The Swiss equivalent of the Polish medical title lekarz is Arzt/Ärztin. You need to get it before you can practise medicine in Switzerland. This is permitted after your Polish medical diploma (lekarz) is recognized as equivalent to a Swiss diploma by the Medical Professions Commission (MEBEKO), Department of Education, in the Federal Office of Public Health (BAG).

Upon my inquiry, a lawyer from the Federal Office of Public Health told me that for the recognition process, they look at the Polish medical degree called "Dyplom ukończenia studiów wyższych na kierunku lekarskim z tytułem „lekarza“", and added that everything they do is in accordance with the EU Directive 2005/36 and the Free Movement Agreement between the EU and Switzerland. 

Monika Korenkiewicz from our Dean's Office told me that the aforementioned diploma is received after finishing all 6th year exams, within 30 days from the date of the last exam, LEK and Staz independent. 

Consequently, in order to become Arzt/Ärztin in Switzerland, the university's graduation diploma and a certificate from the Center for Medical Examinations (meaning taking and passing the LEK) is required.

For a deepdive into your career steps – recognition problem aside – I want to recommend using the recourses from FMH and SIWF (https://www.siwf.ch/index.cfm#), the swiss-wide organisation for medical training and specialists. For example, with their website, you can easily find and filter all available hospitals in Switzerland that offer training in your field of interest. The website is officially available in German, Italian, or French; one of which you should be able to speak if you want to work in Switzerland. 

You have to complete all steps of the application form "Antragsformular: Direkte Anerkennung eines Diploms", and send it together with all the other required documents to this postbox: 

The processing fee will cost somewhere between 800 to 1000 CHF and is sent to you via invoice after they received and verified your documents. 

Once they received the money, they will send you a document confirming recognition and qualification, granting you to start applying/working as a Arzt/Ärztin in Switzerland! 

The above mentioned application form must be accompanied by: *

• a copy of the identity card, and – if this results from the form – copies of the wife's/ husband's ID card and the marriage certificate

• professional resume (CV) 

• a copy of the diploma of completion of higher education in the field of medicine with the title "Lekarz" at a Polish university and a certificate of the Center for Medical Examinations certifying a positive result from the Medical Final Exam or the Medical State Exam.

• originals or certified copies of the above diplomas and certificates translated into German, French, Italian or English.

• proof of knowledge of one of the official languages of Switzerland (German, French, Italian) at least B2 (on the European scale of knowledge in foreign languages).

The authenticity of a copy can be certified by a notary, local authority official, court, consulate or embassy (from EU/EFTA member states or Switzerland). All Polish documents should be translated by a professional sworn translator. For details on translations, see the Swiss Association of Translators, Terminologists and Interpreters (ASTTI).

If you seek support before starting your process, I can personally recommend emailing your questions to the BAG (Public Health Office) directly.  They are the responsible health authority, and I would say that nobody else will know better than them. I received my answers from a lawyer of theirs only a day after (!).

In my case, the email I used was info@bag.admin.ch, and a resonse came from MEBEKO@bag.admin.ch. 

If your questions are more general in nature, or you just want to read about Switzerland as an option, definitely check out this subreddit: https://www.reddit.com/r/medicalschoolEU/wiki/index/switzerland/.

Good luck!