Risk Factors Predicting Positive Margins at Primary Wide Local Excision of Cutaneous Melanoma

Mohs micrographic surgery in the surgical treatment paradigm of melanoma in situ and invasive melanoma: A clinical review of treatment efficacy and ongoing controversies

Mohs Micrographic Surgery (MMS) for treatment of melanoma offers several advantages over wide local excision (WLE), including complete histologic margin evaluation, same-day resection and closure, and sparing of healthy tissue in critical anatomic sites. Recently, a large volume of clinical data demonstrating efficacy in MMS treatment of melanoma was published, leading to emerging patient safety considerations of incurred treatment costs, risk of tumor upstaging, and failure of care coordination for sentinel lymph node biopsy (SLNB). MMS offers a safe, effective, and value-based treatment for both melanoma in situ (MIS) and invasive melanoma (IM), particularly with immunohistochemistry use on frozen sections. Compared to wide local excision, MMS treatment demonstrates similar or improved outcomes for local tumor recurrence, melanoma-specific survival, and overall survival at long-term follow-up. Tumor upstaging risk is low, and if present, alteration to clinical management is minimal. Discussion of SLNB for eligible head and neck IM cases should be done prior to MMS. Though challenging, successful multidisciplinary coordination of SLNB with MMS has been demonstrated. Herein, we provide a detailed clinical review of evidence for MMS treatment of cutaneous melanoma and offer recommendations to address current controversies surrounding the evolving paradigm of surgical management for both MIS and invasive melanoma (IM).

A Retrospective Study of Re-excised Skin Cancers in a Pathology Center

Surgical re-excision is the recommended treatment for the complete removal of incompletely excised skin cancers (SCs), but it may not always lead to this goal. In the present study, the re-excision rate and the presence of residual tumors in re-excised SCs were evaluated. In this retrospective descriptive study, the pathological archives of a hospital center were examined for incompletely excised tumors. Out of the 96 incompletely excised tumors, 19 cases (19.8%) underwent re-excision, of which residual tumors were observed again in 7 cases (36.8%). The highest rate of residual tumor was found in the cheek (66.66%), and the involvement with tumor remnants of both margins combined was greater than the involvement of each of the lateral and deep margins alone. Collecting and reporting of surgical results of re-excised tumors may assist clinicians in determining the patient's condition and making appropriate decisions to increase the success rate of reoperations.

The Facial Artery Perforator Flap

BACKGROUND

Reconstruction of facial melanoma defects can be challenging. Large defects of the midface, cheek, and nasolabial fold are often reconstructed using a cervicofacial flap which requires significant flap elevation and undermining. Surgeons are often hesitant to commit to such a large reconstruction without definitive pathologic evidence of negative margins. However, local perforator flaps may be used as an alternative to large flaps with less dissection and donor site morbidity and may also allow for more facile re-advancement in the event of a positive margin on final pathology. The goal of this study is to evaluate a perforator flap based on the facial artery to determine if it is a safe and cosmetically favorable option to immediately repair oncologic-related defects on the cheek and midface.

METHODS

A retrospective review of all melanoma cases performed by the senior author between January 2016 and December 2021 was conducted. Patients who underwent reconstruction using a facial artery perforator flap were included.

RESULTS

Sixteen patients were included in our cohort. The average age was 67.3 years and 53% (n=8) were female. Fourteen patients had the primary defect located on the cheek, 1 from the nasolabial fold, and 1 from the distal nasal sidewall. All patients received immediate reconstruction. Excisional margins ranged from 0.5 to 2 cm. Two patients had positive margins following pathology results with one undergoing treatment with imiquimod and the other opting for re-excision. No complications involving the defect or donor site were reported after an average follow-up time of 113.8 days.

CONCLUSION

The facial artery perforator flap is a safe and cosmetically favorable option to immediately repair oncologic-related defects on the cheek and midface.

Assessing Rates of Positive Surgical Margins After Standard Excision of Vulvar Melanomas

BACKGROUND

Vulvar melanoma is a rare malignancy with frequent recurrence and poor prognosis. National guidelines recommend wide local excision of these tumors with allowances for narrower margins for anatomic and functional limitations, which are common on specialty sites. There is presently a lack of data of margin positivity after standard excision of vulvar melanomas.

