The Effect of Time to Postoperative Radiation Therapy on Survival in Resected Merkel Cell Carcinoma

Increased risk of recurrence and disease-specific death following delayed postoperative radiation for Merkel cell carcinoma

BACKGROUND

Merkel cell carcinoma (MCC) is often treated with surgery and postoperative radiation therapy (PORT). The optimal time to initiate PORT (Time-to-PORT [ttPORT]) is unknown.

PURPOSE

We assessed if delays in ttPORT were associated with inferior outcomes.

METHODS

Competing risk regression was used to evaluate associations between ttPORT and locoregional recurrence (LRR) for patients with stage I/II MCC in a prospective registry and adjust for covariates. Distant metastasis and death were competing risks.

RESULTS

The cohort included 124 patients with median ttPORT of 41 days (range: 8-125 days). Median follow-up was 55 months. 17 (14%) patients experienced a LRR, 14 (82%) of which arose outside the radiation field. LRR at 5 years was increased for ttPORT >8 weeks vs ≤ 8 weeks, 28.0% vs 9.2%, P = .006. There was an increase in the cumulative incidence of MCC-specific death with increasing ttPORT (HR = 1.14 per 1-week increase, P = .016).

LIMITATIONS

The relatively low number of LRRs limited the extent of our multivariable analyses.

CONCLUSIONS

Delay of PORT was associated with increased LRR, usually beyond the radiation field. This is consistent with the tendency of MCC to spread quickly via lymphatics. Initiation of PORT within 8 weeks was associated with improved locoregional control and MCC-specific survival.

Delayed time to radiation and overall survival in Merkel cell carcinoma

BACKGROUND

Clinically localized Merkel cell carcinoma (MCC) is commonly treated with surgical excision and radiotherapy. The relationship between time to adjuvant radiotherapy and overall survival (OS) remains understudied.

METHODS

This retrospective study used data from the National Cancer Database (2006-2019). Patients with clinically localized MCC who received surgical excision and adjuvant radiotherapy were included. Multivariate regressions were used to account for various patient and tumor factors. The primary outcome was 5-year OS, and the secondary outcome was time from diagnosis to adjuvant radiation (TTR).

RESULTS

Of the 1965 patients included, most were male (n = 1242, 63.2%) and white (n = 1915, 97.5%), and the median age was 74 years (interquartile range [IQR]: 66-81). The median TTR was 83 days (IQR: 65-106). A total of 83.6% of patients received radiotherapy to the primary site, 21.3% to the draining nodal basin, 17.1% to both, and 12.2% whose target location of radiotherapy was not recorded in the data. TTR of ≥79 days (the 45th percentile) was associated with worse OS on both univariate and multivariate analyses (log-rank p = 0.0014; hazard ratio [HR]: 1.258, 95% confidence interval [CI]: 1.055-1.500, p = 0.010). This persisted on sub-analyses of patients <80 years old (n = 1407; HR: 1.380, 95% CI: 1.080-1.764, p = 0.010) and of patients with Charlson comorbidity index (CCI) of 0 (n = 1411; HR: 1.284, 95% CI: 1.034-1.595, p = 0.024). Factors associated with delayed TTR included greater age (p = 0.039), male sex (p = 0.04), CCI > 1 (p = 0.036), academic facility (p < 0.001), rural county (p = 0.034), AJCC T2 stage (p = 0.010), negative margins (p = 0.017), 2+ pathologically positive regional nodes (p = 0.011), and margin size >2 cm (p = 0.015).

CONCLUSIONS

Delayed radiotherapy (≥79 days) was associated with worse OS of MCC patients. Further study in controlled cohorts is needed to ascertain this relationship.

Merkel Cell Carcinoma: An Immunotherapy Fairy-Tale?

Merkel cell carcinoma (MCC) is a rare, highly aggressive, neuroendocrine cutaneous tumor. The incidence of MCC is growing worldwide, and the disease-related mortality is about three-fold higher than melanoma. Since a few years ago, very little has been known about this disease, and chemotherapy has been the standard of care. Nowadays, new discoveries about the pathophysiology of this neoplasm and the introduction of immunotherapy allowed to completely rewrite the history of these patients. In this review, we provide a summary of the most important changes in the management of Merkel cell carcinoma, with a focus on immunotherapy and a landscape of future treatment strategies.

