Calvin L. Day

The malignant potential of small congenital nevocellular nevi: An estimate of association based on a histologic study of 234 primary cutaneous melanomas

In order to assess a relationship between small congenital nevocellular nevi and cutaneous melanoma, histologic features commonly associated with congenital nevi were sought in 234 melanomas. The detection of one or more histologic features of congenital nevi in 8.1% (19/234) of melanoma specimens was directly related to the number of slides and tissue sections with melanoma available for review, the predominance of superficial spreading melanoma (SSM) and the historic relationship to a preexisting pigmented nevus at the tumor site. The histologic association was inversely related to melanoma thickness and tumor location on the lower extremities. The observed frequency of histologic association was estimated to be approximately 4,000 to 13,000 times greater than expected on the basis of surface area by chance alone. These findings suggest that small congenital nevi may be precursors for at least some cases of cutaneous melanoma. The strength of histologic association is highly dependent on the specificity of methods used for detecting congenital nevi in melanoma specimens.

Dysplastic melanocytic nevi in histologic association with 234 primary cutaneous melanomas

Dysplastic melanocytic nevi (DMN) are irregularly pigmented lesions characterized by (1) atypical melanocytic hyperplasia in a lentiginous epidermal pattern (AMHL), (2) one or more dermal mesenchymal changes, and (3) frequently a dermal nevocellular nevus. In order to determine an association between DMN and cutaneous melanoma, the dominant histologic feature of DMN (namely, AMHL) was sought in histologic contiguity with 234 primary melanomas. Of these 234 cases, 9 were lentigo maligna melanomas. Of the remaining 225 cases, 49 (21.8%) were associated with AMHL in the same histologic section as (but beyond the most lateral margin of) intraepidermal and invasive melanoma. AMHL was directly associated with the presence of dermal nevocellular nevi in histologic contiguity with melanoma, and a greater number of histologic slides with melanoma available for review. AMHL was inversely associated with nodular melanoma. Most of the AMHL cases were not associated with familial melanoma, but the total number of familial cases was low. The histologic association between AMHL and melanoma in one fifth of cases in this series supports the hypothesis that at least some cutaneous melanomas may have an origin in DMN.

Prognostic Factors for Patients with Clinical Stage I Melanoma of Intermediate Thickness (1.51–3.99 mm)* A Conceptual Model for Tumor Growth and Metastasis

Fourteen variables were tested for their ability to predict visceral or bony metastases in 177 patients with clinical Stage I melanoma of intermediate thickness (1.51–3.99 mm). A Cox multivariate analysis yielded a combination of four variables that best predicted bony or visceral metastases for these patients: 1) mitoses > 6/mm2 (p = 0.0007), 2) location other than the forearm or leg) p = 0.009), 3) ulceration width > 3 mm (p = 0.04), and 4) microscopic satellites (p = 0.05). The overall prognostic model chi square was 32.40 with 4° of freedom (p < 10-5). Combinations of the above variables were used to separate these patients into at least two risk groups. The high risk patients had at least a 35% or greater chance of developing visceral metastases within five years, while the low risk group had greater than an 85% chance of being disease free at five years. Criteria for the high risk group were as follows: 1) mitoses > 6/mm2 in at least one area of the tumor, irrespective of primary tumor location, or 2) a melanoma located at some site other than the forearm or leg and histologic evidence in the primary tumor of either ulceration > 3 mm wide or microscopic satellites. The low risk group was defined as follows: 1) mitoses ≤ 6/mm2 and a location on the leg or forearm, or 2) mitoses ≤ 6/mm2 and the absence in histologic sections of the primary tumor of both microscopic satellites and ulceration ≥ 3 mm wide. The number of patients in this series who did not undergo elective regional node dissection (N = 47) was probably too small to detect any benefit from this procedure. Based on survival rates from this and other studies, it is estimated that approximately 1500 patients with clinical Stage I melanoma of intermediate thickness in each arm of a randomized clinical trial would be needed to detect an increase in survival rates from elective regional node dissection.

Prognostic factors for melanoma patients with lesions 0.76 - 1.69 mm in thickness. An appraisal of "thin" level IV lesions.

Fourteen variables were tested for their prognostic usefulness in 203 patients with clinical Stage I melanoma and primary tumors 0.76–1.69 mm thick. Only two variables, primary tumor location and level of invasion, were useful in predicting death from melanoma for these patients. Of the 12 deaths from melanoma, 11 occurred in patients with primary tumors located on the upper back, posterior arm, posterior neck, and posterior scalp (= BANS). There has been only one death from melanoma in 136 patients with melanoma located at other sites (11/67 vs 1/136, p < 0.0001 Fishers Exact Test). Of the 67 BANS patients, 51 had level II or level III lesions and five (10%) died of melanoma. This compares with six deaths from melanoma in 16 patients (37.5%) with level IV BANS lesions (5/51 vs 6/16, p = 0.01 Fishers Exact Test). The relatively high incidence of both melanoma deaths and regional node metastases for the BANS group merits consideration for testing the efficacy of elective regional node dissection for these patients.