OBJECTIVE

We aim to evaluate the rate of positive margins after standard excision of vulvar melanomas.

MATERIALS AND METHODS

Retrospective cohort study of surgically excised vulvar melanomas from the NCDB diagnosed from 2004 to 2019.

RESULTS

We identified a total of 2,226 cases. Across surgical approaches and tumor stages, 17.2% (Standard Error [SE]: 0.8%) of cases had positive surgical margins. Among tumor stages, T4 tumors were most commonly excised with positive margins (22.9%, SE: 1.5%). On multivariable survival analysis, excision with positive margins was associated with significantly poorer survival (Hazard Ratio 1.299, p = .015).

CONCLUSION

We find that positive margin rates after standard excision of vulvar malignancies are higher than for other specialty site melanomas. Our data suggest that use of surgical approaches with complete margin assessment may improve local control and functional outcomes for patients with vulvar melanoma as they have for patients with other specialty site melanomas.

Principles of Surgery in Head and Neck Cutaneous Melanoma

Surgical management of head and neck melanoma starts from the primary biopsy of the cutaneous site by a narrow excision with a 1 to 3 mm margins. The margin should include the whole breadth and sufficient depth of the lesion. The key is not to transect the lesion. With the advent of molecular testing, gene expression profiling, and immunotherapies, the surgical management of advanced melanoma has changed. Sentinel lymph node biopsy is an essential armamentarium for T2a and higher staging/greater than 1 mm thick and advance stage disease. Molecular pathogenesis and cancer immunology are recognized in the recent treatment protocols along with surgery in advanced stages of melanoma.

Local Recurrence of Melanoma Is Higher After Wide Local Excision Versus Mohs Micrographic Surgery or Staged Excision: A Systematic Review and Meta-analysis

BACKGROUND

Complete removal of melanoma is a primary goal of excision, and local recurrence is one measure to evaluate the efficacy of surgical technique.

OBJECTIVE

To compare published local recurrence rates for melanoma treated with Mohs micrographic surgery (MMS) or staged excision versus wide local excision (WLE).

METHODS AND MATERIALS

Search of 6 databases identified comparative and noncomparative studies that reported local recurrence rates after MMS, staged excision, or WLE for melanoma. Random-effects meta-analysis was used to estimate odds ratios and 95% confidence interval (CI) from comparative studies and event rates from noncomparative studies.

RESULTS

Of the 71 studies included (16,575 patients), 12 were comparative studies (2,683 patients) and 56 were noncomparative studies (13,698 patients). Comparative studies showed increased recurrence after WLE compared with MMS or staged excision (odds ratio [OR], 2.5; 95% CI, 1.4-4.6) and compared with MMS alone (OR, 3.3; 95% CI, 1.8-5.9). Pooled data from comparative and noncomparative studies showed a local recurrence rate of 7% after WLE (95% CI, 5%-11%), 3% after staged excision (95% CI, 2%-4%), and less than 1% after MMS (95% CI, 0%-1%). Statistical heterogeneity was moderate to high.

CONCLUSION

Local recurrence of melanoma is significantly lower after MMS (<1%) and staged excision (3%) compared with WLE (7%).

Morbidity and Mortality of Melanoma on the Trunk and Extremities Treated With Mohs Surgery Versus Wide Excision: A Systematic Review

BACKGROUND

Recommendations for the approved use of Mohs surgery for cutaneous melanoma on the trunk and extremities remain uncertain.

OBJECTIVE

To compare survival and recurrence between patients treated with Mohs surgery versus wide excision for melanoma on the trunk and extremities.

METHODS

The databases Medline, Embase, Web of Science, CENTRAL, and EMCare were searched from inception on January 11, 2021. Contemporary comparisons were included exclusively. Meta-analysis was conducted using generic inverse variance and a fixed effects model.

RESULTS

Four studies were eligible for inclusion. The study population (n = 279,556) was 52.1% men and 97.2% White. There were no observed differences in 5-year overall survival (hazard ratio 0.98, 95% confidence interval 0.90-1.07, I2 = 0%), disease-free survival (HR 0.89, 95% CI 0.12-6.47, I2 = 0), or local recurrence among patients treated with Mohs surgery relative to wide excision. Quality of the evidence was very low.

