BACKGROUNDOne of the most notable applications for circulating tumor DNA (ctDNA) detection in peripheral blood of patients with metastatic colorectal cancer (mCRC) is a long-term postoperative follow-up. Sometimes referred to as a “liquid (re)biopsy” it is a minimally invasive procedure and can be performed repeatedly at relatively short intervals (months or even weeks). The presence of the disease and the actual extent of the tumor burden (tumor mass) within the patient’s body can be monitored. This is of particular importance, especially when evaluating radicality of surgical treatment as well as for early detection of disease progression or recurrence.AIMTo confirm the radicality of surgery using ctDNA and compare available methods for detection of recurrence in metastatic colorectal cancer.METHODSA total of 47 patients with detected ctDNA and indications for resection of mCRC were enrolled in the multicenter study involving three surgical centers. Standard postoperative follow-ups using imaging techniques and the determination of tumor markers were supplemented by ctDNA sampling. In addition to the baseline ctDNA testing prior to surgery, a postoperative observation was conducted by evaluating ctDNA presence up to a week after surgery and subsequently at approximately three-month intervals. The presence of ctDNA was correlated with radicality of surgical treatment and the actual clinical status of the patient.RESULTSAmong the monitored patients, the R0 (curative) resection correlated with postoperative ctDNA negativity in 26 out of 28 cases of surgical procedures (26/28, 93%). In the remaining cases of R0 surgeries that displayed ctDNA, both patients were diagnosed with a recurrence of the disease after 6 months. In 7 patients who underwent an R1 resection, 4 ctDNA positivities (4/7, 57%) were detected after surgery and associated with the confirmation of early disease recurrence (after 3 to 7 months). All 15 patients (15/15, 100%) undergoing R2 resection remained constantly ctDNA positive during the entire follow-up period. In 22 cases of recurrence, ctDNA positivity was detected 22 times (22/22, 100%) compared to 16 positives (16/22, 73%) by imaging methods and 15 cases (15/22, 68%) of elevated tumor markers.CONCLUSIONctDNA detection in patients with mCRC is a viable tool for early detection of disease recurrence as well as for confirmation of the radicality of surgical treatment.

Sentinel node biopsy in gastric cancer using vital staining is a feasible method. Reliable results were seen in early stage of the disease. Fresh frozen section of sentinel node has probably a low sensitivity for detection of micrometastases.

Maligní mezoteliom je vysoce maligní onemocnění. Objevuje se nejčastěji na serózách pleury, dále na peritoneu, perikardu a tunice vaginalis varlete. Peritoneální varianta (MPM) zahrnuje 10-15 % všech mezoteliomů. Prokázaným rizikovým faktorem je expozice azbestu. Symp tomatologie není specifická, dia gnosticky se uplatňují zobrazovací metody (počítačová tomo grafie) a bio ptické vyšetření. Dosud neexistují žádná všeobecně uznávaná doporučení radikální léčby MPM. V minulosti byla prognóza pa cientů s mezoteliomem špatná, přežívání bylo do 1 roku. V dnešní době, pokud je pa cient vhodným kandidátem radikální kombinované léčby, se medián přežívání pohybuje mezi 3 a 5 lety. U vybraných pa cientů je doporučována kombino vaná léčba cytoredukční chirurgií (CRS) a hypertermickou perioperační chemoterapií (HIPEC), chemoterapie samotná vykazuje nedostatečnou účinnost. Obecně by měli být k radikálnímu řešení indikováni pa cienti s difuzní formou MPM, bez extraperitoneálních ložisek, v dobrém cel kovém stavu, takoví, u nichž předpokládáme dosažení maximální cytoredukce. Systémová che moterapie zůstává jedinou léčebnou možností u pa cientů, kteří nemohou být indikováni k CRS a HIPEC. U vybraných pa cientů plánovaných nebo podstupujících CRS a HIPEC může být tento přístup kombinovaný se systémovou chemoterapií v neoadjuvantním nebo adjuvantním po dání, nicméně jejich přínos není jasný. Dosud neexistují žádná doporučení týkající se sledování pa cientů s MPM po radikálním operačním výkonu. Vzhledem k absenci specifických sérových markerů lze doporučit z běžně dostupných jen CA 125 a mezotelin. Ze zobrazovacích metod pak ultrazvuk břicha, počítačovou tomografii břicha a malé pánve či magnetickou rezonanci. Klíčová slova mezoteliom-cytoredukční chirurgie-intraperitoneální chemoterapie Summary Malignant mesothelioma is a highly malignant disease that most often occurs in the pleura of the thoracic cavity, followed by the peritoneum, pericardium, or tinea vaginalis testis. Malignant peritoneal mesothelioma (MPM) accounts for 10-15% of all mesotheliomas. The most significant risk factor for MPM is exposure to asbestos. There is no specific symptomatology, and imaging (computed tomography) and histopathology are crucial for diagnosis. There are no generally accepted guidelines for radical treatment of MPM. Previously, the prognosis of MPM patients was poor, with survival of up to 1 year. However, median survival of patients who are suitable candidates for radical therapy is currently 3-5 years. A combination of cytoreductive surgery (CRS) and hyperthermic perioperative chemotherapy (HIPEC) is recommended in selected patients, while chemotherapy alone has insufficient efficacy. Systemic chemotherapy remains the only treatment option for patients who are unsuitable for CRS and HIPEC. In selected patients scheduled for or currently undergoing CRS and HIPEC, surgery may be performed in combination with systemic chemotherapy in the neoadjuvant or adjuvant setting; however, the benefit is unclear. There are no recommendations for followup o...

Gastric cancer usually affects people older than sixty years. This type of cancer is very rare in adults under thirty years of age. In addition, the prognosis in this part of population is grave due to the high incidence of undifferentiated tumours and advanced stage at time of diagnosis. Radical surgery affords the only chance for long term survival, but even this option is often limited upon finding locally advanced disease or peritoneal seeding. The following are case studies of three young adults from a group of 45 patients, who were treated between January 1st, 2000 and December 31st, 2003.