100% relative survival. The variation in survival of melanoma patients with geographic location and the relative contributions of early diagnosis and biologic nature to the favorable outcome of melanoma in Australia are discussed.

Melanoma of the head and neck in Queensland

The incidence of melanoma in Queensland, 40 cases per 100,000 population, is the highest in the world. In this series of 740 melanomas over a 7-year period at the Royal Brisbane Hospital, 21.75% occurred on the head and neck. Of these, 46.5% arose in Hutchinson's melanotic freckle and 54.8% were histologically superficial, that is, Clark Levels I and II or less than 0.76 mm in thickness, or both. As local recurrence and distant metastasis is infrequent in superficial melanoma, less radical surgical excision of these lesions is advocated than for thicker lesions or those exhibiting a greater depth of invasion, where aggressive excision and even regional node dissection may be required. Anatomical variations in areas such as the nose, eyelid, ear, and scalp influence patterns of spread and necessitate differences in treatment at each site.

A histological comparison of cutaneous malignant melanoma between the Oxford Region and Western Australia

Two series of cutaneous malignant melanoma (CMM), one from a low incidence area (the Oxford Region) and one from a high incidence area (Western Australia), were compared by one pathologist using the same histological criteria. The findings included similarities in the distributions of histogenetic type of CMM, predominant cell type, and the degree and pattern of inflammatory reaction. Differences were found in other features including tumour profile, the presence of ulceration, mitotic activity, evidence of regression and level of invasion. The most important, and consistent morphological difference was the greater thickness of tumours from the Oxford Region, which is thought to be consistent with the theory that CMM is diagnosed at an earlier stage in high incidence areas because of greater medical and public awareness of the condition. Some problems in the use of accepted classifications of CMM are discussed.

The nature of melanoma. A critical review

The main object of this review was to examine the various histogenetic types of melanoma in order to determine their nature. Nodular melanoma and superficial spreading melanoma differ in the more rapid growth of the former. For tumors of equal depth of invasion in patients of the same sex, the prognoses are similar. Clinical features with prognostic significance are sex, age, and site of the lesion. Women have a decided superiority in survival up to the age of about 50 years when their superiority declines. Survival rates for men also decline after the age of 50 years but to a lesser degree. Melanomas of the extremities have a better prognosis than melanomas of the axial regions. The histological feature of most prognostic significance is depth of invasion (thickness). Ulceration is partly bound to thickness of the lesion, but has an augmentative effect of its own which is related to rate of growth. Thin lesions with or without regression are often associated with metastases. Melanomas arising in Hutchinson's melanotic freckle have a better prognosis than nodular or superficial spreading melanoma but there has not been any series large enough for definitive markers with prognostic significance to be determined. A similar state pertains in palmar, plantar and subungual melanomas. The initial surgical approach in nodular and superficial melanoma should be based upon the thickness of the tumour, site of the tumour, and sex of the patient. The current classification of malignant melanoma is unsatisfactory. Melanoma arising in Hutchinson's melanotic freckle seems to be a distinct entity. Melanomas of other histogenetic types would be best classified according to site.

Survival of cutaneous malignant melanoma patients at University of Iowa Hospitals: 1950--1974

Survival of 387 patients treated for cutaneous malignant melanoma at University of Iowa Hospitals during the period 1950--1974 was analyzed. For the entire period, the observed five-year survivals were 57% for women and 33% for men; the corresponding ten-year survivals were 43 and 23%. For both men and women, there was an impressive improvement in outcome between the earliest and the latest periods, so that for 1970--1974, the five-year observed survival was 68% for women and 49% for men. Data are presented on mean age at diagnosis, distribution by stage, site, and sex, and survival by site and sex. The question is raised whether the biologic nature of malignant melanoma is variable, so that increased incidence is associated with better prognosis.

Is malignant melanoma arising in a Hutchinson's melanotic freckle a separate disease entity?