CONCLUSION

This systematic review found survival and local recurrence were comparable among patients treated with Mohs surgery or wide excision for melanoma on the trunk and extremities. Future prospective contemporary studies with more diverse representation that report surgical complications and costs may facilitate more definitive recommendations.

Rates of Upstaging, Between Diagnosis and Surgery, and Clinical Management of Metastatic Cutaneous Squamous Cell Carcinoma: A Case-Control Study

BACKGROUND

Cutaneous squamous cell carcinomas (cSCC) have upstage rates of approximately 10.3% to 11.1%. Data are currently limited on the rate of upstaging for metastatic cSCC.

OBJECTIVE

The aim of this study was to determine the rates of upstaging, between diagnosis and surgery, and differences in management for metastatic and non-metastatic high-risk cSCC.

MATERIALS AND METHODS

This was a retrospective, case-control, single institution, multi-center study. Univariate analysis was used.

RESULTS

Sixty-eight subjects (34 metastatic & 34 non-metastatic) with 69 tumors were included. The overall rate of upstaging was 46.4%. The most common reasons for upstage were undocumented tumor size and under-diagnosis of poor differentiation. There were no differences in rates of upstaging. Preoperative imaging was performed in 43.6% of wide local excisions (WLE) versus 3.3% of Mohs micrographic surgery (MMS; p < .001). The median days from surgery to sentinel lymph node biopsy (SLNB), or nodal dissection was shorter for WLE versus MMS (0 vs 221 days, p < .001).

CONCLUSION

Improved clinical documentation, including documenting tumor size, and the identification of pathologic risk factors, including poor differentiation and depth of invasion, are needed for proper staging. Preoperative imaging and discussion of SLNB may be beneficial for high-risk T2b and T3 tumors.

Frequency of and risk factors for incomplete surgical margins of cutaneous cancers: a retrospective study

BACKGROUND

Incomplete resection is a problem in the management of malignancies. This study is aimed to determine frequency of and risk factors for incomplete surgical margins in skin cancers.

METHODS

In this retrospective study, resected skin cancers of a hospital from 2009 to 2020 were reviewed and, based on histopathology reports, categorized as incomplete/positive or complete/negative margins. The demographics and tumor characteristics were extracted from patients' medical files and compared between two groups.

RESULTS

Three hundred and sixty-four skin cancers were resected from 304 patients; incomplete margins occurred in 26.3%. There were no significant differences in gender, age, and site of tumors on the body parts (including head, neck, trunk, and limbs) between the positive and negative margin groups. Incomplete resections were significantly associated with size, site of tumors on various parts of the head (such as scalp, ear, nose, etc.), number of lesions excised in one session, and physician specialty.

CONCLUSIONS

Size, site of tumors on various parts of the head (such as scalp, ear, nose, etc.), number of lesions excised in one session, and physician specialty are risk factors for positive surgical margin. These characteristics may help clinicians to identify high-risk tumors and reduce the chance of incomplete cancer resection.

Neuroimmune Regulation of Surgery-Associated Metastases

Surgery remains an essential therapeutic approach for most solid malignancies. Although for more than a century accumulating clinical and experimental data have indicated that surgical procedures themselves may promote the appearance and progression of recurrent and metastatic lesions, only in recent years has renewed interest been taken in the mechanism by which metastasizing of cancer occurs following operative procedures. It is well proven now that surgery constitutes a risk factor for the promotion of pre-existing, possibly dormant micrometastases and the acceleration of new metastases through several mechanisms, including the release of neuroendocrine and stress hormones and wound healing pathway-associated immunosuppression, neovascularization, and tissue remodeling. These postoperative consequences synergistically facilitate the establishment of new metastases and the development of pre-existing micrometastases. While only in recent years the role of the peripheral nervous system has been recognized as another contributor to cancer development and metastasis, little is known about the contribution of tumor-associated neuronal and neuroglial elements in the metastatic disease related to surgical trauma and wound healing. Specifically, although numerous clinical and experimental data suggest that biopsy- and surgery-induced wound healing can promote survival and metastatic spread of residual and dormant malignant cells, the involvement of the tumor-associated neuroglial cells in the formation of metastases following tissue injury has not been well understood. Understanding the clinical significance and underlying mechanisms of neuroimmune regulation of surgery-associated metastasis will not only advance the field of neuro–immuno–oncology and contribute to basic science and translational oncology research but will also produce a strong foundation for developing novel mechanism-based therapeutic approaches that may protect patients against the oncologically adverse effects of primary tumor biopsy and excision.

