Table 2.
Patient and therapy parameter, tumor characteristics, and follow-up data
| Patient 1 | Patient 2 | Patient 3 | Patient 4 | Patient 5 | Patient 6 | |
|---|---|---|---|---|---|---|
| Age (years) | 66 | 63 | 54 | 67 | 73 | 68 |
| Gender | Male | Male | Female | Female | Female | Female |
| Diagnosis before abdominoperineal resection | ||||||
| S100 protein in serum (normal range < 0.1 μg/l) | 0.079 | 0.301 | 0.049 | 0.199 | 0.039 | 0.050 |
| Preoperative biopsy | – | Yes | – | Yes | – | Yes |
| Previous local excision | Yes | – | Yes | – | Yes | |
| Therapy | ||||||
| Type of abdominoperineal resection (APR) | APR | ELAPR | ELAPR | ELAPR | lap. ELAPR | lap. ELAPR |
| Intention for abdominoperineal resection | Curative | Palliative | Curative | Palliative | Palliative | Curative |
| Time interval between diagnosis and APR (months) | 3 | 1 | 3 | 2 | 13 | 2 |
| Adjuvant/additive therapy | – | DTIC | 1. Ipilimumab | DTIC | 1. Radiation | Ipilimumab (1 cycle) |
| 2. Nivolumab | 2. DTIC | |||||
| 3. Ipilimumab | ||||||
| Tumor characteristics, histopathology/immunostaining | ||||||
| Tumor stage | I | IV | II | IV | III | III |
| Tumor localization referring to the dentate line | Above DL | Overlapping zones | On and above DL (multifocal) | DL | DL | Above DL |
| Tumor diameter (cm) | 0.9 | 11 | 0.5 + 0.4 + 0.4 | 10.5 | <1 | 10,9 |
| Depth of infiltration (mm) | <3 | 15 | 4 | All layers | 3 | All layers |
| Negative resection margin (R0) | Yes | Yes (<1 mm) | Yes | Yes | Yes (marginal) | Yes |
| Amelanotic melanoma | Yes | No | No | Yes | No | No |
| S100 protein | – | – | – | Positive | – | Positive |
| Melan-A | – | Positive | – | Positive | – | Positive |
| Mutation analysis | ||||||
| KIT | – | Wild–type | Wild–type | Wild–type | Wild–type | Wild–type |
| BRAF | – | – | Wild–type | Wild–type | Wild–type | Wild–type |
| NRAS | – | – | Wild–type | Wild–type | – | Wild–type |
| Follow up (months) | 102 | 6 | 60 | 10 | 18 | 18 |
| Local recurrence | No | Yes | No | No | Yes | No |
| Time interval to abdominoperineal resection (months) | – | 1 | – | – | 3 | – |
| Metachronous lymph node metastasis | No | ns | Yes | Yes | Yes | No |
| Mediastinum | – | – | Yes | Yes | – | – |
| Perirectal | – | – | – | – | yes | – |
| Time interval to abdominoperineal resection (months) | – | – | 42 | 3 | 5 | – |
| Metachronous distant metastasis | No | ns | Yes | Yes | Yes | No |
| Lung/pleura | – | ns | Yes | – | Yes | No |
| Liver | – | – | No | Yes | Yes | No |
| Peritoneum | – | ns | No | No | Yes | No |
| Bone | – | ns | No | No | Yes | No |
| Soft tissue | – | ns | No | No | Yes | No |
| Brain | – | ns | No | No | Yes | No |
| Time interval to abdominoperineal resection (months) | – | – | 21 | 3 | 12 | – |
| Health status at follow-up time interval to abdominoperineal resection (months) | Disease-free | Dead 6 | Slowly progressive disease | Dead 10 | Dead 18 | Disease-free |
Before surgery, elevated serum levels of S-100 were measured only in patients with distant metastasis (stage IV). In all patients, the tumor origin was on or slightly above the dentate line. In patient 2, the tumor invades the anal canal. And, in patient 3, the ARMM was found at several localizations around the dentate line. During the first surgery, clear resection margins (R0) were achieved in all six patients. In patients 2 and 5, the resection margins were just barely R0. In patient 5, primarily, a local excision was performed. While in this patient multiple local recurrences were removed by local procedures over a time period of several months, also an LNM in the mesorectum was detected in the course. Consequently, laparoscopic extralevator abdominoperineal resection was carried out for local control. However, at this time, the tumor mass was not removable in total (R1). Patient 3 shows an atypical course of ARMM with a slowly progressive disease for more than 5 years
APR abdominoperineal resection, ELAPR extralevator abdominoperineal resection, lap. ELAPR laparoscopic extralevator abdominoperineal resection, DTIC dacarbacin, DL dentate line, ns not specified