A. Hafeez Diwan

Microscopic Tumor Burden in Sentinel Lymph Nodes Predicts Synchronous Nonsentinel Lymph Node Involvement in Patients With Melanoma

PURPOSE We and others have demonstrated that additional positive lymph nodes (LNs) are identified in only 8% to 33% of patients with melanoma who have positive sentinel LNs (SLNs) and undergo complete therapeutic LN dissection (cTLND). We sought to determine predictors of additional regional LN involvement in patients with positive SLNs. PATIENTS AND METHODS Patients with clinically node-negative melanoma who underwent SLN biopsy (1991 to 2003) and had positive SLNs were identified. Clinicopathologic factors, including extent of microscopic disease within SLNs, were evaluated as potential predictors of positive non-SLNs. RESULTS Overall, 359 (16.3%) of the 2,203 patients identified had a positive SLN. Positive non-SLNs were identified in 48 (14.0%) of the 343 patients with positive SLNs who underwent cTLND. On univariate analysis, several measures of SLN microscopic tumor burden, one versus three or more SLNs harvested, tumor thickness more than 2 mm, age older than 50 years, and Clark level higher than III were predictive of positive non-SLNs; primary tumor ulceration and number of positive SLNs had no apparent impact. On multivariable logistic regression analysis, measures of SLN microscopic tumor burden were the most significant independent predictors of positive non-SLNs; tumor thickness more than 2 mm and number of SLNs harvested also predicted additional disease. A model was developed that stratified patients according to their risk for non-SLN involvement. CONCLUSION In melanoma patients with positive SLNs, SLN tumor burden, primary tumor thickness, and number of SLNs harvested may be useful in identifying a group at low risk for positive non-SLNs and be spared the potential morbidity of a cTLND.

Use of p63 expression in distinguishing primary and metastatic cutaneous adnexal neoplasms from metastatic adenocarcinoma to skin

Absract:  p63, a recently identified homologue of the p53 gene, is mainly expressed by basal and myoepithelial cells in skin. Others and we have shown the value of p63 in distinguishing primary adnexal tumors from visceral adenocarcinomas metastatic to skin. We now investigate the pattern of p63 expression in metastases from skin adnexal carcinomas and their cognate primaries and evaluate p63 expression in a larger case series of malignant cutaneous adnexal neoplasms. Immunohistochemical analysis for p63 was performed on 13 metastases of adnexal carcinomas and their corresponding primary tumors. Twenty visceral metastatic adenocarcinomas to the skin and 7 primary mucinous carcinomas with cutaneous or visceral origin were compared. The majority (90.9%) of primary adnexal tumors strongly expressed p63 and their metastases labeled similar to their cognate primary tumors. With one exception, primary or metastatic mucinous carcinomas did not express p63. Metastases from two apocrine carcinomas lacked p63 expression. All other cutaneous metastases from internal adenocarcinomas were negative for p63. Analysis of p63 expression may assist in the differential diagnosis of primary adnexal carcinomas versus metastatic visceral adenocarcinomas to the skin. Metastases from adnexal carcinomas generally retain p63 expression similar to their associated primary tumors.

Expression of p63 in primary cutaneous adnexal neoplasms and adenocarcinoma metastatic to the skin

p63, a recently identified homologue of the p53 gene, has been reported to be essential in the development of epithelia and is mainly expressed by basal and myoepithelial cells. The purpose of this study was to investigate the pattern of p63 expression in cutaneous adnexal neoplasms and to assess its possible value in the differential diagnosis of primary cutaneous neoplasms vs adenocarcinomas metastatic to the skin. Immunohistochemical analysis for p63 was performed on formalin-fixed, paraffin-embedded archival tissue from 20 benign adnexal tumors, 10 malignant adnexal tumors and 14 adenocarcinomas metastatic to the skin. The expression of p63 was evaluated in epidermal cells, skin appendages and metastatic tumor cells. p63 was consistently expressed in the basal and suprabasal cells of epidermis and cutaneous appendages, including the basal/myoepithelial cells of sweat glands. Out of 20 benign adnexal tumors, 13 (65%) showed strong (score 3) p63 expression; the remaining seven (35%) cases had score 2. All primary cutaneous carcinomas, including adenocarcinomas, expressed p63. In contrast, none of the metastatic adenocarcinomas to the skin was positive for p63 (P<0.001). Based on our findings, analysis of p63 expression may help in the differential diagnosis of primary vs metastatic cutaneous adenocarcinomas.