Positive Margins in Cutaneous Melanoma of the Head and Neck: Implications for Timing of Reconstruction

OBJECTIVE

The aim of this study is to identify clinicopathologic features associated with positive margins after surgical treatment of cutaneous melanoma of the head and neck (CMHN).

STUDY DESIGN

Retrospective cohort study.

SETTING

National Cancer Database.

METHODS

A retrospective analysis of the National Cancer Database was performed of patients diagnosed with CMHN between 2004 and 2016. Univariate and multivariate analyses examining the association of clinicopathologic features with positive margins were performed via logistic regression analysis.

RESULTS

A total of 101,560 patients met inclusion criteria. The incidence of positive margins was 5.0% (5128/101,560). Patients were significantly more likely to have positive margins with the following: increasing age (P < .001; odds ratio [OR], 1.028; 95% CI, 1.026-1.031), the lip subsite (P < .001; OR, 1.664; 95% CI, 1.286-2.154), the eyelid subsite (P < .001; OR, 2.380; 95% CI, 1.996-2.838), the face subsite (P < .001; OR, 1.215; 95% CI, 1.133-1.302), the lentigo maligna/lentigo maligna melanoma subtype (P = .019; OR, 1.099; 95% CI, 1.016-1.188), the desmoplastic subtype (P < .001; OR, 1.455; 95% CI, 1.261-1.680), the spindle cell subtype (P = .006; OR, 1.276; 95% CI, 1.073-1.516), and advanced pT classification. Patients with male sex (P < .001; OR, 0.733; 95% CI, 0.687-0.782) and without ulceration (P < .001; OR, 0.803; 95% CI, 0.736-0.876) were significantly less likely to have positive margins.

CONCLUSION

The following have been identified as clinicopathologic features associated with positive margins after surgical treatment of CMHN: increasing age, female sex, the lip subsite, the eyelid subsite, the face subsite, ulceration, the lentigo maligna/lentigo maligna melanoma subtype, the desmoplastic subtype, the spindle cell subtype, and increasing pT classification.

Long-term outcomes of Mohs micrographic surgery for invasive melanoma of the trunk and proximal portion of the extremities

BACKGROUND

Microscopic evaluation of the entire surgical margin during excision of cutaneous malignancies results in the highest rates of complete excision and lowest rates of true local scar recurrence. Few studies demonstrate the outcomes of Mohs micrographic surgery specifically for invasive melanoma of the trunk and proximal portion of the extremities.

OBJECTIVE

To evaluate the long-term efficacy of Mohs micrographic surgery for invasive melanoma of the trunk and proximal portion of the extremities, including true local scar recurrence rate, distant recurrence-free survival, and disease-specific survival.

METHODS

Prospectively collected study of 1416 cases of invasive melanoma of the trunk and proximal portion of the extremities was performed to evaluate long-term outcomes.

RESULTS

True local scar recurrences occurred in our cohort at a rate of 0.14% (2/1416), after a mean follow-up period of 75 months and were not associated with tumor depth. The rate of satellite/in-transit recurrences and the disease-specific survival stratified by tumor thickness were superior to historical control values.

LIMITATIONS

We used a nonrandomized, single institution, retrospective design.

CONCLUSIONS

Mohs micrographic surgery of primary cutaneous invasive melanoma on the trunk and proximal portion of the extremities resulted in local control of 99.86% of tumors and an overall disease-specific death rate superior to that of wide local excision.

