Management of cancers of unknown origin is complex. When the primary site is not identified and when it does not fall neatly into certain specific clinical patterns, empiric broad-spectrum chemotherapy is recommended by NCCN and is generally acceptable. The issue remains second line chemotherapy for adenocarcinooma of occult primary. Combination sequential chemotherapy with paclitaxel, carboplatin, and oral etoposide followed by gemcitabine and irinotecan proved to be an active and useful therapy for some patients with unknown primary carcinomas. I reviewed the literature and found several phase II trials of second line chemotherapy but not with this regimen. For example, on ongoing trial is a phase II trial, to evaluate the feasibility and efficacy of the oxaliplatin/capecitabine combination in patients who have had one previous chemotherapy regimen for the treatment of carcinoma of unknown primary site. Gemcitabine, an active drug in several solid tumors, has also found to be useful as secondary therapy for some patients with carcinoma of unknown primary site. Phase II trials of gemcitabine and topotecan in second-line therapy of unknown primary cancer are underway. Still, no phase III trials and no guidelines recommandations could be located.
Greco, F. Anthony , Rodriguez, Gladys I. , Shaffer, Don W. , Hermann, Robert , Litchy, Sharlene , Yardley, Denise A. , Burris, Howard A., III , Morrissey, Lisa H. , Erland, Joan B. , Hainsworth, John D. Carcinoma of Unknown Primary Site: Sequential Treatment with Paclitaxel/Carboplatin/Etoposide and Gemcitabine/Irinotecan: A Minnie Pearl Cancer Research Network Phase II Trial Oncologist 2004 9: 644-652;
F. Anthony Greco et al, Carcinoma of Unknown Primary Site: Sequential Treatment with Paclitaxel/Carboplatin/Etoposide and Gemcitabine/Irinotecan: A Minnie Pearl Cancer Research Network Phase II Trial The Oncologist, Vol. 9, No. 6, 644-652, November 2004;
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K. Fizazi et al, Cancers of unknown primary site: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up, Ann Oncol (2011) 22 (suppl 6): vi64-vi68.