Galectin-3 Expression Is Associated with Tumor Progression and Pattern of Sun Exposure in Melanoma

Purpose: Most studies accept a multistep pathogenic process in melanoma that may include the phases of benign nevi and dysplastic nevi, melanoma, and metastatic melanoma. Dysregulation of cellular proliferation and apoptosis is probably involved in melanoma progression and response to therapy. We have studied the expression of galectin-3, a β-galactoside-binding protein involved in apoptosis, angiogenesis, and cell proliferation, in a large series of melanocytic lesions, and correlated the expression with clinical and histologic features. Experimental Design: Tissue microarray blocks of 94 melanocytic lesions were semiquantitatively evaluated by immunohistochemistry for the cytoplasmic or nuclear expression of galectin-3. Results: Primary and metastatic melanomas expressed galectin-3 at a significantly higher level than nevi in both cytoplasm and nuclei (P < 0.0073). There was a significant association between anatomic source (as indirect indication of level of sun-exposure) and cytoplasmic and nuclear expression. Lymph node and visceral metastases had a higher level of expression than s.c. lesions (P < 0.004). Interestingly, there was an almost significant finding of worse survival in those patients with lesions showing higher levels of cytoplasmic than nuclear galectin-3 expression (log-rank test, P = 0.06). Conclusions: Melanocytes accumulate galectin-3 with tumor progression, particularly in the nucleus. The strong association of cytoplasmic and nuclear expression in lesions of sun-exposed areas suggests an involvement of UV light in activation of galectin-3.

Site and tumor type predicts DNA mismatch repair status in cutaneous sebaceous neoplasia.

Cutaneous sebaceous neoplasia is known to exhibit a high degree of DNA mismatch repair (MMR) deficiency leading to microsatellite instability and these tumors can be markers of the Muir-Torre syndrome and internal malignancy. Other tumors, such as colonic carcinoma, show tendencies toward particular histologic features and sites of involvement correlating with MMR deficiency. There are few comprehensive studies of unselected cutaneous sebaceous neoplasms. To address this gap in knowledge, we examined 94 sebaceous neoplasms from 92 patients and 17 sebaceous hyperplasia controls using immunohistochemistry for MLH1, MSH2, and MSH6. Our results indicate that MMR deficiency is significantly associated with anatomic location (more frequently in the trunk and extremities as compared with head and neck), tumor type (more often in adenoma compared with carcinoma within the head and neck region), and architecture (keratoacanthomalike). No correlation between cystic change and MMR deficiency was noted. Cutaneous sebaceous neoplasia has tendencies toward certain tumor types and anatomic distribution based on MMR status analogous to that seen in colonic carcinomas and other tumors. These may be helpful indicators for further workup for the Muir-Torre syndrome.

Immunohistochemical detection of lymphovascular invasion with D2-40 in melanoma correlates with sentinel lymph node status, metastasis and survival

Using immunohistochemistry with anti‐D2‐40 for the detection of lymphovascular invasion (LVI‐IHC) in 74 cases of invasive melanoma, we found LVI in 23% (16/74) of the tumors. Data on sentinel lymph node (SLN) biopsy were available for 36 patients. Sixty‐seven percent (6/9) of patients with LVI‐IHC and 19% (5/27) without LVI‐IHC had positive SLN. Follow‐up data were available for 60 patients. Data on recurrence/metastasis were available for 60 patients. Twenty‐five percent (15/60) had LVI with immunohistochemistry. Fifty‐three percent (8/15) of these patients had “distant” metastasis or regional recurrence compared with 11% (5/45) in those without LVI‐IHC. Overall and disease‐specific survival was shorter for patients with LVI. In both the univariate and multivariate Cox proportional hazards regression models, LVI‐IHC in addition to ulceration was statistically significant with respect to overall survival. Specifically, in the reduced multivariate model, compared with patients with no LVI, patients with intratumoral LVI had a hazard ratio (HR) of 5.4 (95% CI 1.6–18.4), while patients with peritumoral LVI had a HR of 3.8 (95% CI 0.7–20.9). In addition, patients with ulceration had an increased hazard of 4.4 (95% CI 1.2–16.8).

Multiple Squamous Cell Carcinomas of the Skin After Therapy With Sorafenib Combined With Tipifarnib

BACKGROUND Keratoacanthomas, as well as an actinic keratosis progressing to squamous cell cancer, have been reported in patients who were treated with sorafenib, a multikinase inhibitor known to suppress the actions of Raf kinase and vascular endothelial growth factor receptor. OBSERVATIONS We describe a 70-year-old white woman with metastatic renal cell carcinoma who was treated with a combination of sorafenib and tipifarnib (a farnesyltransferase inhibitor). She had no history of skin cancer. However, within 3 months after starting this therapy, she developed 3 erythematous nodules on her legs. Pathologic examination showed deeply invasive, well-differentiated squamous cell carcinomas. The tumors were excised, and sorafenib-tipifarnib treatment was discontinued. No new lesions have developed to date. CONCLUSIONS Targeted agents, such as sorafenib and tipifarnib, are increasingly being used in the management of visceral malignant neoplasms. A temporal relationship was observed between the initiation of the targeted treatments and the emergence of these cutaneous cancers. Further study of the mechanisms responsible for the rapid appearance of squamous cell cancers in this setting may provide insights into the pathogenesis of skin tumors.