Prognostic Significance of RAS Mutations and P53 Expression in Cutaneous Squamous Cell Carcinomas

TP53 is considered the most commonly-altered gene in cutaneous squamous cell carcinoma (cSCC). Conversely, RAS mutations have been reported in a low percentage of cSCC. The objective of our study was to evaluate the frequency of p53 expression and RAS mutations in cSCC and correlate them with clinicopathological features and patient outcome. We performed immunohistochemistry for p53 and genetic profiling for RAS mutations in a retrospective series of cSCC. The predictive value of p53 expression, RAS mutations, and clinicopathological parameters was assessed using logistic regression models. The overall frequency of RAS mutations was 9.3% (15/162), and 82.1% of the cases (133/162) had p53 overexpression. RAS mutations rate was 3.2% (1/31) of in situ cSCCs and 10.7% (14/131) of invasive cSCCs. RAS mutations were more frequently associated with an infiltrative than an expansive pattern of invasion (p = 0.046). p53 overexpression was a predictor of recurrence in the univariate analysis. Our results indicate that RAS mutations associate with features of local aggressiveness. Larger studies with more recurrent and metastatic cSCCs are necessary to further address the prognostic significance of p53 overexpression in patients’ risk stratification.

Impact of Immediate Surgical Reconstruction Following Wide Local Excision of Malignant Head and Neck Melanoma

Background

The role of surgical reconstruction following melanoma extirpation is well recognized. Although technical considerations depend on patient anatomy and surgeon preference, the optimal timing of reconstruction remains unclear. This study aims to evaluate clinical and oncologic outcomes in melanoma extirpation followed by immediate reconstruction.

Methods

We retrospectively identified patients who underwent immediate reconstruction following head and neck melanoma excision at our institution between January 2013 and December 2016. Demographic and clinical characteristics, operative variables, and outcome data were extracted.

Results

Overall, 197 patients (male 70.6%) underwent excision followed by immediate reconstruction. Of the 70 patients with a history of cutaneous malignancy, 46 (65.7%) had a prior melanoma and 26 (37.1%) had 2 or more types of skin cancers. Of the 202 lesions resected, 138 (68.3%) were invasive, whereas 64 (31.7%) were in situ. The most frequent anatomic location involved was the cheek (34.2%), followed by scalp (31.2%). Reconstruction technique varied, with 116 (57.4%) lesions repaired by adjacent tissue transfer, 24 (11.9%) by full-thickness skin graft, 23 (11.4%) by complex primary closure, 17 (8.4%) by split-thickness skin graft, and 22 (10.9%) by more than 1 technique. On postoperative pathologic assessment, 2 patients had positive margins and 5 experienced local recurrence (mean follow-up: 2.3 years). In an unadjusted bivariate analysis, history of melanoma (P = 0.015) was significantly associated with local recurrence.

Conclusions

Reconstruction at time of excision is an oncologically safe approach for the management of patients with malignant melanoma. A prior history of melanoma may be associated with local recurrence.

Comparison of surgical margins for lentigo maligna versus melanoma in situ

BACKGROUND

Multiple studies have shown a 5-mm surgical margin to be inadequate for excision of melanoma in situ. Some have suggested that a wider margin is needed only for the lentigo maligna subtype.

OBJECTIVE

To compare subclinical extension of lentigo maligna with that of melanoma in situ. The secondary objective was to investigate the effect of other factors on extent of subclinical extension.

METHODS

A prospectively collected series of noninvasive melanomas was studied. Original pathology reports were used to identify lentigo maligna and compare data for that subtype with data for the remaining melanomas in situ.

RESULTS

A total of 1506 lentigo maligna cases and 829 melanomas in situ were included. To obtain a 97% clearance rate, both lentigo maligna and melanoma in situ required a 12-mm margin on the head and neck and a 9-mm margin on the trunk and extremities. Only 79% of lentigo maligna and 83% of melanoma in situ were successfully excised with a 6-mm margin (P = .12). Local recurrence was identified in 0.26% (5 facial, 1 scalp, and 1 acral), with a mean follow-up time of 5.7 years.

LIMITATIONS

Margins less than 6 mm were not studied. The use of lentigo maligna diagnosis was not used by all dermatopathologists consistently. The degree of surrounding photodamage was not assessed.