Several features which distinguish malignant melanoma arising in a Hutchinson's melanotic freckle (HMFM) from other types of malignant melanoma (MM) are described. Forty-eight patients with HMFM of the head and neck region were compared with 98 patients with MM of the head and neck region. All patients were clinical stage I. There was a preponderance of women amongst HMFM patients but not MM patients and HMFM patients were significantly older than MM patients. Although HMFM patients had thicker tumours than MM patients, these thicker lesions had a lower degree of mitotic activity and a higher incidence of partial regression. Overall prognosis for HMFM patients was significantly better than for MM patients, this being particularly so for women, none of whom died of melanoma. There was no close correlation between prognosis of HMFM patients and the thickness of their tumours. Every one of the HMFM in this study displayed evidence of severe solar degeneration, but such degeneration per se did not appear to confer upon these lesions their benign biological behaviour.

Histologic features of tumors and the female superiority in survival from malignant melanoma

The primary tumors of 780 patients with clinical Stage I malignant melanoma were reviewed to seek reasons for the female superiority in survival. Histologic features of tumors believed to be of prognostic significance were examined: tumor thickness, evidence of regression, histogenetic type, and mitotic activity. The average tumor thickness was significantly less in women, due to a preponderance of very thin lesions in women and very thick lesions in men. In both men and women, there proved to be a direct correlation between five-year survival rate and tumor thickness, but women had a higher survival rate than men at each thickness level. These latter two findings, in combination, could contribute to the overall female superiority in survival. No further insight into the sex difference in survival was obtained from the examination of the other histologic features. Although the incidence of partial lesion regression was not markedly different except for very thin lesions. There were no disparities between the sexes in the incidences of histogenetic types or grades of mitotic activity, two histologic features which drew their prognostic significance only from their correlation with tumor thickness.

Prognostic significance of the histological features of malignant melanoma

A review of 694 patients with localized cutaneous malignant melanoma (clinical stage I) revealed that three histological features of the primary lesion had no effect of their own on survival rate but derived their prognostic significance only because of their close correlation with tumour thickness. Primary lesions of superficial spreading histogenetic type, or of low mitotic activity or showing evidence of partial regression appeared to have a more favourable prognosis than lesions of nodular histogenetic type or of high mitotic activity or showing no regression. However, the former three histological features were predominant in thin lesions which had a better prognosis than thicker lesions. It was concluded that these features exerted only an indirect effect upon survival, tumour thickness being the most important prognostic determinant.

Excisional biopsy and delayed wide excision versus primary wide excision of malignant melanoma

In a retrospective study of 269 cutaneous malignant melanomas in stage I the influence of biopsy on survival was studied. Sixty patients were treated with primary wide excision and 209 patients with excisional biopsy followed by wide excision. The 5-year survival rates for the two groups were 75.0% and 82.8% respectively. There was an equal distribution of prognostic factors such as thickness, level of invasion, presence of ulceration, location and maximal size of the tumours in the two groups. As excisional biopsy with subsequent wide excision gives an accurate histopathologic diagnosis and permits a more rational treatment of thin melanomas, this form of treatment is recommended.

The comprehensive cancer centre

Comprehensive cancer centres have arisen around the world, very often on the foundations of radiotherapy departments, as in the case of the Cancer Institute in Melbourne. Such centres offer the complete non-surgical approach to cancer through multidisciplinary interaction with full diagnostic back-up, and are centres of excellence in at least one branch of surgical oncology. They are physically or organizationally autonomous entities. They undertake basic as well as clinical research. They provide training of personnel in cancer diagnosis, treatment and research.

Aspects of surgical treatment for malignant melanoma: the place of biopsy and wide excision

Biopsy of melanoma is discussed in respect of the operator, the adequacy of biopsy, and the time delay till wide excision; statistics are taken from a series of 509 patients with this disease who had their definitive surgery and review at the Peter MacCallum Clinic between 1954 and 1973. Wide excision is described in respect of its origins and its proponents, and discussion draws on appropriate material from the series.