Mars is a highly powerful and energetic planet that signifies strength, courage, and passion. When placed in the 8th house for lagna Cancer, Mars brings about significant changes and transformations in life. This placement of Mars in the neutral sign state indicates that its influence on the native's life would be moderate.
As Mars is the lord of houses 5 and 10, its placement in the 8th house implies that these houses would also receive considerable attention. The fifth house pertains to education, creativity, love affairs, and children while the tenth house signifies one's profession, career, status, and reputation. With Mars influencing both these houses through its placement in the 8th house, there could be sudden upheavals or changes in these areas of life.
However, due to its neutral sign state placement, Mars does not cause any serious harm but rather brings about positive growth and development in these domains. Those who are into creative fields such as art or music may witness their work receiving accolades and recognition because of Mars' influence on the 5th house.
Meanwhile, individuals with a career may get promotion or new job opportunities that enhance their work profile's prestige because of Mars' impact on the tenth house.
Mars being a natural karaka of houses 3 (siblings) & 6 (enemies), it also takes care of its own karaka houses when placed in the 8th for cancer ascendants. There may be some conflicts with siblings or enemies at times as a result of its positioning here. But overall it is unlikely to create severe problems unless there are other malefic aspects on this placement too.
Moreover, Mars' aspect on the third house enhances an individual's communication skills and helps them express their thoughts more effectively. It can help develop leadership qualities by boosting self-confidence levels. In contrast, an aspect on the sixth house can increase an individual's enemies but will also give the courage to face them and fight back.
Mars is also aspecting the 11th house which pertains to financial gains, social circle and dreams/aspirations. Mars' influence on the 11th house can bring sudden financial gains or an increase in income to the individual. The natives are likely to encounter unexpected money flow as well as growth in their social circle because of fulfilling their aspirations.
Lastly, Mars' aspect on the second house brings significant changes in one's accumulated wealth, family life & speech. There may be fluctuations in one's financial status due to this Mars aspect. However, if there are positive planets like Jupiter present for support, it may help generate more income and overall benefit from business investments.
In conclusion, Mars placed in 8th House house for lagna Cancer indeed has a moderate influence on various aspects of life. This placement affects houses such as the fifth house (education/creativity), tenth house (profession/status), third/sixth houses (siblings/enemies), eleventh house(financial gains/social circle) and second house(wealth/family life/speech) but without causing any serious harm. The result depends not only on planetary positions but also on an individual's overall horoscope that includes other supportive planets aspects or exaltation/dignity position etc.