CONCLUSION

Subclinical extension of lentigo maligna and melanoma in situ are similar. Standard surgical excision of all melanoma in situ subtypes, including lentigo maligna, should include at least 9 mm of normal-appearing skin, which is similar to the amount recommended for early invasive melanoma. Lesions on the head and neck or those with a diameter greater than 1 cm may require even wider margins and are best treated with Mohs micrographic surgery. The perception that lentigo maligna has wider subclinical extension may be related to its frequent location on the head and neck, where photodamage can camouflage the clinical border.

Modeling the binding and diffusion of receptor-targeted nanoparticles topically applied on fresh tissue specimens

Nanoparticle (NP) contrast agents targeted to cancer biomarkers are increasingly being engineered for the early detection of cancer, guidance of therapy, and monitoring of response. There have been recent efforts to topically apply biomarker-targeted NPs on tissue surfaces to image the expression of cell-surface receptors over large surface areas as a means of evaluating tumor margins to guide wide local excision surgeries. However, diffusion and nonspecific binding of the NPs present challenges for relating NP retention on the tissue surface with the expression of cancer cell receptors. Paired-agent methods that employ a secondary 'control' NP to account for these nonspecific effects can improve cancer detection. Yet these paired-agent methods introduce multidimensional complexity (with tissue staining, rinsing, imaging, and data analysis protocols all being subject to alteration), and could be greatly simplified with accurate, predictive in silico models of NP binding and diffusion. Here, we outline and validate such a model to predict the diffusion, as well as specific and nonspecific binding, of targeted and control NPs topically applied on tissue surfaces. In order to inform the model, in vitro experiments were performed to determine relevant NP diffusion and binding rate constants in tissues. The predictive capacity of the model was validated by comparing simulated distributions of various sizes of NPs in comparison with experimental results. The regression of predicted and experimentally measured concentration-depth profiles yielded  <15% error (compared to ~70% error obtained using a previous model of NP diffusion and binding).

Melanomas of the head and neck have high-local recurrence risk features and require tissue-rearranging reconstruction more commonly than basal cell carcinoma and squamous cell carcinoma: A comparison of indications for microscopic margin control prior to reconstruction in 13,664 tumors

BACKGROUND

On the basis of high-local recurrence risk features and tissue-rearranging reconstruction, consensus guidelines recommend microscopic margin control for keratinocyte carcinomas (KCs) but not for cutaneous melanoma.

OBJECTIVE

To compare high-local recurrence risk features and frequency of tissue-rearranging reconstruction for head and neck KC with those for melanoma.

METHODS

Retrospective cohort study of KC versus melanoma treated at the Hospital of the University of Pennsylvania with Mohs micrographic surgery.

RESULTS

A total of 12,189 KCs (8743 basal cell carcinomas and 3343 squamous cell carcinomas) and 1475 melanomas (1065 melanomas in situ and 410 invasive melanomas) were identified from a prospectively updated Mohs micrographic surgery database. Compared with KCs, melanomas were significantly more likely to have high-local recurrence risk features, including larger preoperative size (2.10 cm vs 1.30 cm [P < .0001]), recurrent status (5.08% vs 3.91% [P = .031]), and subclinical spread (31.73% vs 26.52% [P < .0001]). Tissue-rearranging reconstruction was significantly more common for melanoma than for KCs (44.68% vs 33.02% [P < .0001]; odds ratio, 1.98 [P < .0001]).

LIMITATIONS

This was a retrospective study, and it did not compare outcomes with those of other treatment methods, such as slow Mohs or conventional excision.

CONCLUSION

Melanomas of the head and neck have high-local recurrence risk features and require tissue-rearranging reconstruction more frequently than KCs do.

The rule of 10s versus the rule of 2s: High complication rates after conventional excision with postoperative margin assessment of specialty site versus trunk and proximal extremity melanomas

Specialty site melanomas on the head and neck, hands and feet, genitalia, and pretibial leg have higher rates of surgical complications after conventional excision with postoperative margin assessment (CE-POMA) compared with trunk and proximal extremity melanomas. The rule of 10s describes complication rates after CE-POMA of specialty site melanomas: ∼10% risk for upstaging, ∼10% risk for positive excision margins, ∼10% risk for local recurrence, and ∼10-fold increased likelihood of reconstruction with a flap or graft. Trunk and proximal extremity melanomas encounter these complications at a lower rate, according to the rule of 2s. Mohs micrographic surgery (MMS) with frozen section melanocytic immunostains (MMS-I) and slow Mohs with paraffin sections decrease complications of surgery of specialty site melanomas by detecting upstaging and confirming complete tumor removal with comprehensive microscopic margin assessment before reconstruction. This article reviews information important for counseling melanoma patients about surgical treatment options and for developing consensus guidelines with clear indications for MMS-I or slow Mohs.