Metastatic hidradenocarcinoma with demonstration of Her-2/neu gene amplification by fluorescence in situ hybridization: Potential treatment implications

Abstract:  A 44‐year‐old man was referred for a right chest nodule of 3 months duration. A ‘benign’ nodule had been excised from this location 8 years prior. On examination, palpable nodes were noted in the right axilla. Radiographic studies were significant only for right axillary lymphadenopathy. Histologically, a nodular dermal proliferation composed of poorly differentiated epithelioid cells in nests and focally forming ducts with pseudopapillary architecture comprised the primary tumor. Features of a clear cell hidradenoma were noted focally. Immunohistochemical (IHC) analysis revealed reactivity for HMW cytokeratins, CK5 and CK7, p53, p63, CEA (focal), androgen receptor, EGFR, estrogen receptor (ER), MUC5AC, and strong/diffuse membranous staining for Her‐2/neu. Negative stains included villin, TTF‐1, CDX2, S‐100 protein, vimentin, gross cystic disease fluid protein 15 (GCDFP‐15), mammoglobulin, and MUC2. A wide local excision and axillary node dissection was performed. Metastatic tumor involved nine of 28 nodes. Interphase fluorescence in situ hybridization (FISH) demonstrated chromosomal amplification of the Her‐2/neu locus within the tumor and a nodal metastasis. The patient has completed adjuvant and radiotherapy, including trastuzumab, and is asymptomatic. We believe this to be the first demonstration of Her‐2/neu amplification in a malignant skin adnexal tumor. In analogy to breast carcinoma, these findings suggest the applicability of trastuzumab for patients with metastatic adnexal carcinomas demonstrating Her‐2/neu amplification.

Primary Sézary Syndrome Commonly Shows Low-Grade Cytologic Atypia and an Absence of Epidermotropism

The dermatopathologic findings in cases of Sézary syndrome (SS) that arise in patients without a previous diagnosis of mycosis fungoides have not been well characterized. We evaluated the histologic findings in skin biopsy specimens from 31 patients with such primary SS and correlated them with clinical and hematologic parameters at the time of biopsy. The most characteristic histologic finding was the presence of a dermal perivascular lymphoid infiltrate, usually with mild to moderate cytologic atypia and variable numbers of eosinophils; epidermotropism was absent or minimal in 19 cases (61%). Reactive epidermal changes such as spongiosis, parakeratosis, and acanthosis also were present frequently (27 [87%], 17 [55%], 19 [61%] cases, respectively). The number of eosinophils present in skin biopsy specimens correlated with the level of peripheral blood lymphocytosis. In erythrodermic patients or patients with persistent xerosis and pruritus, it is important to carefully evaluate the degree of lymphocyte atypia in the dermal perivascular infiltrate and correlate with blood flow cytometric findings to diagnose primary SS. Many cases will lack the epidermotropism usually seen in mycosis fungoides.

Loss of claudin-1 expression in tumor-associated vessels correlates with acquisition of metastatic phenotype in melanocytic neoplasms

Abstract:  Claudins are a family of transmembrane proteins involved in cell‐to‐cell adhesion and are believed to be the main component of tight junctions. Recent studies have suggested that some metastatic solid tumors lack claudin expression. It is unknown whether claudins play a role in cutaneous melanoma. Immunohistochemical studies were performed on tissue microarrays containing 19 benign melanocytic nevi (BN), 21 dysplastic nevi (DN), 23 primary malignant melanomas (MMs), and 31 metastatic melanomas (MMMs) using a polyclonal anti‐claudin‐1 antibody. Immunoreactivity in tumor cells and associated vessels was graded by intensity and by percentage of reactive cells. Normal epidermis served as internal control (3+ labeling). Cases with at least 2+ labeling in more than 25% of the cells were considered positive. Claudin‐1 expression was present in 37% of BN, 24% of DN, 26% of MM, and 3.2% of MMM. Tumor‐associated vessels showed the following results: 11 of 19 (58%) in BN, 14 of 21 (67%) in DN, 17 of 23 (74%) in MM, and 6 of 31 (19%) in MMM. A significant loss of expression was noted between MMM and all other lesions in tumor cells and associated vessels. There was no significant difference between BN, DN, and MM. Within primary melanomas, there was a significant correlation between expression of claudin in tumor cells and Clark level/Breslow thickness. Also significant was a decreased expression of claudin in tumor vessels of lesions with higher Breslow thickness or Clark level. These data suggest that loss of claudin‐1 may play a significant role in the acquisition of metastatic phenotype in cutaneous melanoma.