The Importance of the Head and Neck Region in Regression of Advanced MCC

Case of probable spontaneous regression of Merkel cell carcinoma combined with squamous cell carcinoma without surgical intervention

Merkel cell carcinoma (MCC) is a rare but more lethal cutaneous cancer than melanoma. However, spontaneous regression of a number of MCC has been reported, although the cause of this regression remains unclear. In most cases, MCC regresses after a surgical procedure, for example, biopsy. Herein, we report a case of Merkel cell polyomavirus-negative MCC coincident with squamous cell carcinoma (SCC) that underwent true spontaneous regression without biopsy. One month after the patient's first visit, clinical examination revealed that the tumor had not grown, but its surface showed changes in texture and color. Histopathologically, the excised specimen was indicative of MCC coincident with SCC and showed extensive necrosis in the upper portion of the tumor, numerous caspase-3-positive apoptotic cells, an accumulation of CD68-positive foam cells and vascular invasion. These findings suggested that the tumor had regressed. We hypothesize that extensive coagulative necrosis resulting from an insufficient local blood supply triggered the shedding of some products or components of MCC and SCC, which in turn induced antitumor immunity against both lesions.

Meta-analysis of regression of advanced solid tumors in patients receiving placebo or no anti-cancer therapy in prospective trials

BACKGROUND

A meta-analysis of prospective trials systematically investigated regression of advanced solid tumors in patients receiving placebo or no anticancer therapy to inform on spontaneous regressions.

PATIENT AND METHODS

Arms of randomized controlled trials (RCTs) of metastatic solid tumors receiving placebo or no anti-cancer therapy were used. Statistical analyses were conducted to calculate the overall response rate (ORR) and to detect differentials based on histology, progression at baseline and prior therapies.

RESULTS

A total of 7676 patients were evaluable from 61 RCTs evaluating 18 solid tumors. The ORR was 1.95% (95% CI: 1.52-2.48%). There was no significant effect of histology (p=0.110), baseline progressive disease (p>0.20) or the line of therapy (p>0.20) on ORR.

CONCLUSIONS

Spontaneous regressions are seen across all advanced solid tumors. Some malignancies demonstrated higher rates of spontaneous regressions and may be relatively immunotherapy responsive.

Spontaneous regression of Merkel cell carcinoma of the nose

BACKGROUND

Merkel Cell Carcinoma (MCC) is a rare neurendocrine tumor of cutaneous origin.

METHODS AND RESULTS

A 79-year-old woman was seen with a neck lump and a lesion in the left nasal vestibule. Biopsy of the lesion revealed a primary neurendocrine MCC of the skin of the nasal vestibule with metastases to the cervical lymph nodes. The patient decided against any further active treatment. Follow-up of patient for 30 months showed spontaneous regression of the lesions without any active treatment.

CONCLUSIONS

Although spontaneous resolution of MCC has been described for other head neck sites, there has not been any published case of nasal MCC regression. We present this rare case of nasal MCC with neck metastases and its regression.