Positive margins after surgical excision of locoregional cutaneous melanoma metastasis and their impact on patient outcome

For melanoma patients, surgery is a standard treatment for locoregional skin metastasis (LSM). To assess the frequency and risk factors for positive margins after excision of LSM and their impact on patient overall survival (OS) and progression-free survival (PFS). A monocentric, retrospective observational study was performed including 87 patients with LSM who had undergone surgical excision. Positive margins were found in 45% of patients after excision. After additional excision, 28% of patients still had positive margins. Interestingly, there was no difference in PFS or OS for clear margins after the first or additional excision or for margins that remained positive without additional excision. LSM size was the only identified predictive factor for positive margins. This is the first reported study investigating the frequency of, and risk factors for positive margins of cutaneous LSM, which raises the question of whether additional excision should be performed following positive margin excision.

Patients prioritize local recurrence risk over other attributes for surgical treatment of facial melanomas-Results of a stated preference survey and choice-based conjoint analysis

BACKGROUND

Surgical treatment options for facial melanomas include conventional excision with postoperative margin assessment, Mohs micrographic surgery (MMS) with immunostains (MMS-I), and slow MMS. Patient preferences for these surgical options have not been studied.

OBJECTIVES

To evaluate patient preferences for surgical treatment of facial melanoma and to determine how patients value the relative importance of different surgical attributes.

METHODS

Participants completed a 2-part study consisting of a stated preference survey and a choice-based conjoint analysis experiment.

RESULTS

Patients overwhelmingly (94.3%) rated local recurrence risk as very important and ranked it as the most important attribute of surgical treatment for facial melanoma. Via choice-based conjoint analysis, patients ranked the following surgical attributes from highest to lowest in importance: local recurrence rate, out-of-pocket cost, chance of second surgical visit, timing of reconstruction, travel time, and time in office for the procedure. Consistent with their prioritization of low local recurrence rates, more than 73% of respondents selected MMS-I or slow MMS as their preferred treatment option for a facial melanoma.

LIMITATIONS

Data were obtained from a single health system.

CONCLUSION

Patients prefer surgical treatment options that minimize risk for local recurrence. Logistics for travel and treatment have less influence on patient preferences. Most survey participants chose MMS-I to maximize local cure and convenience of care.

A Predictive Model for Primary Closure Lengths in Mohs Surgery Based on Skin Cancer Type, Dimensions, and Location

BACKGROUND

Surgical scar length is a common concern among patients undergoing Mohs micrographic surgery (MMS).

OBJECTIVE

This study evaluates 3 metrics of preoperative lesion size to determine which correlates best with primary linear closure lengths for nonmelanoma skin cancers (NMSCs) treated with MMS. This metric is then used to develop predictive models for linear closure lengths in 10 different anatomical regions.

MATERIALS AND METHODS

A retrospective study of 4,049 NMSCs treated with MMS and repaired with primary linear closure was conducted. Primary closure lengths were plotted against preoperative lesion circumference, area, and short axis length. Linear regression analysis was performed.

RESULTS

Preoperative NMSC circumference correlated best with closure length. Twenty-one of the 28 regression models had coefficients of determination (R) above 0.5. Closure lengths increased by 0.52 to 1.1 mm, depending on location, for every millimeter increase in preoperative NMSC circumference.

CONCLUSION

Preoperative lesion circumference is directly proportional to primary closure length and is a better indicator of closure length than preoperative area and short axis for MMS of NMSCs. Closure lengths located on the nasal tip, supratip, or periocular areas are most sensitive to differences in NMSC size. These data might aid Mohs surgeons with preoperative planning for wound reconstruction and patient counseling.