Systematic literature review of current treatments for stage I-III Merkel cell carcinoma

Aim: There is a need to evaluate current treatments for stages I-III of Merkel cell carcinoma (MCC). Materials & methods: A systematic literature review was conducted to understand how patients with stage I-III MCC are treated and assess efficacy, safety, health-related quality of life and economic impact of current therapies. Embase was searched using the following inclusion criteria: publications from 2014 to 2019, in English, with adult patients (≥18 years) with early-stage MCC (i.e., stages I-III) and any interventions/comparators. Publications were excluded if they included only patients with stage IV MCC, had no distinction between early and advanced or metastatic MCC or had no extractable data. Results: A total of 18 retrospective studies were included. Few studies had evidence that surgery plus adjuvant radiotherapy significantly increased survival versus surgery alone in early MCC. Limited safety data were reported in three studies. None of the studies reported data on health-related quality of life or economic impact of treatment in patients with early-stage MCC. Conclusion: Although surgery plus adjuvant radiotherapy was a common treatment, no clear standard of care exists for stages I-III MCC and treatment outcomes need to be improved. All studies were retrospective with a high variability in sample sizes; hence, findings should be interpreted with caution.

Merkel Cell Carcinoma of the Head and Neck: Epidemiology, Pathogenesis, Current State of Treatment and Future Directions

Merkel cell carcinoma (MCC) is a rare, cutaneous neuroendocrine malignancy with increasing incidence. The skin of the head and neck is a common subsite for MCC with distinctions in management from other anatomic areas. Given the rapid pace of developments regarding MCC pathogenesis (Merkel cell polyoma virus (MCPyV)-positive or virus-negative, cell of origin), diagnosis, staging and treatment, and up to date recommendations are critical for optimizing outcomes. This review aims to summarize currently available literature for MCC of the head and neck. The authors reviewed current literature, including international guidelines regarding MCC pathogenesis, epidemiology, diagnosis, staging, and treatment. Subsequently recommendations were derived including the importance of baseline imaging, MCPyV serology testing, primary site surgery, nodal evaluation, radiotherapy, and the increasing role of immune modulating agents in MCC. MCPyV serology testing is increasingly important with potential distinctions in treatment response and surveillance between virus-positive and virus-negative MCC. Surgical management continues to balance optimizing local control with minimal morbidity. Similarly, radiotherapy continues to have importance in the adjuvant, definitive, and palliative setting for MCC of the head and neck. Immunotherapy has changed the paradigm for advanced MCC, with increasing work focusing on optimizing outcomes for non-responders and high-risk patients, including those with immunosuppression.

Surgical Management of Merkel Cell Carcinoma

The incidence of Merkel cell carcinoma (MCC) continues to increase. Understanding of MCC biology has advanced rapidly, with current staging providing valuable prognostic information. MCC treatment often is multidisciplinary. Surgery remains an important component in the staging and treatment, most commonly involving wide excision of the cancer and sentinel lymph node biopsy. Lymphadenectomy is used to treat nodal disease. Radiotherapy enhances locoregional control and possibly survival. Systemic therapies, in particular novel immunotherapies, may be promising in the treatment of advanced or recurrent and metastatic disease.

Impact of induction chemotherapy and socioeconomics on sinonasal undifferentiated carcinoma survival

BACKGROUND

Sinonasal undifferentiated carcinoma (SNUC) is an uncommon malignancy of the nasal cavity and accessory sinuses with limited available studies evaluating role of induction chemotherapy (IC), demographics, and socioeconomic factors on overall survival (OS).

METHODS

The 2004-2015 National Cancer Database was queried for patients with histologically confirmed SNUC. IC was defined as chemotherapy administered 6 months to 2 weeks before surgery or ≥45 days before radiotherapy.

RESULTS

Of 440 identified patients, 70 (16%) underwent treatments involving IC. This consisted of 52 (12%), 15 (3%), and 3 (1%) patients receiving IC before definitive radiation therapy, surgery and adjuvant radiotherapy, or surgery only, respectively. On univariate analysis, IC (p = 0.34) did not affect OS, whereas having government insurance (hazard ratio [HR], 1.79; 95% confidence interval [CI], 1.37-2.34; p < 0.001) and living in regions with ≥13% of the population without a high school diploma (HR, 1.38; 95% CI, 1.06-1.79; p = 0.02) were associated with worse OS. On log-rank test, patients with advanced stage had similar OS regardless of whether or not they received IC (p = 0.96). Patients who received IC lived closer to their treatment site (p = 0.02) and had worse overall health, with more comorbidities (p = 0.02). The timing of IC before definitive surgery or radiation did not affect OS (p = 0.69).

CONCLUSION

In this SNUC population-based analysis, IC did not appear to provide additional OS benefit regardless of disease stage or timing before definitive treatment. Distance to treatment and level of comorbidities may be associated with receiving IC, whereas type of insurance and residence education level may impact SNUC OS, regardless of treatment.