Table I.
Clinical findings of Merkel cell carcinoma with lymph node metastasis in absent of a primary site.
| First author (Ref.) | Case no. | Age (years) | Gender | Site | Histol. type | Skin site of primary | Local recur. (months) | Extraregio. or distant spread (months) | Treatment | Follow-up (months) |
|---|---|---|---|---|---|---|---|---|---|---|
| Kaplan et al (12) | 1 | Elderly | M | Axilla LN, L and R Cervical LN, R |
S | UK | UK | Brain, liver and adrenal gland, syn. | RT | DOD (4) |
| Pilotti et al (13) | 2 | 50 | M | Inguinal LN, R | D | UK | UK | Retroperit. and pancreas, syn. | RT | ED 6) |
| 3 | 58 | M | Inguinal LN, R | S | UK | UK | UK | SE | NED (5) | |
| 4 | 65 | M | Inguinal LN, R | S | UK | UK | UK | SE | NED (18) | |
| 5 | 73 | M | Inguinal LN, R | S | UK | UK | UK | SE | ED (36) | |
| 6 | 66 | M | Inguinal LN, R | D | UK | UK | UK | SE | DOC (168) | |
| 7 | 65 | F | Inguinal LN, R | T | UK | UK | UK | UK | Cons | |
| 8 | 39 | F | Inguinal LN, R | S | UK | UK | UK | SE | Cons | |
| 9 | 53 | F | Inguinal LN, L | S | UK | 6 | UK | SE | NED (8) | |
| 10 | 78 | M | Inguinal LN, L | D | UK | UK | Supraclav. LN, L (48) | CT | DOD (60) | |
| 11 | 52 | F | Axilla LN, R | D | UK | UK | UK | SE | NED (30) | |
| Eusebi et al (14) | 12 | 65 | F | Axilla LN, L | UK | UK | UK | UK | RT+CT | NED (6) |
| 13 | 46 | M | Inguinal LN, L | UK | UK | UK | UK | UK | NED (10) | |
| 14 | 37 | M | Inguinal LN, R | UK | UK | 6 | Pelvic LN, R (12) Cervical LN, R (15) |
RT+CT | DOD (25) | |
| 15 | 46 | F | Inguinal LN, L | UK | UK | UK | UK | UK | NED (19) | |
| 16 | 64 | M | Inguinal LN, L | UK | UK | 11 | UK | UK | NED (25) | |
| 17 | 68 | F | Inguinal LN, L | UK | UK | UK | Paraortic LN, R (3) Parailliac LN, L (3) |
UK | DOD (8) | |
| 18 | 80 | F | Submandibular LN, L | UK | UK | UK | UK | UK | NED (26) | |
| 19 | 54 | F | Inguinal LN, L | UK | UK | 5 | Iliac LN, L (12) | RT+CT | ED (12) | |
| Rice et al (15) | 20 | 76 | M | Upper jugular area LN, R | S | UK | UK | UK | SE+RT | NED (23) |
| Yang et al (16) | 21 | 74 | M | Neck LN, R | UK | UK | UK | Submandibular gland, syn. | SE+RT | DOD (12) |
| Straka and Straka (17) | 22 | 71 | F | Neck LN in zone II, R | UK | UK | 10 | Submandibular gland, syn. brain (10) | SE+RT+CT | DOD (12) |
| 23 | 52 | M | Inguinal LN, L | S | UK | UK | UK | SE+CT | UK | |
| Zhao and Meng (TS) | 24 | 54 | M | Inguinal LN, R | S | Dorsi-thigh, R | UK | Vertebrae (1) Humerus and liver (12) |
SE+RT+CT | DOD (21) |
TS, this study; F, female; M, male; axilla, axillary; LN, lymph node; R, right; L, left; histol, histological; S, solid; D, diffuse; T, trabecular; UK, unknown; recur, recurrence; extraregio, extraregional; syn, synchronous; supraclav, supraclavicular; RT, radiotherapy; SE, surgical excision; CT, chemotherapy; DOD, died of disease; ED, evidence of disease; NED, no evidence of disease; DOC, died of other disease; cons, consultation case.