Outcomes of Melanoma In Situ Treated With Mohs Micrographic Surgery Compared With Wide Local Excision

Importance

Melanoma in situ (MIS) is increasing in incidence, and expert consensus opinion recommends surgical excision for therapeutic management. Currently, wide local excision (WLE) is the standard of care. However, Mohs micrographic surgery (MMS) is now used to treat a growing subset of individuals with MIS. During MMS, unlike WLE, the entire cutaneous surgical margin is evaluated intraoperatively for tumor cells.

Objective

To assess the outcomes of patients with MIS treated with MMS compared with those treated with WLE.

Design, Setting, and Participants

Retrospective review of a prospective database. The study cohort consisted of 662 patients with MIS treated with MMS or WLE per standard of care in dermatology and surgery (general surgery, otolaryngology, plastics, oculoplastics, surgical oncology) at an academic tertiary care referral center from January 1, 1978, to December 31, 2013, with follow-up through 2015.

Exposure

Mohs micrographic surgery or WLE.

Main Outcomes and Measures

Recurrence, overall survival, and melanoma-specific survival.

Results

There were 277 patients treated with MMS (mean [SD] age, 64.0 [13.1] years; 62.1% male) and 385 treated with WLE (mean [SD] age, 58.5 [15.6] years; P < .001 for age; 54.8% male). Median follow-up was 8.6 (range, 0.2-37) years. Compared with WLE, MMS was used more frequently on the face (222 [80.2%] vs 141 [36.7%]) and scalp and neck (23 [8.3%] vs 26 [6.8%]; P < .001). The median (range) year of diagnosis was 2008 (1986-2013) for the MMS group vs 2003 (1978-2013) for the WLE group (P < .001). Overall recurrence rates were 5 (1.8%) in the MMS group and 22 (5.7%) in the WLE group (P = .07). Mean (SD) time to recurrence after MMS was 3.91 (4.4) years, and after WLE, 4.45 (2.7) years (P = .73). The 5-year recurrence rate was 1.1% in the MMS group and 4.1% in the WLE group (P = .07). For WLE-treated tumors, the surgical margin taken was greater for tumors that recurred compared with tumors that did not recur (P = .003). Five-year overall survival for MMS was 92% and for WLE was 94% (P = .28). Melanoma-specific mortality for the MMS group was 2 vs 13 patients for the WLE group, with mean (SD) survival of 6.5 (4.8) and 6.1 (0.8) years, respectively (P = .77).

Conclusions and Relevance

No significant differences were found in the recurrence rate, overall survival, or melanoma-specific survival of patients with MIS treated with MMS compared with WLE.

Clinical and pathologic factors associated with subclinical spread of invasive melanoma

BACKGROUND

Indications to treat invasive melanoma with Mohs micrographic surgery (MMS) or analogous techniques with exhaustive microscopic margin assessment have not been defined.

OBJECTIVE

Identify clinical and histologic factors associated with subclinical spread of invasive melanoma.

METHODS

This retrospective, cross-sectional study evaluated 216 invasive melanomas treated with MMS and melanoma antigen recognized by T cells 1 immunostaining. Logistic regression models were used to correlate clinicopathologic risk factors with subclinical spread and construct a count prediction model.

RESULTS

Risk factors associated with subclinical spread by multivariate analysis included tumor localization on the head and neck (OR 3.28, 95% confidence interval [CI] 1.16-9.32), history of previous treatment (OR 4.18, 95% CI 1.42-12.32), age ≥65 (OR 4.45, 95% CI 1.29-15.39), and ≥1 mitoses/mm2 (OR 2.63, 95% CI 1.01-6.83). Tumor thickness and histologic subtype were not associated with subclinical spread. The probability of subclinical spread increased per number of risk factors, ranging from 9.22% (95% CI 2.57%-15.86%) with 1 factor to 80.32% (95% CI 68.13%-92.51%) with 5 factors.

LIMITATIONS

This study was conducted at a single academic institution with a small study population using a retrospective study design that was subject to potential referral bias.

CONCLUSION

Clinical and histologic factors identify invasive melanomas that are at increased risk for subclinical spread and might benefit from MMS or analogous techniques prior to reconstruction.