Malignant melanoma patients with positive nodes and relatively good prognoses: Microstaging retains prognostic significance in clinical stage I melanoma patients with metastases to regional nodes

Fifteen yariables were tested for their value in predicting recurrent disease in 46 clinical Stage I melanoma patients with metastases to regional nodes. A stepwise proportional hazards general linear model (Cox multivariate analysis) separated these melanoma patients with regional node metastases into at least two risk groups. Twenty patients in the relatively low‐risk group had a five‐year disease‐free survival of 80% (in spite of having nodal metastases). This compares to a five‐year disease‐free survival of 17.5% for 26 patients in the high‐risk group (P < 0.001, Lee‐Desu Statistic). Criteria for the high‐risk group required that a patient have only one of the following two values: (1) The number of regional lymph nodes that contained tumor divided by the total number of nodes removed × 100% (percentage of positive nodes) ≥20%; or (2) a primary tumor thickness of >3.5 mm (regardless of node percentage). Conversely, patients in the low‐risk group had neither of the above features. The high‐risk group could further be stratified by the lymphocytic response at the base of the tumor. These findings have direct immediate application to the elective regional node dissection controversy and to adjuvant therapy studies containing these patients. Cancer 47:955–962, 1981.

“Microscopic satellites” are more highly associated with regional lymph node metastases than is primary melanoma thickness

A multivariate analysis was performed on 20 clinical and histologic variables from 327 Stage I prospectively studied melanoma patients who underwent elective regional lymph node dissection (ERLD). Primary tumor thickness, microscopic satellites, and the elapsed interval between diagnosis and ERLD, were selected as the combination of variables that were most highly associated with clinically occult regional lymph node metastases (P = 10−15, model chi‐square). Microscopic satellites were defined as tumor nests, >0.05 mm in diameter, in the reticular dermis, panniculus, or vessels beneath the principal invasive tumor mass but separated from it by normal tissue on the section in which the Breslow measurement was taken. The probability of finding nodal metastases for melanomas <0.75 mm thick was 0% (0/41 patients); for those 0.76–1.50 mm, 4% (4/108); 1.51–3.0 mm, 14% (14/102); and >3.0 mm, 39.5% (30/76). Primary melanomas >1.50 mm thick with microscopic satellites were more often associated with nodal metastases than those of similar thickness without satellites (30/57 (53%) versus 14/121 (12%), P = 0.01). Some satellites probably represent intraspecimen metastases, while others do not. Any predictive model for occult regional lymph node metastases based on data from ERLD done <50 days after diagnosis may underestimate the prevalence of metastases.

Lentigo maligna melanoma has no better prognosis than other types of melanoma.

We studied 48 patients with lentigo maligna melanoma (LMM) and compared the clinical stage I patients with non-LMM melanoma patients (matched by site and thickness) to see if prognosis differed. There was no significant difference in mortality from melanoma between the two groups (P = .68) after a mean follow-up time of five years (67.5 months for LMM, 60.5 months for non-LMM). In addition, a Cox multivariate analysis of the entire matched group showed that only thickness was significantly associated with death from melanoma (P = .0007) while histology (LMM v non-LMM) did not make a significant contribution (P = .61). Our data suggest that after accounting for primary tumor thickness and site, LMM and non-LMM have the same prognosis and biologic behavior, in contrast to the widely held belief that LMM has a better prognosis than other forms of melanoma.

Narrower margins for clinical stage I malignant melanoma.

Panic after a diagnosis of cutaneous malignant melanoma commonly arises from fears of early death and disfiguring surgery. Yet, in the United States today, most cutaneous melanomas are diagnosed wh...

A prognostic model for clinical stage I melanoma of the upper extremity. The importance of anatomic subsites in predicting recurrent disease.

Thirteen variables were studied for their relative usefulness in predicting recurrent disease in 107 patients with clinical Stage I melanoma of the upper extremity. After a mean follow-up period of 54 months, the only patients who have had recurrent disease to date are those whose primary lesions were located either on the hand or posterior upper arm. The five-year, disease-free survival role for 44 patients with melanoma at these sites was 68%. None of 63 patients with melanoma located on the forearm of anterior upper arm have had recurrent disease (i.e., the five-year, disease-free survival rate was 100% (p = 0.00004), compared with the hand or posterior arm group). A Cox proportional hazards (multivariate) analysis demonstrated that two primary tumor histologic variables, thickness in millimeters and ulceration, interacted to produce the best prognostic model for those 44 patients with melanoma of the hand or posterior upper arm. Twenty-one

A multivariate analysis of prognostic factors for melanoma patients with lesions greater than or equal to 3.65 mm in thickness. The importance of revealing alternative Cox models.

Fourteen prognostic factors were examined in 79 patients with clinical Stage I melanoma greater than or equal to 3.65 mm in thickness. All nine patients with melanoma of the hands or feet died of melanoma. A Cox proportional hazards (multivariate) analysis of the remaining 70 patients showed that a combination of the following four variables best predicted bony or visceral metastases: 1) a nearly absent or minimal lymphocyte response at the base of the tumor, 2) histologic type other than superficial spreading melanoma, 3) location on the trunk, and 4) positive nodes or no initial node dissection. Ulceration and/or ulceration width were not useful in predicting outcome either singly or in combination with other variables. Patients with negative lymph nodes and primary tumors of the trunk, hands, and feet did not do better than patients with positive nodes at those sites. Conversely, non of 16 patients with negative lymph nodes and extremity melanomas (excluding the hands and feet) or head and neck melanomas developed visceral or bony metastases (i.e., five-year disease-free survival rate 100%).